We use to grow a couple two or three hundred tomato plants per year and we never potted up. We sowed them in beds and never added any soil or anything - once they got big enough we pulled them up and transplanted them.

Mike

Carolyn, until you try it, you'll see that the non-transplanted seedlings are NOT set back at all.

Carolyn has done it both ways over the years as have many others here, myself included and we have posted many pics of the differences in root development, plant health, plant size, etc. Since this is done at the true leaf stage, transplant shock in these very young seedlings is minimal if any. Granted, non-transplanted ones never have transplant shock but then they don't have near the fibrous root development either, and that's what counts for the plant.

I doubt we'll convince you but for what it is worth, commercially sold transplants like those sold at nurseries and big box stores have all been transplanted a minimum of 2x and sometimes 3x.

Dave

I just recently bought a pack of 16oz dixie cups. I will put the tomatoes in these before planting them out/giving the extras away. I am starting my seeds on the 18th in plastic egg cartons, and I expect them to grow for a couple weeks before I put them in the cups.

Dave, I just repeated what Carolyn had said to me, word for word.

Carolyn said:
"Corrie, until you try it, you'll see that the transplanted seedlings are NOT set back that much"

Corrie said:
"Carolyn, until you try it, you'll see that the non-transplanted seedlings are NOT set back at all."

Dave said:
"I doubt we'll convince you"

I'm just discussing something.

Dave said:
"Granted, non-transplanted ones never have transplant shock but then they don't have near the fibrous root development either, and that's what counts for the plant. "

The paper that Carolyn linked says they do. Just like they develop another tap root later too.

Carolyn quoted:
"(It is clear that such plants ( ones with tap roots, CJM) could be set into the field only with difficulty. Hence the practice of transplanting one or more times before the plants are finally set into the field. Transplanting or potting of seedlings tends to modify the natural taproot system into a more or less fibrous one, due to the injury to the taproot. The change in the root system is really very profound (Fig. 70).)"

Carolyn said:
".... which is the summary rationale for transplanting to go from a tap root structure to a fibrous root structure/ "

I agree. Because you would have to grow seedlings in ridiculously deep pots in order for them to maintain the tap root they are referring to, and dig deeper holes to plant them. That makes setting them out in the field difficult.

They still go on to say that curved tap roots produce profuse branching roots.

Still looks to me like they are just saying that repotting up into shallower pots is better - for the farmer - than trying to grow them, as seedlings, in deep pots to maintain the tap root.

Looks to me like they are just comparing seedlings in deep pots to maintain the tap root, and seedlings repotted to damage the tap root and cause them to branch. Thus supply enough roots to support the plant when it is put out.

They didn't mention damaging the tap root from the get go by starting seedlings in shallow pots. Then forcing them to grow branching roots up the stem as you add dirt.
But the did imply it.
By stating that a curved tap root produces profuse branching roots at the curve of the tap root, or a little bit above it.
Which is exactly what would happen to a tap root when it only grows an inch and hits the bottom of a pot. Burying the stem would give it that little bit to grow branching roots above the curve that they referred to.

I don't grow seedlings the way some of you guys do with hundreds/thousands to a flat
that have to be repotted
and the way you do it works fine for you.

I don't have to repot, so my way works just fine for me.

and the link that Carolyn posted says it's the same thing.

Corrie

OK---what I took away from the article Carolyn linked to was that it actually vindicates Corrie's method. Although inducing a fibrous root system via transplanting the young seedlings was advantageous, growing them in pots---which has it's own mechanism for inducing a fibrous root system---actually provided a 17% greater yield. When finally planted out in the garden, the fibrous root system of the container grown plants suffered minimal transplant injury as a result of having been container grown---and not transplanted.

From the article:
=============================================

Transplanting.--Since the tomato plant is tender and cannot be grown in the field until danger of frost is passed, the crop is grown from plants started in greenhouses, hotbeds, or cold frames. The greatest yields and profits are obtained from well-grown, early set plants. 70, 5 The relation of the root system to transplanting is an important one.

Usually the seedlings are transplanted when they are about 2 inches high and more space given each. In this process the roots are more or less severely pruned and the new root system is much more fibrous. Frequently a second transplanting is made in which each plant is given still more room or transplanted in a suitable receptacle such as a flowerpot, paper band, tin can, etc.

Since the root system is disturbed and the development of the plant more or less checked at each transplanting, it might be concluded that plants grown from seed sown directly in pots or other containers would grow more vigorously and give a higher yield than those once or twice transplanted. In fact this has been shown by numerous investigations to be the case. That transplanting in itself does not promote an early crop nor an increased yield has been also clearly demonstrated. In an experiment in Wisconsin

three crops of tomatoes were grown . . . In each case seeds were planted singly in 6-inch pots in the greenhouse; when the plants were about 2 inches in height, two-thirds of the whole number were dug up and reset in the same pots; later, one-half of these were again transplanted in a similar manner. As soon as weather permitted, 10 plants of each lot were knocked from the pots and set 4 by 8 feet apart in open ground, every precaution being taken to avoid injury to the roots. 29

Those not transplanted yielded more than those once transplanted, while those twice transplanted yielded least. The total for 10 plants with each treatment during a 3-year period was, 1,175, 1,131, and 1,001 pounds, respectively.
==============================================

Of course, I could be interpreting this wrong ;-)

~~~ Those not transplanted yielded more than those once transplanted, while those twice transplanted yielded least. The total for 10 plants with each treatment during a 3-year period was, 1,175, 1,131, and 1,001 pounds, respectively. ~~~

No, I don't think you are interpreting this wrong but some perspective and practicality is in order.

As I recall, Carolyn has repeatedly said that she potted up once into nursery flats and I personally recall her cautioning against more than that unless necessary.

In the report, those not transplanted had an increased yield over those transplanted once of just 3.9%. Hardly earth shattering.

Given that most of us don't have greenhouses and must use indoor lighting to grow starts and said lighting needs to be fairly close else excesive leggyness results, and that the shadows from taller cups or pots would exacerbate the leggyness and perhaps increase damping off, it seems a fair trade.

Add to that, increased seed usage, vastly increased space and therefore lighting appliances and electricity requirements.

The cost in production is less meaningfull than each truss giving you 11 equally sized tomatoes instead of twelve or as the test showed 1.5 lbs/plant

dave, are you saying that you would rather take the extra time and do the extra work to pot up even though the article that Carolyn referenced indicated that this would result in less production? Any why exactly would no potting up require increased resources -- sure my seeding pots don't require a lot of space, but once I pot up once or twice to larger pots, what is the difference in the space that I would use at that stage and the space that I would have used if I started with the same number of same sized pots with no plans to pot up?

~~~ but once I pot up once or twice to larger pots, what is the difference in the space that I would use at that stage and the space that I would have used if I started with the same number of same sized pots with no plans to pot up? ~~~

The flats I showed in the pic further up the thread, still fit under my lights but barely. Bout the time they were getting crowded, temps had eased enough to potup again and move some to a ho-made temporary mini greenhouse to be held in reserve as spares should they be needed. Think I used ten or so.

So, I'm considering sowing in the flats shown to cut out one step but I do start other veggies inside too so maybe not. I'm not really anxcious to give up more room and double my lighting and even if I were, it wouldn't address the other problem issues mentioned in the previous post nor that we are only talking about the equivalent on avg of one good tomato from much bounty.

I tend to agree that the article disagrees with Carolyn.
However, the article is 82 years old,it is not necessarily
the "bible" on the subject and Carolyn and Dave may have run even more extensive tests than the author(who was probably not a tomato nut.)
Since I have other gardening addictions to occupy my time I don't transplant and was delighted the article seemed to give me the thumbs up.
Wisdom is in the eye of the beholder.
Larry

I think in reality the clear picture here is do what you like to do, and if it has shown success then continue doing it. I actually enjoy the potting up process. It's a right of spring! I call my gardening buddy Pat and say 'It's time to pot up! Get your butt over here!' lol> After a long winter it's nice to get the plants out from under the lights and into their 4" pots and in the greenhouse for the last few weeks before putting them into the ground.

I pot up, but ya know what? I don't do a conventional 'hardening off' although many say it is a necessity. I've never had a problem, but there are probably 10 people to my 1 who say it is a 'must'. I keep the door and window open in the GH and their might be an occasional breeze, but I don't move them in and out of the sun/wind etc. That to me is too much work LOL. So to each their own. Do what works for you. I really don't see the point of too much arguing on the subject. It seems there are some stubborn folks on both sides of the issue.

Duane

"three crops of tomatoes were grown . . . In each case seeds were planted singly in 6-inch pots in the greenhouse; when the plants were about 2 inches in height, two-thirds of the whole number were dug up and reset in the same pots; later, one-half of these were again transplanted in a similar manner. As soon as weather permitted, 10 plants of each lot were knocked from the pots and set 4 by 8 feet apart in open ground, every precaution being taken to avoid injury to the roots. 29

Those not transplanted yielded more than those once transplanted, while those twice transplanted yielded least. The total for 10 plants with each treatment during a 3-year period was, 1,175, 1,131, and 1,001 pounds, respectively."

When the seeds are STARTED in a 6" pot and not mucked with they did better than seeds planted in same pot and merely removed and put back...this is different than planting up, which benefits seedlings started in the tiny cells most of us start them in...

"That early production is influenced by reducing root injury in transplanting is shown by the following experiment. Seeds of the Bonney Best variety were sown in the greenhouse. Seven days later some seedlings were transplanted 3 by 4, inches in a greenhouse bench. Others were set 2 by 2 inches in flats. Approximately a month later the flats were thinned by removing alternate plants. The plants thus removed were set in 4-inch pots. Another lot of seed was sown a week after the first transplanting. These seedlings were not transplanted. All four lots were set into the field on May 12, 4 by 4 feet apart. The potted plants, which were no larger than the plants in the flats but had a better root system, grew much faster than the others. They came into bearing early in the season when the price was high and gave by far the greatest financial returns, although the plants from the greenhouse bench and flats gave practically the same total yields. 70

Some of the most successful northern growers complete the indoor growth of the plants in 6-inch clay pots such as are used by florists. By keeping the plants cool and well ventilated toward the last of their indoor period they become very strong and stocky, having a wonderful root system. 8"

In this case, the ones transplanted to 4" pots did much better than ones transplanted to smaller pots AND the seedlings that were not transplanted at all...

So the conclusion seems to be that if you plant in larger pots to begin with you'd do best by not transplanting up but if you grow in small cells the reverse is the case...

That said, it seems by placing more soil around the seedling as it grows seems to be a way of transplanting up without removing the plant from its container...my only concern with this method is not being able to get the light source close enough to the tops of the seedlings...

This topic pops up from time to time and is always confusing because it adresses/confuses two practices, direct seeding into the garden, and benefits of multiple up-potting. I think commercial growers used to (still?) do seed sprouting flats and then spacing flats (small cells) and then additional spacing flats (larger cells)before planting out. It is described this way (in part)in "Its a long road to a Tomato" by Keith Stewart. Why it was/is done this way probably had more to do with economy of dynamic space in the greenhouse than end result in the field, but you know how logic progesses..."My Daddy did it that way and said it was better for the plants so I do it that way."

Way back when, I went through the above mentiond article with a fine toothed comb to see exactly what they were saying, and I just went through it again. This is what they are saying. 1) Do not direct seed into the garden. 2) It is not better to repeatedly pot up seedlings. Seeding into a large pot is best.

Two topics here

Topic 1. Direct seeding into the garden (no transplants) vs growing in a pot first. Growing in a pot is better because of the fibrous root system caused by transplant root damage or tap root inhibition.

"Fig. 71.--Three tomato plants from seed of the Baltimore variety planted at the same time. The one on the right was transplanted to rich soil in a 4-inch clay pot when it was about the size of the plant on the left. The center plant, with spray material on the leaves, was transplanted to soil in a cold frame. The plant on the left was not removed from the original seed bed. Note the comparative root systems. The tomato on the right is a desirable plant for setting into the field. (After Brown, Purdue, Ind., Agr. Exp. Sta., Bull. 288.)"

and from the paragraph above

"Transplanting or potting of seedlings tends to modify the natural taproot system into a more or less fibrous one, due to the injury to the taproot. The change in the root system is really very profound (Fig. 70)."

Note 'or potting'

Topic 2.

Number of transplants before setting out.

"Usually the seedlings are transplanted when they are about 2 inches high and more space given each. In this process the roots are more or less severely pruned and the new root system is much more fibrous. Frequently a second transplanting is made in which each plant is given still more room or transplanted in a suitable receptacle such as a flowerpot, paper band, tin can, etc.

Since the root system is disturbed and the development of the plant more or less checked at each transplanting, it might be concluded that plants grown from seed sown directly in pots or other containers would grow more vigorously and give a higher yield than those once or twice transplanted. In fact this has been shown by numerous investigations to be the case. That transplanting in itself does not promote an early crop nor an increased yield has been also clearly demonstrated." Then they give the production numbers.

Conclusion
Yes, it is fine (best?) to seed directly into large pots... And, multiple transplanting is not beneficial. To save space, most of us sprout multiple seedlings and then translant most or all of them them into additional pots (once). Anything more is a waste of time.

Those of you concerned about shading affect of large pots...I use clear 32oz deli containers (4.5" wide). Seedlings go in at first leaf stage almost to the bottom and potting mix is repeatedly added as the plant grows taller. This way I do not have to trim bottom leaves and bury the stem in the garden because I already have 5 inches of rooted stem in the pot. Does it matter for a home gardener? Probably not, runt seedlings generally catch up to "super pot" seedlings and I get more tomatoes than I can use no matter what.

I've done it several ways and will continue to do so as I've been keeping records and doing some experiments. So far my direct sown with either plastic buckets with plastic over the top or WOW's to get germination sooner and the ones that I have transplanted and never potted up have done as well if not better than the ones where I potted them up. When you pull them in the fall you will see a noticebable difference in the roots. I had noticed volunteers although later always seemed to do very well. After talking to local horticulturists and extension personnel and other market growers in this area decided to experiment for myself. And like one stated here where it is so hot unless you mulch heavy he feels the roots that go deeper are more beneficial. I will say in a terrible year last year that I had five of the direct sown plants and a total of 88 plants and four of these five were in my top six yield wise and did better than their counterparts that was potted up. What does this prove? Not much except that I can't see a enough difference to justify the time and expense of potting up. You can start in a cup and add soil like one mentioned. It is like so many other things find what works for you and do it. More than one way to skin a cat and in this case I'm not sure any is better. JMO

Do what works for you and let someone else do what works for them. If you are new to this maybe try a few one way and a few others the other way. See how it goes.

dave, I understand issue with having enough room (since your final is in the greenhouse...I use my window space for fresh seedlings/1st potup/final potup, so space issue would not affect me), but what 'other problem issues mentioned' are a particular concern to you? If you are talking about the difficulty of setting out with a taproot, I thought that was covered above.

Larry yes the article is old, but I doubt that tomato growth, rooting, and fruiting characteristics have changed much in that time (though the particular weather/precipitation conditions in that season may have influenced the results, maybe one root structure was better suited to the conditions than other root structures, maybe the soil was particularly deep and well adapted to accomodate a tap root, who knows). I am planning to experiment a bit this year, but with only 40 plants my results won't have a lot of validity. However, it does seem to me that the vast majority of advice and opinions provided on this site are based on experience or observation, and with the exception of issues related to genetics or other similar mathematically determinable topics, when push comes to shove there does not seem to be a lot of empirical supporting information provided.

Duane why would you do something if it took more work and looks like it may decrease production? Re. hardening off I also never hardened off and had never had an issue until 2008, when plants were quit affected by sunburn (even though weather was no different than in 2005/6/7), the only big difference I saw in the seedlings was the poor root structure in 2008 when set out, maybe that affected their hardiness and ability to deal with the environment, who knows. Hopefully my experiments will give me lots of extra seedlings this year, I can set some out without hardening and see what they do.

Funny thing. I was liking the start in 1 inch of soil and add along the way. I'd have to careful and it might be messy and it might be multiple times...
LOL Now doing one transplant seems easier.
Larry

rotfl at Larry

Larry, I only do it one time.
But, like I said, I still have to transplant - pot up - some of them because I plant more than one seed in a 4 inch pot.

Right now, the ones that I did not have to transplant, are ready to go out.

The ones that I did have to transplant are smaller, and are a good week or two away from going out.

Hey tank, you asked for opinions, and boy did you get them.
LOL

Corrie

Anthony,

I've never had damping off problems but I've always potted up and other than for watering in a transplant, bottom watered and used an oscilating fan.

The taller cups "could" make damping off more likely, would mean the plants are further from the light (for a while) and I don't really see it as less work to have to be so careful in staging up the soil around such flimsy plants.

I'm thinking about how to avoid the second pot up but my starts look good and in general I'm happy with production.

""The taller cups "could" make damping off more likely, would mean the plants are further from the light (for a while) and I don't really see it as less work to have to be "so careful" in staging up the soil around such flimsy plants. ""

"So careful" in ripping them out of their pots, ripping their roots apart, trying to handle them without breaking or crushing them, and fumbling around with putting the same amount of soil back around them (exactly like you would do with just adding soil to the pot) and burying them again.

LOL Dave I'm just jerking your chain here because it sounds like you are grasping for straws.

Adding soil is exactly the same as adding soil when you transplant them.
Only you leave out about 1/2 of the work and don't have to actually handle the seedling.

To repeat myself again and again, I have to do it both ways.
Not having to un-pot and re-pot is a lot quicker. At least it is for me.

AND my plants - your mileage my vary - grow a lot faster when I don't have to handle them so much, don't have to set them back by transplanting and re-potting them.

Corrie

Dave like one/some others mentioned I really do enjoy potting up because I like to get my hands in the dirt while the snow is on the ground, but other than that I would rather not have to do the work. Given the angle that the sun comes in the windows, I suspect that except for a few prime sunny spots, the sun will not hit my seedlings if they are in 8-inch pots. I will test out maybe 10 plants like this, see how it works. I also probably get more production than I need, with the exception of last year, so does not make too much difference, except for the extra work involved (and as you say there would be work in maintaining the setup with larger pots and with topping up soil as the plants grew).

Ideally I would like each individual plant to grow more fruit. This would allow me to start fewer plants, which would allow me to give seedlings more attention if needed (and take up less space), and allow plants to be spaced farther apart in the garden. Even 40 plants is too many for my garden, 26 would probably be ideal, in allowing 4 feet between plants/rows. I do want about 10 to 15 varieties, but with 1 or 2 plants of each particular variety, it would be disappointing if 1 or 2 of those 1 or 2 failed...so bumping up to 40 plants allows 2 or 3 of each (instead of 1 or 2), but spaced closer, less production, less ideal conditions, etc. In the first year I did brandy sudduth, one plant had 3 good fruits, another had a few good ones and several small ones that never really ripened, but the best plant had probably 20 fruits in huge bunches that averaged 1 pound per fruit. If I had only grown the first two plants I might have not grown the variety again (as some others seem to have decided on the "what will you NOT plant this year" thread). If something I did influenced how well or poorly each of those plants performed, I would like to know it. I would have expected that the agricultural industry would have done the work to provide us with the answers that we need, but there does not seem to be much agreement here on what should be done, or at least does not seem to be much in the way of supporting evidence besides 'this is what works for me and what I have always done'. If we do things because they work well enough for us and do the trick, maybe that is a reason to not put too much work into improving things, I can accept that. However I still would like to find a way to reduce # of plants to allow better spacing/more attention (if required) per plant, and maximize production on each of those plants. Fewer plants and same production would be ideal, I am sure there is plenty of room for improvement in my garden.

Corrie, I'm hardly grasping at straws and you see what little stress shows on my plants.

Speaking of grasping, just how do you remove the excess sprouts from the bottom of your tall pots? My fat fingers would definately do more harm than good there. Maybe you put more stress on them than I do since I can pop em out and work on em where I can see what I'm doing.

I'll grant you that this discussion has encouraged me to think about the issue more deeply than I have previously but only for the second transplanting.

P.S. Even Charles Wilber potted up once at second true leaf stage. pg.42-43

AND my plants - your mileage my vary - grow a lot faster when I don't have to handle them so much, don't have to set them back by transplanting and re-potting them.

Corrie this is something that I have also seen, but my question is whether top growth is lagging because the plant is growing more roots instead...and if so whether that makes a better plant in the long run. Maybe this makes a more fibrous root structure (I think it probably does, seems to be agreement here that this is the case), but does this lead to increased fruit production or not? If not, then why would I care if the root structure was more fibrous?

Anthony, a plant needs roots to support the top.
If the tops not growing, then either it doesn't have enough roots, the roots are damaged, etc.
A plant's not going to grow more roots than the top will support either.
Either way, the tops and roots will have to balance.
The paper Carolyn linked says they are going to do what they are going to do, and end up with enough fiberous roots in the end anyway. The plants even regenerate a tap root anyway.

Sheesh, Dave now you are attacking my "tall pots"..LOL

Even though I do them exactly the way you do flats, that was not the discussion.
The discussion was 'not' having to do it. rotfl

grasp grasp grasp

Corrie

However, the article is 82 years old,it is not necessarily
the "bible" on the subject and Carolyn and Dave may have run even more extensive tests than the author(who was probably not a tomato nut.)

***

Yes, I pointed out that the article was from 1927 and I also pointed out that the methods used back then are not necessarily the ones most of us use now.

At this point I'm almost sorry I posted that link, LOL, but I've done it before at several sites and it has provoked discussion and consideration and introduced the topic of tap root vs fibrous rooted plants, and that's good as I see it.

So do whatever you want to and always try more than one method and always use controls is the way I see it when trying new ways of doing anything. ( smile)

Carolyn, who has tried many methods, some based on what commercial farmers use, most based on curiousity and sheer experimentation on her part.

I start my seeds in an unheated garage because my wife doesn't want several trays of seedlings in the house. The garage stays warm enough for the seedlings, but is a little cool to start seeds. That is why I use a heat mat. If I was to start seeds in larger containers to skip the pot up step, I would need 8 heat mats. Now, I just don't have the money for that. So the advantage for me is that I can start the seeds in 72 count flats on a heat mat and then pot up to 16 oz cups when they get their true leaves and no longer require the extra heat. (I made the mistake of trying some in 10 oz cups last year to save room on the extras I was going to give away, and they got crowded, fought for the light and got leggy, so I will use only 16 oz from now on.) That is where they stay until they go outside to their final home. If you have the room to start in larger containers then do so. After all you will be essentially "potting up" when they go to the garden. But I choose to do another way. To each their own. I do this for the hobby. I enjoy it. You should to. Whatever you enjoy doing and if you get the results that you are hoping for, then it is the right way for you even if others see it differently.

jj

Thank you everyone who shared their experience. This forum is so important for those of us who want to learn. My conclusion is that if everything else goes fine, either method might be fine for me. I'm going to do half using Corrie's method and the other half I will pot up.

Who transplants seeds in the wild? Isn't all this transplanting nonsense just so you can get a headstart on your neighbor and a lot of profit to those who market transplanting goodies,like seed starting mix and peat/cow manure pots.

Hi weetoots,
I grow 600 determinate tomatoes in the tropics & there is no reliable seedling survival with open field sowing because of the day time heat.
Of course the mainland growers have my sympathies because I never need more than some shade, water & monitoring to sprout tomato seeds.
Potting up is best for me because of basic materials scarcity.
Sometimes I use perforated styrofoam cups, which are easier to shift around than black grow bags when dodging sun rays & culling duds.
Usually I've got to sow in a few plastic basin tubs that necessitates pricking out seedlings too. These are also easier to pot up into cups than bags.
Main reason I like potting up is to let seedlings get big enough to set out in the sun. Otherwise in the shade they just get too leggy.
Gives me a chance to observe which plants are robust & select those for planting. This allows my back-up choices to hang around because with 600 set out into the field I always have some that get botched.
I toughen them up first by progressive exposure time to direct sunlight, otherwise have minimal survival or stunned plants that don't take off.
Might as well mention that I like to plant out horizontally, a.k.a. trenching, because have both limited irrigation water & typical washed out tropical soil.

I don't see how potting up decreases production. You can show me study after study and I just don't buy it. Hey, I can be stubborn too! Besides, I start my seeds in 36 cell trays, and in some case 72 cell trays. When I give plants away which I do every spring they have to be in 'something'. I'm not going to scoop them out of a one inch cell and hand somebody a plant with the roots dangling????!!! So I pot them up. Sue me! LOL>

As I mentioned before I ENJOY POTTING UP! To me it is not more work. It is FUN! Knowledge and different ideas are great, but c'mon folks, there is no 1 right way, and 1 wrong way to do most anything. Lighten up. Have fun, enjoy your hobbies and don't sweat the small stuff.

Duane

Like virtually all issues discussed on this website that do not simply come down to a matter of mathematics, seems like nobody can provide an answer on this issue. I wonder how many millions or billions of hours have been put into the growing of tomatoes in north america, you would think that someone would have some empirical bases for why we should do/avoid doing certain things.

you would think that someone would have some empirical bases for why we should do/avoid doing certain things.

Aww Anthony, we do, you know that. ;) Problem is no matter how much evidence there is, not everybody is going to buy into it. Given human nature, just too many other variables come into play.

This issue is a good example - it's been discussed here ad infinitum over the years with comparative photos and notes up the wazoo. Carolyn, who has grown more tomatoes than all the rest of us put together, offered her input once again. But in spite of all that there will always be some folks who for their own reasons just don't buy it. And, truth be told, if they are only growing a few plants from seed, that's fine. If they are growing 50+ like many of us it is a different story.

Which brings us, as per usual, to try it both ways and see which works best for you. Been there and done that. And with no loss - indeed increased production, healthier plants, bigger seedlings with uniform node spacing and length, sturdier stems, increased pest and disease resistant plants, less watering needs, more drought tolerant plants, etc., etc.

But to each his own. ;)

Dave

washes the windows, does the laundry, and tutors the kids in molecular physics..........

.

But Dave the link that was posted seems to indicate that the opposite is the case. So, we are left with some evidence saying one thing, and people's postings saying that according to their experience another thing is the case...often ending with 'to each his own', which is something that is at the end of many posts by the resident experts whenever they are questions on the basis for their contentions. My contention is that this type of thing is really not much use, except to indicate that they should try a variety of things and see what works best. I don't need any expert opinions to be able to try different things and see what works; I need expert opinions to tell me what will work and why it will work and back it up with empirical evidence (while also indicating where different underlying environmental conditions will positively/negatively influence the results) so that I can avoid trying things that probably will not work. For example, if a particular tomato needs a long season and hot dry weather to perform, I will conclude that it probably will not work well in my climate. That is an easy one. The rooting/potting up/production issue is probably more complicated, and as I said who knows if the particular weather in the particular season in which the authors of the referenced article performed their experiment influenced their results, but nonetheless their results indicated that plants that were potted up once produced less fruit than plants that were not potted up, and plants that were potted up twice produced less fruit than plants that were potted up once. Who cares about what the root structure did if that root structure did not lead to more productions. When I grow plants, it is so that I can produce fruit, not so that I can have nice looking roots.

I see this as similar reasoning to the discussion of when to start seeds/seedling size at set out (FORGIVE ME if my recollection gets some facts confused regarding what people said, I may be mixing it up with other similar discussions). The expert opinion was against starting seeds more than 6 to 8 weeks before set out and would have preferred to plant seedings that were no more than one foot tall, with submissions that allowing seedlings to grow to 2 or 3 (or 4) feet tall before set out would cause developmental problems at certain stages of growth and result in a plant that was basically less healthy overall. In my garden, larger/older seedlings produce more fruit by the end of the season that younger/smaller seedlings, but at best this seemed to have only reluctuant acceptance, and again I believe we were left with 'to each his own' from the experts. As with rooting systems, I really don't care if particular developmental stages of the growth of my plants is negatively impacted, if the only way to avoid such an impact also results is lower production. Makes no sense to me.

So why should I want more fibrous roots? Will roots be shocked into increasing their growth if I pot up, and what will be the result? If the end result is not more tomatoes, why would I want to do this? Why should I set out 6 to 8 week old transplants that should be approx. 1 foot tall (*besides the HUGE convenience of both, which I agree is clearly the case)? What stages of development will be negatively effected if my set out seedlings are 10-12 weeks old and 3 feet tall? If the end result is not more tomatoes, why would I want to do this?

I am not trying to be a jerk and I am certainly not suggesting that the experts are wrong, I just want to know why they are right and know that what they are suggesting will result in increased production...based on empirical evidence, if it exists.

But Dave the link that was posted seems to indicate that the opposite is the case.

No, Anthony other folks interpretations aside, the article linked in this current discussion indicated that a potential 3% production decrease occurred which could or could not be due to other environmental factors. 3% is nothing in any one study. A margin of error of at least 5% is normally accepted as due to variables beyond the study's control and my years of experience shows that an actual increase in production occurs simply because healthier plants produce more. But some ignore all the rest and find that 3% to be justification for their views.

Have other studies been done? Yes. U of Mississippi Extension and U of CA Davis for 2 that I know of off hand but others have also been linked in the past discussions and are available if one want to browse through all those other discussions. Local extension offices (you have the equivalent) are a wealth of info, studies, etc.

Sure we often add "try it and see which works for you" because one can get awfully tired of all the nitpicking that happens when their experienced opinion is offered - especially so when it has been given time and time again and nitpicked time and time again. It's clear that not only do they not want to review past discussions but don't want to change the way they do things. Fine. It is just a waste of time to try to convince someone who doesn't want to learn so you can only hope they will give both approaches a try.

Why should you want fibrous roots? For better and more uniform moisture and nutrient transportation.

What does that get you? Stronger, healthier plants and healthier plants better tolerate transplanting and early season stresses.

What can it lead to? All other factors being equal, maybe less BER, possibly greater disease resistance, maybe earlier production, perhaps longer production, etc.

But no one except you can control all the factors in YOUR garden. We don't know your soil conditions, your weather conditions, your feeding/watering regiem, your soil pH, etc. But we do know for a fact that (1) commercial growers do it routinely and have for eons, (2) commercial greenhouses do it routinely and have for eons, and (3) that in our gardens, staged transplanting works exceptionally well and does NOT result in a decreased production. Extremely clear and convincing to me, but you have to decide what that info is worth to you.

Now will they develop fibrous roots eventually on their own? Sure, eventually about 2 weeks after transplanted to the garden. Want to wait? You have a short growing season. What else is happening to the plant while you are waiting? Will they develop to the same degree? No, simply not possible in garden soil vs. soil-less mix. Several of us have posted pictures in the past showing the differences. Will they develop faster if you pot up? Definitely.

If you have some extra seeds and a bit of spare time, there is an easy way to test this if you wish and while I won't post it here and open myself to even more ridicule like the post above yours I will send you the details if interested. Just email me. ;)

Dave

Dave thanks for the response. I definitely have extra seeds and some spare time, and I am anxious to experiment to see what plants/roots do while seedlings/during potting up, and (to a lesser degree, unfortunately, due to limited space) I am also anxious to see what plants do once they are in the ground.

I also have several willing potential beneficiaries of stray and extra plants, regardless of age/size/roots, so the extra seeds wont be wasted. I had planned to do some informal tests and would like to do so as intelligently as possible so would like to hear what you suggest...but I am not sure where to get your e-mail.

I also agree with much of what you say and understand about huge potential differences in gardens/climates/growing seasons/etc., and understand why you would not want to make the effort to counter everyone's nick-picking questions in response to your advice...but they result is that our nit-picking questions are not answered! I have an ok idea of what seems to work in my garden, but still need more info...and that info is proving hard to find...and experiments will take too many years to yield results. I am not patient.

Also re. the linked article, it was not the 3 percent decrease in production for 1 pot-up that caught my eye (because of the reasons that you posted), but I believe the difference was 17% when two pot-ups were involved, which all other things being equal seemed to raise the possibility that the results of the experiment were significant and perhaps valid.

Just click on 'My Page' link after my name for email.

got it, thanks d...missed the 'send me an e-mail' link.
a

"while I won't post it here and open myself to even more ridicule like the post above yours "

Good Lord
You twist every thing I say
then claim you're the victim.

Dave, you and Carolyn both jumped in my drawers for just questioning a scientific article that Carolyn posted

Supposedly that article was to back up what you and Carolyn were saying.

Since the scientific article states the complete total opposite of what you are saying
I tried to discuss it with you to see if I'm reading it right.

Next time don't even bring it up if you want to run and not discuss it.
and don't dish it out if you can't take it.

That article is about 80 years old.
Has anything new come out to change it.

or has it stood the test of time

Corrie

Dave says:
Carolyn, who has grown more tomatoes than all the rest of us put together.

Wait now that's getting a little carried away isn't it??

OK Corrie,

Zone 11 is the warmest of all the Zones in the continental US with an avg annual minimum temp of above 40F. Its not surprising_that you_ can do things in early season with your plants that almost all of the rest of the country cannot. Most have to worry about frost dates, methods to extend their seasons, interior space dedicated to early sprouting and all the paraphanalia that goes with it, you dont.

IÂm sure that you have your own weather challenges, shade cloth is perhaps a good idea for you? It would hurt my plants, definitely reduce production. See what IÂm getting at? Trying to give each of mine a four inch pot from the start would mean several times the space, fixtures and electricity to run them. I donÂt have the luxury of your solar arc or soil temps and most others donÂt either.

"I start seeds out with about 1 inch of potting soil in the bottom of a 4 inch nursery pot. In the sun. As the sprouts get taller, I just add more potting soil to the pots until it's at the top. By the time I'm ready to put them out, they are 5-8 inches tall."

"I'm only giving them about 3/4 inch of potting soil to grow any kind of tap root. That's damage to the tap root right there. And I don't have any lag time while they stop to regroup from transplanting shock. "

"The ones that I leave alone and only add more potting soil, out grown the ones I replant 2 to 1."

This is simple enough to test.

"If I could work a picture on this thing,"

I can.

I'll test it, fairly but it will be limited to just a few. The space thing ya know.

Corrie - no one "jumped your drawers" whatever that means, but if indeed the article said just the opposite of what we were saying, as you claim, then Carolyn obviously wouldn't have posted it as supporting evidence now would she? So, clearly the alternative interpretation of the article were less than correct. Not to mention that most find the extensive pictures in the article quite enlightening and "proof of the pudding" so to speak, even if they don't grasp all the data.

And since the study has since been replicated using modern techniques in other studies, both formal and informal and mentioned above, yes, it has stood the test of time.

If you care to join the International Society for Horticultural Science you can read some of those studies - specifically REVIEW OF TRANSITIONAL DEVELOPMENT OF PROCESSING TOMATO TRANSPLANT PRODUCTION but it cannot be linked or copied here.

But the point is they are not readily available to the general public (the Mississippi and U CA Davis studies are but I don't have the links handy tho have posted them in some of the many previous discussions on this). Simply Google 'tomato staged-transplant root development' and then click on Scholar Articles link. (Unfortunately, this discussion has now moved up to #3 on the search page list.)

Or you'll have to take the word of experts on them and if Dr. Carolyn Male, a noted authority and author on tomato growing advocates it then at the very least it should be given due consideration rather than just tossed off as "splitting hairs".

Also, please keep in mind that there is more than one Dave participating in this discussion (which I swore I would ignore and then didn't) so please don't credit me with all the differences of opinion.

Dave

DLD - you likely know as well as I do how many tomato plants Carolyn has grown, directly or indirectly, over the years. It's well into 5 digits last I heard. So there may a little bit of literary license in that statement, but it ain't much. ;)

Holy Pandora's box Batman!
When this tread started out I posted "Do what matters most to you and don't mind that what matters to others..to each his own..
seems some people have their own opinion that don't agree with others..
They (we) are called subjective critics...
Do what works best for you..

I'm noticing some wording in the controversial article that may explain the results-

"Usually the seedlings are transplanted when they are about 2 inches high and more space given each. In this process the roots are MORE OR LESS SEVERELY PRUNED and the new root system is much more fibrous. Frequently a second transplanting is made in which each plant is given still more room or transplanted in a suitable receptacle such as a flowerpot, paper band, tin can, etc.

Since the root system is DISTURBED and the development of the plant MORE OR LESS CHECKED at each transplanting, it might be concluded that plants grown from seed sown directly in pots or other containers would grow more vigorously and give a higher yield than those once or twice transplanted. In fact this has been shown by numerous investigations to be the case. That transplanting in itself does not promote an early crop nor an increased yield has been also clearly demonstrated. In an experiment in Wisconsin..."

When I transplant 2-3" seedlings, 1-4 to a peat pellet, I pull off the netting and VERY CAREFULLY with the care of a brain surgeon (McDreamy would be proud) separate seedlings so as to interfere with the root system as little as possible. If the roots were severely pruned I can understand the plants being set back.

Earl??? or someone??? once posted about hole preparation, taking the size and amendments added to extraordinary lengths. The resulting monster plants had incredible yields. I don't make it to that stirling example but I would think that might make more difference that some piddling early seedling handling. My grand experiment this year will be adding Glacial Rock Dust to my planting holes.

I think it's important to consider any poster's location and conditions, as I couldn't apply either the Florida or Wisconsin results to growing in my cool and late growing conditions. My experience has been that some of my seedlings grown under lights all in the same conditions will make it to the lights and be candidates for planting out after 6-8 weeks, other varieties or individuals planted at exactly the same time may take 10-12 weeks to attain the same size and get set out. This is fine with me as it staggers my work load.

The scientifically inclined person will do the experiments necessary to find out the best procedures for their conditions. It's nice to have the expert opinions for a guide. As Carolyn kindly points out most commercial outfits do the transplanting and they take the time to find out what works. I used to take an easy approach and keep the seedlings cramped in their peat pellets until planting out but get much better results, earlier fruit, better yields, by transplanting once into 2.25" rose pots that fit great 36 to a flat, and then outside. The roots are very minimally disturbed. I plant deeply up to the bottom leaves every time. Tomatoes are marvelous the way the stem is all set up with those little bumps ready to make new roots. If I break off a seedling when setting outside, I just stick the top in a glass of water in the window and in just a few days can repot it and have it grow almost as good as new. Even then I don't see wilting, usually not much set back. Great plants. No wonder I can't resist them.:-P

Nancy

Oh good Lord again.

Read what I said:

Corrie said over and over:
"tank, I don't pot up either. I used to, but didn't notice a difference. "
"I have grown them side by side for many years, some disturbed and repotted and some not.
I plant several seed in one 4inch pot. Sometimes only one will sprout, sometimes too many and I have to repot them."
"I don't have to repot, so my way works just fine for me."
"But, like I said, I still have to transplant - pot up - some of them because I plant more than one seed in a 4 inch pot. "

And being in zone 11 has nothing to do with it.
Because I'm am not advocating any way of doing it,
and I am not trying to push one way over another.
I'm trying to discuss what that scientific article says.

Dave said:
"but if indeed the article said just the opposite of what we were saying, as you claim,"

Well, that's exactly what it does.
The article clearly says that plants that are potted up are "checked" with each potting, and the more they are potted up, the less they yield.

It says that tomatoes will form fiberous roots in a pot, without being potted up,
and it says that tomatoes can just form another tap root anyway.

It also says that damaging the tap root makes it convenient for commercial farmers to plant out the transplants, and that is why the practice is used.

Not because it makes the plant better,
Not because it makes the plant produce more fruit,
but only because it makes it more convenient for the commercial grower.

It also says those results were replicated many times in other experiments.

Sorry guys, you are the ones that turned this personal.
I did not.
I was discussing the article only.

Dave said:
"And since the study has since been replicated using modern techniques in other studies, both formal and informal and mentioned above, yes, it has stood the test of time."

Then Dave, it says the complete opposite of what you guys want it to say.

Corrie

Root damage is at the microscopic level. Root hairs, which are responsible for water and nutrient uptake, grow into microscopic spaces between soil grains. When you remove a plant from the soil, no matter how little damage you do to the larger roots, new root hairs have to regrow into their new environment. This is a setback in terms of efficient nutrient flow to the seedling, and thus growth. You may not notice it, especially if you are expecting something drastic to happen, but if you did controlled studies/measurements of hundreds of seedlings there would be a statistically significant difference in growth. It may only be a day or two difference in size, something that would not show up in my seedlings because of overall variability among seedlings and varieties, not to mention problems caused by uneven watering and fertilizing. Under some commercial conditions a day or two difference in growth could mean money (electricity for the greenhouse, water, nutrients...?). This discussion is analogous to the difference between what an artisan hand craftsman would do vs what a factory would do to save a couple of pennies on each part along the assebly line. Wasn't it Rockefeller who insisted that each oil barrel be made with a specific number of drops of solder, which ended up saving his company a ton of money?

Killing off root hairs can be beneficial. I recall one site recommending wilting the plants while hardening off. Many root hairs die in the dry soil, stimulating new growth/root branching. That's a bit too "on the edge of disaster" for me though.

Or you'll have to take the word of experts on them and if Dr. Carolyn Male, a noted authority and author on tomato growing advocates it then at the very least it should be given due consideration rather than just tossed off as "splitting hairs".

Wow, does she pay you to blow her horn in every thread here?

DLD - you likely know as well as I do how many tomato plants Carolyn has grown, directly or indirectly, over the years. It's well into 5 digits last I heard. So there may a little bit of literary license in that statement, but it ain't much. ;)

You embelish????? Naw!

OK, lets be clear, Carloyn is by no means an "expert" on tomatoes. Her expertise is limited to heirloom lore, what I would call ethnobotanical relationships and nomenclature, but certainly not horticulutral aspects.

JT, dude, take a chill pill man. That is a little rough on Carolyn. I think as much as anyone here, she has grown a few tomatoes over the years and can be considered to have a valid opinion. Expertise is a slippery trout of a term anyways. Any of us who has grown tomatoes for a decade or more can be considered experts (smile).

Noting the divergent opinions from so many learned experts
leads me to a couple conclusions:

1. The differences in plant performance between the
   potting up versus not potting up systems must be very slight; and then it is likely many other variables are controlling.
2. Indeed, the tomato seed is a hardy critter, likely to survive and prosper even when exposed to extreme differences in husbandry!

Well, I have been far too busy to do any real experiments, and I ended up starting my seeds a few weeks later than I had intended (seeds planted 8 p.m. on March 25, about 8 weeks before the below pics were taken). Planted seeds in trays of 2x2 inch cells. When a few sets of leaves had appeared and seedlings were 5 to 6 inches tall, I carefully removed them and planted in 10-inch and 8-inch round pots. Filled halfway with soilless mix, and when plants had grown tall enough I filled pots all the way. Used moisture control mix so only had to water once every 6 or 7 days. Applied 10-52-10 fert to aid in root growth (after last year's root fiascos) 3 times in 8 weeks. My plants at 8 weeks are 2 to 4 feet tall. Some have become a bit leggy recently. Overall they are far larger than plants that were 3 or 4 weeks older in prior years. Plants that I repotted from the seeding cells later than these are far smaller now. Plants that I repotted to pots that were smaller than 8 or 10 inch pots are far smaller now. All plants are the same age. Less potting up this year, less work, much larger seedlings at a younger age. Size of pot is quite clearly extremely important in determining seedling growth (proven in prior years and proven once again). Whether root develpment has been detrimetally affected by failing to leave the seedlings in a small pot and letting them become rootbound in an effort to try to enhance root growth is yet to be seen. These will be good specimens for our short Toronto-area growing season. All are going outside in the cabana/gazebo tomorrow, will sit for a week or so (low temp in foreseeable future is 5 degrees celsius), then in to the garden. Please so far, but the proof will be in the production. See pics below...

I decided to transplant some after a few true leaves and not transplant the rest. Can't say I noticed a difference. Certainly there was no tap root present on any when I planted them today.