Can you transplant prior to true leaf development? Yes. Many do it all the me including me.

Is there any benefit in skipping the interim transplanting? No but there is a problem that develops when you make such a big jump in container size. The roots aren't developed enough to cope with all the moisture that will be retained in the big cup of soil. Transplanting needs to be a gradual increase in container size.

If you can provide enough light you could get away with going from cotyledon stage to the big cup IF you only put 2" of soil in the bottom of the cup and put the plant there. Then fill the cup as the plant grows.

But they are prone to leggy development from the shading of the cup sides.as it is difficult to get them enough straight-overhead light.

So yes there are distinct benefits for the plant to two-stage transplanting. Started cell to interim small cup and then to the big cups, deeper transplanting each time.

Dave

Thanks, Dave. The red cups are 3 1/2" diameter, 4 1/2" deep. What size would you recommend for first transplant?

Gary

Last Saturday/Sunday I separated and transplanted my tomatoes that were just starting to grow their first true leaves into 8.5 ounce styrofoam cups. In just a couple days they were starting to take off. Unfortunately today the greenhouse I had them in tipped over due to the high winds (I meant to stake it but forgot), spilling two thirds of the plants out of the cups and so I had to replant them again. From the ones that spilled out, I could see that most of them had root systems that were twice the size as when I first transplanted them.

Long story short, I think 8 ounce cups are a good size although still a little big. If you can find non-paper and non-clear cups in the 5 ounce range, I think they would be better.

Rodney

Edit: For clarification, when I said "spilling two thirds of the plants out of the cups and so I had to replant them again" I meant that I replanted the plants, not that I planted new seeds.

This post was edited by theforgottenone1013 on Tue, Apr 1, 14 at 17:10

Gary - it depends on the size of container you started them in. For ex. if started in 6 cell packs (1 1/2" x 1 1/2") they can go to 6-8oz cups, again not completely filled but filled as they grow.

But if bulk started in flats like I do with 100-150 cotyledon seedlings in the tray or like many do with 20 seedlings in one shallow plastic butter tub then they first go to cell packs first.

The general guideline is up no more than 2x the size they are currently in. 1" goes up to 2", 2" to 4", 4" to 8" etc. Follow me?

Obviously there is some room for flexibility in that but you just don't want to make a BIG jump up in size.

As Rodney found, they kick start within just a few days with staged transplanting.

Dave

It is more cumbersome to do several transplanting but in the end it works much better in my experience. I have seedlings with first couple of true leaves in regular growing trays for a bit. For me it is matter of space. After about April 10 when weather a bit stable, i.e. nights do not dip lower than 40 all the time I have more space in my greenhouse so off we go for 4èpots. Depending on weather, planting times and whether plants are container dwarfs etc I might go to 8èpots next or straight into garden. I have done this for quite some time and find roots just develop better this way.

@garystpaul Tue, Apr 1, 14 at 9:12 My seedlings are between the cotyledon and first true leaves

Over the weekend I learned this new word. That bit of stem between the cotyledon and the first leaves is called an ''epicotyl ''.

Perhaps you can sense that it is too cold here to transplant seedlings so boredom has driven me back to undergraduate subjects.

Of course that's what I meant and should have written: My seedlings are at the epicotyl stage! Thanks :-)

Gary

I planted seedling in small trays and some grew quickly. Dave recommended on another thread to transplant them quickly before they get too leggy. So I transplanted in 4" pots but only filled half way with soil so that I can keep adding as they grow, t didn't occur to me to start with 2" pots. Dave, should be ok?
Thanks Sharon

Oh oh..I just read this. I am a newbie (first time ever anything gardening) and I went from cell to big cup. Hmm....these are pics before I transplanted them..

And these are 5 days later. They seem to be doing extremely well..should I be worried? :(

Another close shot

Should you be worried? I would be but it is your choice. It's like making your 1 year old toddler learn to swim by throwing him in the deep end of the pool. Will he learn to swim and make it to the side of the pool? Maybe. Then again maybe not.

Easy to fix. Dump out the cup and fill it only 1/2 way with the soil mix and re-pot the plant so that all the bare stem is buried. Then fill the cup as the plant grows.

dave

no they will be fine just as long as you don't overwater. Let them go dry between waterings and don't water them until the cups feel light again. Pick them up and see. The main reason why most of us bump things up and bump them up again is space. The final frontier. I have 30x30 greenhouse, 26x36, and 26x96, and 10x20 and guess what, I'm out of space!

Thanks Dave and Sandy...Hmm this is going to take some figuring out. Maybe I'll do half Dave's way and half the way I've been doing just to make sure I don't royally mess myself up. Oops! lol

Suvoth, what is the size of the cups you planted into? Just curious (top diameter, height, or ounces).

Thanks,
Gary

They are 18oz, 4 inch diameter, 4'3/4 inch height. When I transferred them to the cups, I transferred at about 1/2 height and buried most of the stems as I read about. so there is about 1/2 of the container on the bottom with new soiless mix and the rest I carried through with the seedling starter cup thingy and the topped with the soiless mix.

This post was edited by suvoth on Sun, Apr 6, 14 at 19:37

Thanks, suvoth. We're using exactly the same size cups, into which I transplanted 146 seedlings this morning. These are only a bit bigger than the cups I've used in the past for an intermediate transplant; what's different is that I'm going directly from the shallow germination trays into the 18 ouncers, being mindful of both the caveats and green lights from Dave and others. If I get around to it, I'll report on the outcome of this experiment. I'm using a fairly porous medium, a mixture of Pro-Mix and bark fines (the latter of which I make myself by running bark nuggets through a shredder) and will monitor the moisture level. (Let us know how your own seedlings fare, if you would).

Cheers,
Gary

I certainly will! I'm using Sunshine 4. Are you using the same colour even? That would be perfect lol

Oh, wait, I should ask how old your seedlings are? Mine are 17 Days old (from the moment I put the seeds in the earth, not from actual sprouting).

I believe some are making a bigger deal about this then it should be. I plant my seeds directly into 4.5 inch peat pots, (I have even done 6" peat pots) where they germinate, and grow until they are ready to go in the ground. I have been doing it this way for a long time. No intermediary transplanting. They stay in the pots for about 6 weeks. As long as you know how to water, you and your plants will be fine. Tomato roots grow so fast that the advice that the rootless soil around the plant will retain too much water for the plant to handle, is not a problem. Especially if you know how to water correctly.
One reason I use peat pots is because they dry out fairly quickly, which is what I want.
Some of this advice may be coming from commercial growers who value space as a premium, and therefore do not like to pot up to a large size too soon.
If we were speaking of a plant that had slow root growth, then the fact that there is a lot of soil in the pot w/o roots is a problem, because it stays in this situation for a long time. But not a big deal for fast growing tomatoes.

Fingers crossed ;)

In light of some of the comments made by one poster above I need to clarify that this is not just my opinion but something that is well-known in the industry and that has been discussed here many times in great detail over the past 8-10 years. It isn't new information. The many plant health and circulatory benefits of staged transplanting is well documented and not just by we commercial growers who grow hundreds of plants annually.

So one might want to pull up the past discussions here on 'potting up' and 'staged transplanting' and review some of the many research links included in those discussions before labeling it no big deal.

It is easy for some some growers to fall into the trap of this-works-fine-for-me when they have never even tried the alternatives. Or doing what is easiest for them rather than what is best for the health of the plant, and then they wonder later why their plants consistently succumb to disease and other problems year after year. Whether one is growing 10 plants or 1000 plants isn't the strongest plant with a well developed root system the goal?

So suvoth, yes do it both ways and then make note of the differences in root development when you go to put them in the garden. Note the #of leaves and the color of the plant, the diameter of the stems, and then the health of the different plants as the season progress. That way you'll truly know what works best for next year. And do please come back and report on the results just as some others here have posted above.

Good luck with your plants. :)

Dave

Will do :) I'm a bit scared to move them as the soiless mix is sooo crumbly but I will try! :D

Facts:
I was a commercial grower for 15 years for one of the largest growers in the Country.
I grow some of the largest, nicest tomato plants in my area.
Any advantage of increased root growth by transplanting them in stages is offset by transplant shock, broken plants, lesions...
My plants have roots coming out of the peat pots after 4 or 5 weeks.
For a plant that grows roots as quickly as a tomato does, your general rule is not necessary to stand by.
Root growth comes down more to knowledgeable irrigation techniques more than it does if one chooses to sow directly into a 4.5" pot as opposed to trays.

I would agree with ncrealestateguy about repotting being optional. I have been starting my tomato seeds indoors under florescent lights in 4 inch transplant pots set in a watering tray with a gentle heat mat underneath. After the true leaves show, I give a once a week liquid fertilization with 1/2 strength seedling fertilizer. In only 3 weeks the plants are large & vigorous with lots of roots and ready to transplant outdoors. I choose a mild spring day to plant directly in my raised garden bed, and place a red Wall of Water/Kozy Coat around each tomato plant to reduce the shock of direct sun and cold night temps. The plants absolutely flourish! The plants consistently produce flowers within one week of planting out in the garden without need of hardening off. I find I am one of the earliest to have ripe tomatoes in my area.

I plant only heirlooms, which are the most susceptible to disease, yet, they do very well. They are very vigorous plants. I reside near Sacramento, California, with commercial tomato growers throughout.

Alright ...follow up time Dave. I chickened out and didn't replant my plants :( sorry! I started to replant one and it got all crumbly and a mess and I said no way. I'll have to try your methodology next year. In the meantime, my plants seem to be really taking off. Question for you guys. How long can I keep them in the Solo cup before I have to transplant in a larger pot? How will I know they are root bound without actually taking them out of the cups? I mean, They've only been in the cups for 12 days so far...

Another shot

When is your plant out date? Those plants are getting pretty large for your zone and just guessing about 4 to 6 weeks till last frost. You can slip one out of the cups in a week or so and it should hold together pretty well, then inspect the roots that are growing around the the cup. I'm guessing you will have to move up to an 8 inch pot before you get them in their final resting place.

My last frost date is 20th May (so about 6 weeks out). My plants are only 23 days old (from beginning of germination attempt). I'll try your method in a week and see if they come out of their cups easier. Thanks!

23 days from seeding? What are you feeding those things? Look nice and sturdy.

I potted up my peppers (started about the same time as your tomatoes, March 15-16) today but they're not nearly as sturdy. Of course, they take longer to germinate and grow more slowly than tomatoes. Some don't even have their first leaves yet but I had to separate them (multiple seeds in same cell germinating days apart).

Later this week I'll probably pot up the tomatoes I started on the 29th, still have some germinating that I started on the 6th.

I've fertilized them twice (1/4 strength then 1/2 strength) with Miracle Gro Tomato. My pepper plants are 23 days old too..here's one of mine. King of the North Bell pepper plant

Now that I think of it. I think it must be a combination of things. I don't have a heating mat :( but I have been using a air heater on them 24/7. Watering only when I need to. Fertilized every week (except I may just skip this week altogether) in the water. I live in a basement with no natural sunlight and this is my first attempt at growing so I didn't know what to expect. I've been using Cold Fluorescent shop lights on them 16 hours a day.

This year I have potted all my seedlings, as SHARON mentioned a few posts before ; That is from cotyledon stage or even from paper towel to 4" pots, half filled then added more soil as they grew. That is what I have done with peppers and tomatoes. And they have done fine.

The nurseries and commercial growers might a good reason for going in small steps and that is managing space for maximum production and ease of maintenance. It is easier to care for them in a small room, on a few shelves than all over the greenhouse. I think it is quite possible to germinate seeds in say 10" pot (one seed per pot). Seed does not care or know how big the pot is. But for grower, it takes a lot of space. That is why a 1 1/2" by 1 1/2" cell is a logical choice for the first transplant.

Lots of discussion here. I actually repotted a seedling that was in a 4" pot because I felt I hadn't buried it deeply enough. I was worried but it survived. I then managed to push some of the seedlings down further in the pot and continue to add soil. I prefer planting deeply, as Dave suggested. There are a couple of seedlings that might have to bump up to a bigger pot, but I'm tapped out space at this point. I agree with seysonn about the smaller pot. I went to a 21/2" pot for some. I may soon have to transplant into a 4" pot,but I don't intend to go bigger unless I absolutely have to, and remember to use a fan or pass your hands over the tops to get sturdier stems.

Just wanted to share an update on my tomatoes and peppers. At 35 days old...so 5 weeks old:

Peppers

Suvoth, just a question. Regarding your lights, I read that when using the overhead fluorescents, it's a good idea to use a warm and cold light combination, although your plants look good, they might be a touch spindly. I use a compact florescent, full spectrum which gives the range of colours. I'm not an expert but just wondering.

I know I may not always do the correct thing when planting but I start with a 1 1/2 "x 2". starter trays and then transplant into 4" pots about a week after the first true leaves form and leave them in them until time to plant out.
I have them under T5 lights and fertilize with half strength solution every two weeks until I put them in the ground and everything seems to work fine for me.
Here they are today at about 58 days from sowing.

I figured I would post my Peppers also. :)

yes, I've heard the same Sharonie but my home depot and canadian tire didn't have the right bulbs so I had to settle. They do look a bit leggy but the pots I transferred them to were smaller height wise so when I transfer them to my big 7.5 gallon pots towards the end, I'll be able to bury the stem a whole lot :)

Amazing. My way is the only way! Right...

If you don't do it the complicated way, you're wrong! I don't do nearly any of that worried stuff and I have nearly full germination, strong plants, no setbacks, no damping off, no clever dirt mixtures, no watering formulas.

This is ONE safe way that works; just one. There are many. You keep them warm, you give them air, you flood them with light, you transplant them once (this "once" part is for your convenience as toms don't care one bit; they just want to keep growing), you never let them dry out, and you water them daily without leaving standing water.

It is not necessary to wait for the right phase of the moon, to measure ground minerals, to mix the proper soil using seven approved ingredients, to use three different graduations of pot size and the proper pot material, to drain the blood of a chicken, to fertilize a three week old seedling, any of those things. Millions of people grow it without all that fuss. It's just a plant.

Oh forgot to mention, nice plants cetompkins :D Look nice and strong.

Cetompkins... looks like you used Plant Growth Regulators on those things. They look like little rocks!