Can you? Sure. Should you? Meh.

If you have a very fertile soil, 2 plants occupying the same basic space, or very close to one another can work, but there are down-sides, and they often outweigh any benefits.

First, there are 2 considerations of space... above... and below - ground level.

Below ground level the roots compete for water, air, space, nutrients, etc... That competition can cause stunting of one, or both plants.

Above ground they compete for sunlight and air circulation. These factors can cause disease problems and slower growth.

So, if you decide you want to experiment, at least try to space the roots. You should expect smaller fruits, higher irrigation and nutrients needs, and the plants to be a lot more susceptible to disease.

I rarely recommend putting plants as close as you are thinking, but I often crowd. Properly done, although crowding can limit individual fruit size, it can increase overall yield. I never, though, grow more than one plant in the same space. I do sometimes crowd them as close as the species allows, but never on top of one another, the potential downsides are too great.

Agree with all of the above. Limited space can really be frustrating and it encourages many to over-crowd their plants. But more is not always better. Many times more is worse. :)

What are the effects? Increased disease and pest problems, reduced production, blocking sun, nutrient and water robbing, harvesting issues, etc. it's a practice to be avoided if at all possible. Standard recommended spacing for most tomato plants is 3-4 sq. feet with 2 sq. feet the minimum. Can you do it in less? Sure if the higher problems and risks are acceptable to you.

Dave

Thanks so much for all the tips. I think I'll spread them out as you all have suggested. Heading outside now for some garden fun :).

I planted 2 tomatoes in one cage in my early days of gardening because that is how they were when I purchased them. Together, they produced about the same amount as one plant. They were waaaay over-crowded and it was difficult to find the tomatoes for the foliage.

I have planted 4 tomatoes in a 3x3 foot bed. Even that is too crowded. Now, I space them out so I can see the tomatoes better and end up with better harvest because they don't over-ripen and rot before I see them. More space equals more tomatoes.

I have done a lot of close space planting, down to 18". It can be done but you have to do a lot of vertical support work ( staking or caging), plus leaf pruning and keeping the stems to 2, no more than 3.

So this year I am going to give myself and my plants a little brake by allowing 24" spacing. I support my plants up to 6ft. From there on ( toward the end of season) i leave them on their own.

Spacing at this scale is to accommodate foliage management. In 3 sq-ft area w/ about 14" depth) there will be over 24 gallons of soil volume, more that enough for any tomato plant. The more the space the more convenience for the grower. So if the real estate is no object, give them more space.

Here is a sketch showing the way I plant in a 3ft x 6ft bed, in a staggered fashion. The distance between the edge and the plants is 6" to 8"

Sey

Sey, that is exactly how I planted my beds when I was doing 6 to a 3x7 foot bed, but I neglected to mention that laziness prevents me from pruning, tying or doing anything other than picking. :) Glad you can make it work for you!!

Rebecca

Very helpful tips and thanks for posting the diagram. My raised bed is similar to the one you posted.

Good comment Sey and a picture or photo is worth a thousand words

You are welcome, Burn and Lar.

As I've said, if the real estate was not an object , I would space them 3ft and could have more fun than work. hehe.

I could've cut back on the number of varieties/plants but then I want to try so many different ones. Every year I say to myself that I will cut back drastically next year. So I hope 2017 will be the year. lol

Sey

Well with plenty of real estate and I am already saying "what are you doing". I have one tray with secondary leaves ready to be potted on with another right behind. It's going to be cold for the next few days and I would like to stay in but they are ready so I better get with it. Also better get compost tea brewing."this is funnn"

I put 5 plants in a 4x10 raised bed with 24" spacing and it still turns into a jungle. I don't prune much except the lower branches and sometimes a lateral branch or 2 that get out of hand. I can't imagine putting more than 5 in that bed.

I'm not saying I recommend it, but last year I had 27 plants of 3 varieties in a 4' x 14' bed. Harvested over 200 lbs (probably closer to 250. I stopped weighing, and I didn't weigh the grape tomatoes at all) of mostly heirlooms from that space. I'll have sauce for a very long time.

I can't keep my Cherokee Purple in check, they're out of control, even with limiting the number of stems. I would give them 3ft radius next time. My concern is lack of airflow in the bottom which can make it more prone to disease and pests, so I pruned a lot of the bottom leaves.

For cherry tomatoes though I don't mine packing them up and grow them single stem and tying them to stakes only.

Air Flow:

No matter how wide the spacing between the plants is, that might not guarantee good air flow. An unpruned plant can get so bushy that very little air can breath through it. I think it is essential to trim leaf branches up to 2 feet from the ground (top of soil) plus those inside that they won't even get much light anyway.

For airborne disease prevention, i do sprays with Daconil, Neem Oil, Copper Fugicide on a regular schedule ( 7 to 15 days, depending on the weather conditions). And do it right after plant out. You want to prevent infestation not wait and then fight it.

Sey

I have a special place just for my single Sungold plant. It is a 4'x8 raised bed that has 8' 2x4s attached vertically from the middle of the 4' sides. Starting at about 4' high I string coated wire horizontally across between the vertical 2x4s with about 6" between the wires all the way up to 8'. As the plant grows and vines, I tie the vines up to the wires using plastic strips cut from grocery bags. By mid July the plant is filling up the entire 8'x8' area and the vines start to double back down the trellis. It makes it very easy to harvest since the plant is spread out and not one big jumble of vines.

I tried 2 plants (one Sungold and one SS 100) in the same space one time but it was too much and too many and the plants grew together into a tangled mess. I couldn't tell what was a ripe Sungold and what was a SS 100 that was just starting to ripen.

I made the mistake of planting 3 Sungold together. It was a monster and could have easily taken up a 10'x10' space and been 10' high with the proper support. Eventually it just ate my 6' high trellis... grew up and over and back down and out of the garden where the deer kept it trimmed for me.

I'm not sure I will grow the Sungold this year. It takes up SO much space and by the end of the season it was a mess to clean up and they were all cracking on the vine or immediately after picking.

Yeah we too often tend to talk about tomato plant spacing as if all tomato plants were the same. Sun Gold is always a huge monster, biggest i have ever seen. So needless to say the spacing for Big Beef or Cherokee Purple or Rosella Purple or Better Boy etc could all be different. But most of us get around that spacing issue by giving each the same amount of space as we can whether they may need it or not.

The OP gave no varietal names. So in theory they could grow 2 Rosella Purple in the same cage (if we knew what they meant by a 'cage') but no way could 2 Big Beef be in the same cage. :)

Dave

I don't mind the splitting tendency of Sungold that much. I try to harvest at first blush which helps a lot. And if I miss some and they split, I toss them to my chickens. They don't seem to mind if they are split :). They also like overripe cukes, sun scalded peppers, and baseball bat zucchini!

Yeah I don't have chickens. It would be cool but we just don't have enough time. I often wish I could buy a farm.

For a good small plant variety I really loved the Jet Star last year. Good production semi determinate (produced an early flush but then continued growing anf producing) from small plants... 4 feet.

I've not grown JS, but I prefer smaller compact plants over vigorous indets that keep growing out of bound and produce much less fruits relative to their size. More and more I am moving to DETS and dwarf. This year probably half of my plants will be dwarfs and determinant or compact indets.They are much easier to take care of.

Sey