How can you tell from seedlings whether you are dealing with an indeterminate or determinate tomato?
Or when or how can you determine whether a tomato is an indeterminate or determinate tomato?
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The best way is to google it. If you know the name. Determinate types have one crop. Goes downhill from there. No difference in how they look. Although i don’t know any that are potato leaf types to be determinate.
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If your saving seed and planting I don’t know of any way without growing and see it’s life.
If you grow both I guess you could have crosses But if you are only growing indeterminates you don’t have the gene so don’t need to worry about it. Also remember that new hybrids take about 8 generations to stabilize. Keep seeds from the ones that have the traits you want. Best to grow out as many as possible. Each year you have fewer outliers but always possible even after 8 seasons.
Guys, i know the difference between indeterminate or determinate tomatoes. Do not have to google for that.
I have F2 seeds that will give about 75% indeterminate and 25% determinate tomatoes. Because we trellis and prune them different I want to plant all the same types in the same row.
The indeterminate tomatoes we will remove the suckers.
Thats why I want to know early what type tomato seedling I have?
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Thanks for explaining your reason for wanting to distinguish, it would be great to know when using F2 seedlings but I will be surprised if there is a practical method. If there is an easy way I think more of us would consider planting F2’s. If you find a method please post your results. Thanks
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If there was a forum for home vegetable breeders you might find an answer, but I suspect you may have to find the answer yourself with careful observation of growth habits of the very young plants and the separation of them that show distinct characteristics recording differences photographically as plants grow. Perhaps after a season you will have teased out the answer.
Yeah, you probably already figured this out.
There is a horticulturist at Stone Barns in Westchester county, NY that works with a Cornell breeder to develop a range of new varieties of vegetables. I think Johny’s sells some of their creations. You could probably locate the horticulturist by contacting Stone Barns. It is a 4 star garden to table restaurant created with Rockefeller money.
I bet you could also find an answer via UC Davis- I assume they are doing tomato breeding work- mostly to produce new determinate varieties for commercial production.
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I didn’t mean to google the definitions I meant say if you had seeds from Roma. Is Roma determinate? Easily answered by google.
Again without genetic testing you won’t know. No phenotype will tell you. That is your answer you are going to have to find a lab to do it.
Once they grow some you can tell but not as seedlings. Determinate are smaller plants with shorter difference between nodes. You may be able to tell by this. Determinates have more terminal flowers. Are much smaller stocky plants. But as seedlings I guess after observing a few generations you may see differences.
I think you need to wait till they flower to see if the terminal bud has flowers or not. I dont know of any distinguishable difference between the seedlings.
Yes @Fusion_power is probably the most like to know if there is a way to tell of those on this list. Looking at determinate, semi-determinate (what several of mine are said to be, but not really sure what that means) and indeterminates growing side by side in my seed trays I don’t see any obvious differences.
You may also want to join and post this question at http://www.tomatojunction.com where there are several other knowledgable people.
I absolutely know what you mean about growing the right type in the right way. I’ve mistakenly put a few determinates into my single stem growing trellis and by the time I realized it had pruned enough to greatly dimish the crop.
Sorry I can be more help and please let us know what you learn. I would love to be able to look at a seedling and know how it will grow so I avoid any future mistakes with where I place them and how I prune them.
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Yes there is a way. But!!! It depends on the original cross. Why?
There are several genes that affect the growth pattern of tomato plants such as indeterminate, compact indeterminate, determinate, compact determinate, dwarf, brachytic, ultra dwarf, dwarf brachytic, and micro dwarf.
If your cross is between an indeterminate and a determinate, the determinate plants will tend to set the first flower cluster between the 3rd and 5th true leaf. Indeterminate plants will tend to set the first flower cluster between the 5th and 7th leaf. This means you can pot the seedlings up into 1 gallon pots and grow them until they are roughly a foot tall. Separate out the plants that produce a flower cluster lowest on the plant and put them in your determinate row. Put everything else in the indeterminate row, but be aware that a few determinate plants may slip through.
When will this not work? If your plants carry the ft gene (fruiting temperature) they will tend to set flowers lower on the plant regardless of growth habit. If your cross involves one of the extremely early producers such as Bloody Butcher, the first flower cluster may be lower on the plant.
Here are a few more things to know about determinate and indeterminate tomatoes. Indeterminate tomatoes tend to set a flowering rachis every 3rd bud up the plant. In other words, there will be 3 leaves with a flower stem beside one leaf then the next flower stem will be in the next 3 leaves. Determinate plants tend to set a flower stem at each pair of leaves meaning 2 leaves with one flower stem. This is not an absolute. I’ve seen determinate plants with flower stems at each 3rd leaf. But under normal conditions, you will find that determinate plants set an average of one flower stem for 2 leaves. Determinate plants set a terminal flower bud about 3 feet up the plant. Once the terminal flower bud has been set, that particular stem does not lengthen any further. Indeterminate plants don’t normally set a terminal flower bud. This can be confusing when the plants involved are compact indeterminate or compact determinate. The simple rule to separate them is that a compact indeterminate is a smaller plant that never sets a terminal bud and a compact determinate is a smaller plant that always sets a terminal bud.
Want to hear about flavor effects of determinate vs indeterminate? Simple rule. The more leaves, the better flavored the fruit can be. But genetics is a lot more important. For example, Lynnwood produces superb flavored fruit growing right beside Celebrity hybrid which produces a ton of fruit but bland as cardboard store tomatoes.
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