Cherry tomatoes or ANY tomatoes seem to operate like Bonsai trees, and can produce without a lot of roots. HOWEVER, you will run out of soil in a tiny pot. If they sprout in your windowsill they will spread out their roots.
Consider leaving a tomato that you picked, and next year there are volunteers from the seeds. If you leave them alone they will grow together in pretty much the same place, happily.
I planted DD's one cherry in a pot with 1 ft of soil, about 14 inches high, about 15 inches diameter, and it has a basil friend.
I also planted a grape tomato in a similar sized pot, again, with a basil friend.
Both are sharing the dirt. I encourage them to water them as often as they can remember, and you will need to do the same in a windowsill.
Many people dig deep holes, like me. Others plants more sideways, like this:
Growing Horizontal Tomatoes: Introduction It is spring, time to think about tomatoes plants. Will you buy or grow from seedlings? How many plants? Do you want more tomatoes for your money? Do you want healthier tomato plants and fruit? Do you want …
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