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Repotting tomato seedlings might feel like unnecessary work if you just want to move things along, but there’s a good reason for it: This extra step allows you to take advantage of their remarkable talent to grow roots along their stems.
Tomato seedlings are unique in that they like their stems buried deeply. They have the ability to form new roots (called adventitious roots) along their stems, which help the plants grow more vigorously.
In fact, if you live in a humid climate, you may have even noticed adventitious roots forming above ground from tiny bumps (nubs) on the stem.
Yes, every single one of those bumps has the potential to be a root!
Given ample moisture and sunlight, these roots will continue to grow like the ones underground and can even plant themselves in the soil if they get long enough.
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