QUESTION: Can you start carrots in seed trays? When will you need to transplant them? -Tiff R.
ANSWER: Carrot seeds are naturally slow to germinate, but you can speed up the process by priming them indoors. You can grow carrots in starter pots, or flats, but if you do, make sure to use seed starting trays that are at least two inches deep and don’t forget to move them into the garden when the seedlings are only one or two weeks old. If you wait longer than two weeks to transplant carrots, the newly-developing taproot will likely be stunted or disturbed during the move, which usually results in an unsuccessful harvest.
It’s relatively easy to speed up the germination process of carrot seeds by priming your seeds indoors. Three or four days before you are planning to plant your carrot seeds, soak them in room temperature water for one hour and then place them on a damp paper towel. Fold the paper towel so that it holds the seeds inside, and place it into an airtight container. Keep the container stored in a room temperature location and plant seeds within three to five days after priming them.
Start your carrot seeds indoors in high quality potting soil, that is finely textured and densely packed into starting trays that are at least two inches deep. Sow two seeds per cell and thin to one if both seedlings emerge. Once the seedlings are three-fourths of an inch long, gently pull the whole plug of soil out of the tray and plant it in the ground. If the whole plug falls apart or the roots are damaged, you may end up with damaged, or forked carrots.
The reason that transplanting carrots is such a tedious task, is that as soon as the seed germinates, it begins developing its elongated taproot. That’s why it’s so important that your carrot seedlings be moved into the ground very early, because once the taproot reaches the bottom of your starter tray and is blocked by the container, it will stunt the development of the root, which can be devastating to the development of the plant, especially its ability to produce a tuber.