Posted on June 14, 2009

Repotting (and Planting/Replanting) Tomatoes

My tomatoes started out this winter in little coconut pots in a seed starter kit.

I started way more than I would eventually need for several reasons:

• I wasn’t sure all the seeds would germinate.
• If I lost a few due to heat/water/disease issues, I wouldn’t lose that type of tomato entirely.
• I wanted extras to give away and sell.
• I could pick the best/most vigorous/most hearty specimen when it came time to plant them in the ground.

When you have that many starts and not all of them will go in the ground at your house, it is advantageous to start them in small pots in order to conserve space and energy/water/soil. Small pots also keep the water and nutrients next to the seed, which is planted in a pretty shallow hole, instead of allowing them to all flow to the bottom where a young plant can’t reach them.

I potted my tomatoes in rounds—the first round was into the seed starter coconut or cow pot, the second round was from the coconut pot into a 4″ pot, and then from the 4″ pot into a gallon pot (to be sold) or into the ground (for the ones I kept). What I noticed was that, although my plants weren’t as large and bushy as the ones being sold in the store, they had a very strong root system from the repotting and shorter stems which allowed them to take off quickly once they went into the ground and not need as much support structuring. Every time I moved the plant into a bigger pot with new soil, it had plenty of airspace to expand into with new roots. Additionally, I dropped the stem a bit below the soil level every time so that the plant formed roots out the bottom of the stem. If you were container gardening, I imagine you could do this up until the plant became too unruly to repot, creating a very strong root system and vigorous plant.

How to Pot/Repot/Plant a Tomato

Step 1: Carefully separate out your plants. I simply cut apart the plants in their coconut pots, but if you are removing a plant from an existing hard container, make sure to remove it without too much manhandling and without damaging the root structure. Either action could cause the plant to go into shock.

Step 2: Find the right planting depth. In the picture below, you’ll see the start of the root ball (soil level), a length of stem that is somewhat fuzzy, and then the first set of leaves.

The correct planting depth, in this case, would be about 1-1.5 inches up that stem, up to the set of leaves. Put a small amount of soil in the bottom of your pots to make your seeding sit in the pot so that the top of the pot lines up just under those leaves.

Step 3: Fill with dirt. Gently add soil (we used Rexius Premium Potting Mix) around the outside of the tomato seedling and give it a slight pat to keep it from moving when you add water. (Kids are great at this step—I explained to my daughter that she had to gently tuck the baby tomato into its new bed.) Then, water it.

This procedure should be repeated any time your plant outgrows its current pot, the roots grow out the bottom of the pot, growth stops, or when you are dropping the plant into the ground after the last frost date. I did this with both the tomatoes I started from seed, and the purchased seedlings that I kept in my garden window until planting day.