6. Transplanting Seedlings Into Larger Pots

Posted on by

When do you know it’s time to transplant?

Transplanting seedlings into larger pots will allow them to develop larger and stronger root systems before they are planted into the vegetable garden. Do this after the seedlings have their first true set of leaves and a good developing root system. Depending on the seed variety, this is between 2 to 4 weeks after sprouting. That first little set of “leaves” you see aren’t true leaves, they are called cotyledons or seed leaf. According to Dictionary.com they are: A leaf of the embryo of a seed-bearing plant. Cotyledons either store food for the growing embryo or absorb food that has been stored in the endosperm for eventual distribution to the growing parts of the embryo. Here you can see the cotyledons and the first true leaves.

For transplanting seedlings, this picture shows the right stage of a seedlings growth including the cotyledons and first true leaves.

What size pot should you be transplanting seedlings into?

You should be transplanting seedlings into containers that are 2 to 3 inches larger than the cell or container they were started in. Usually, a 3 to 4 inch pot is the right size for most vegetables. This will allow room for root growth and will help prevent overcrowding of plants competing for sunlight. Your pots can be actual nursery pots, yogurt cups, paper or plastic cups, almost any clean container as long as you have put drain holes in the bottom. Without drain holes, the soil can remain too wet and can result in mold, fungus or root rot. i.e. dead plant.

What about fertilizer?

The seedlings get fertilized about a week after transplanting, and every two weeks after that. Use a natural fertilizer at 1/2 strength for now. Once planted into the garden, follow the directions on your preferred fertilizer. Incorporating good compost into the outdoor garden beds will reduce the amount of added fertilizer needed. Natural and organic is always better.

Transplanting seedlings can be a bit messy, but not difficult.

  1. Prepare an area to work in. Spread out some newspaper on your table to make cleanup a bit easier.
  2. Water your seedlings to make it easier to remove them from their cells or small pots.
  3. Prepare your potting mix by pouring it into a large container and dampen it with warm water. Warm water absorbs better and you don’t want to shock your seedlings with a cold mix.

    Table is ready, newspaper down, pots, soil and plants are ready.

    All set up and ready to start.

  4. Fill your new containers 3/4 full with moist soil and tap the container to settle it. Make an indentation in the center that is big enough for the root ball.
    Pots are filled with potting mix.

    Pots are all filled with potting mix.

    Photo of indentation in soil for root ball of seedling.

    Indentation deep enough for root ball.

  5. Remove a seedling by tipping the cell on its side, use one hand to support the soil and then tap it from the bottom. If it is a soft plastic, you can press up on the bottom. If it is not releasing, use a dull knife inserted down the side to loosen it. Handle them carefully, don’t pull on the stem as this can injure the seedling.

    This photo shows the seedling with attached root ball.

    Seedling with attached root ball. Note the roots starting to wind around at the top. Caught them just in time!

  6. Carefully holding a seedling by the stem(s) and leaves, place it in the indentation and add more moist potting soil around the root ball and firm the soil lightly. If the root ball is taller, you may have to make a deeper indentation in the soil. Don’t bury it any deeper than it was in the original container. The exceptions to this are peppers and tomatoes. These can be planted deeper, right up to the cotyledons. If you have more than one seedling in a cell, plant the seedlings and root ball intact. Don’t try to separate them. Wait a week and snip off all but the strongest seedling at soil level. This way, roots are not disturbed or damaged.
    Seedling placed in soil.

    Seedling is about the right height in pot.

    The seedling has been planted and the soil lightly firmed in.

    Additional potting soil has been added and lightly firmed in.


  7. Tap the pots of newly planted seedlings lightly to settle the soil around them and add a bit more soil if needed.
  8. Water from the base, start fertilizing in a week and then every two weeks until they are ready for the garden. Watering from the bottom prevents soil compaction and helps prevent fungus from growing on top of the soil.
    Photo showing watering into the base of the tray.

    Watering from the base of the pots.

    When the tray is done, return it to its place under the lights. Be sure to label each individual plant, as they are easy to mix up with similar looking plants. Been there, done that…

    Finished flat of transplants ready to go back under the lights.

    Finished flat of transplants ready to go back under the lights.



    Secured website seal.

280total visits,1visits today