tray full of seedlings about ready to plant
Seedlings about ready to plant outside

I start my seedlings inside instead of buying them from the nursery. If you do the same, you must harden them off before planting, or they will die when planted.

What is hardening off?

Hardening off is the process of getting seedlings adjusted to living outside. Your pampered seedlings don’t know how to handle wind, sunlight, and the other parts of being outdoors.

The Process

Hardening off takes about a week, so start about a week before you want to plant your transplants. If you harden them off, then move the transplants inside for more than 24 hours for some reason, you have to start all over again.

  1. Put the seedlings in a sheltered, shady area for 1 hour, then move them back inside.
  2. The plants should be in the same spot for 2-4 hours, then come back inside.
  3. Move the seedlings to the same location and leave them out. They will not come back in again.
  4. Put transplants in the sun for 1 hour.
  5. Place the seedlings in the sun for 2-4 hours.
  6. Put the transplants in the ground.

Fertilizer

Before transplanting your seedlings, spread fertilizer for vegetables over the area and work it into the first 2-3 inches of soil. Vegetables are heavy feeders and need to be fertilized about every four weeks. Follow the directions on the package for how much to use. I use Espoma company (GT40) Garden-tone 3-4-4. I would advise picking it up at a nursery instead of mail because it is heavy, and the shipping adds a lot to the cost.

Water

After you plant your transplants, water them in. Wetting the soil around them keeps that soil from wicking all the moisture out of your plants and killing them. It also puts the fertilizer in the root zone for the new plants. The fertilizer gives them a boost and helps keep them from going into transplant shock.

Hardening off isn’t hard, just time-consuming. You have to plan a week out to do it before the transplants go in the garden or they will die. It would be a shame to let all that work go to waste.