If you buy tomato transplants from the garden center, choose seedlings with perky, rich green foliage and thick, sturdy stems. Avoid plants that already have flowers, as they are likely to be suffering stress. Make sure there are no woody patches on the main stem that may indicate that seedlings were over-watered or over-fertilized in the greenhouse. Seedlings fresh from the garden center are not ready to be planted directly into the garden right away. They need to be carefully exposed to outdoor conditions such as hot sun, wind, and cool days. I set my seedlings out on my front porch during the day where they get part sun and not much but some wind. I take them inside at night. I do this for two or three days and then they are ready to face the real world.Buying tomato seedlings
Harden off tomatoes prior to planting