Whether you start your own flowers from seed or purchase seedlings from a nursery or garden center, proper care is necessary to ensure that they survive until they are transplanted out to the garden. Seedlings are more tender than mature plants and often cannot tolerate too much cold or heat. They are also more susceptible to pests and drought conditions. Caring for them correctly also ensures that they continue to thrive once outside and throughout the entire growing season.
Keep seedlings indoors in cool, well-lit area until you are ready to transplant them. Set them where they receive at least six hours of sunlight, such as by a south-facing window.
Water the seedlings when the soil surface just begins to feel dry. Water until the excess moisture drains from the bottom of the seedling pots. Avoid wetting the foliage; water at the base of the plant. Empty the drip tray after watering, as standing water breeds disease.
Fertilize the seedlings beginning five days after germination and then every two weeks thereafter. Apply a soluble flower fertilizer at one-half the label-recommended rate.
Pinch off the top ¼ inch of the plant stems when seedlings are approximately 6 inches tall and have grown in at least three sets of leaves. Pinching encourages lateral stem growth and leads to stockier plants.
Prepare seedlings for transplanting outdoors. Set the seedlings outside in an area protected from high winds and direct sunlight once all spring frost danger is past. Leave the seedlings outside during the day, and bring them back inside at night. Gradually move them into direct light over the course of one to two weeks. This allows the flowers to adjust slowly to outdoor conditions.