Growing Zinnias Inside From Seeds

Fill two 2 1/4 to 2 1/2 inch peat pots with sterile potting mix until the mix is 1 inch from the top. Lightly tamp the top of each contained potting mix with your hand to help it set and to remove trapped pockets of air. Water the growing medium until excess flows out through the drainage holes at the bottom of the pots. Discard this drained water.

Plant two to three seeds of your desired variety of zinnias 1/4 inch deep in each pot. Cover the seeds lightly with 1/4 inch of the growing medium.

Cover each pot in a plastic wrap and wind an elastic tie over the opening to seal them. Mimicking the effects of a greenhouse, the bags retain heat and increase the chances of germination.

Set the containers in a warm spot with temperatures between 65 and 75 degrees Fahrenheit. Ensure the spot receives warm, indirect light. Inspect the containers every day to ensure the growing medium remain evenly moist at all times, or water lightly whenever needed. Remove the bags when germination occurs, which usually takes six to 10 days.

Maintain exposure to indirect but bright light as the seedlings grow. Water the containers whenever the soil surface feels dry to the touch. Turn both the containers every other day so the seedlings grow upright toward the light.

Thin out the seedlings in each pot to one when they grow their second true set of leaves. Select the strongest, straightest seedling and clip the others off at soil level using sharp scissors.