You can start seeds in a sunny room, or grow them underartificial lights. Here's how to grow your own seedlings. Seed packetsusually provide information to help you determine the best time. Callyour local Extension Service or weather service to find out the averagelast frost date in your area. Annuals tolerate cool weather but not frost, so wait until after last frostto plant them outdoors.
Hardy annuals withstand light frost.
Also, some plants don't like tolose momentum and will fail to thrive if you wait too long aftergerminating to plant them outdoors. Keep in mind, too, that your timing will probably not be exact. In addition, seeds that are started indoors may be influenced by variables such as temperature,sunshine or cloudiness. Ideally you should use containers that are at least two inches deep,although shallower containers are OK for slow-growing plants. Recycled containers should be washed in a solution ofone part bleach to ten parts water.