Growing seedlings indoors has many advantages. It is possible to try plant varieties that are rare or have only recently been introduced. Many annually flowering plants such as petunias, begonias and celosias must be sown indoors.
The most important factors in successful growing are adequate lighting, appropriate temperature, high humidity and a light and sound subsoil. Even with the best seeds, results can be disappointing if these basic criteria are not met.
Consult the Horticultural leaflet on indoor seedlings.