In general, the best time to start sowing seed for plants which will reach maturity in the late fall or winter is in the early spring months of March and April. Seeds sown during these months should produce plants that are hardy enough to be set out in the garden (or in window boxes or on the porch) by the time summer comes. They will get the benefit this way of the summer outdoors before their first season in the house.
Set out your pots on a table, providing one pot for each kind of plant you plan to work with and fill them loosely with the vermiculite mixture you have chosen. Although not essential, it is a good idea to insert at the bottom of each pot a layer of drainage material such as pieces of broken pot, etc., to insure proper drainage. The mixture should be damp, though not soaking wet. With a tamper, which can be anything from a wooden mallet to a flat-bottomed ashtray or drinking glass, press the surface of the mixture gently until it is smooth and the top is roughly a quarter to half an inch below the edge of the pot. Then place the seeds not closer than a quarter of an inch apart. Some plants, such as Begonia, Petunias and Gloxinia, have tiny, almost powder-like seeds. These can be left uncovered on the top of the soil. Bigger seeds, however, should be covered by sprinkling a layer of starting mixture to a depth roughly corresponding to the diameter of the seed sown. Use the tamper again to press the surface lightly, thereby assuring a good contact between the seeds and the soil. Make sure that the tamper you are using is completely dry, especially with the tiny seeds, or else it will pick them up, thereby spoiling the job you have set. out to do. Always use a new pot for each variety of plant you are going to grow, as the germination time for various plants differs considerably.