Herb plant starts are commonly available at nurseries and garden centers, but growing herbs from seed is so much more rewarding! They provide a fresh supply of aromatic flavor and spice all season long. Purchasing herb seeds allows the gardener to cultivate those rare and specialty herb varieties that aren’t available just anywhere.
Starting herbs from seed is no different than starting other seeds. Some herbs, like basil and cilantro, can be direct sown after the average last spring frost in your area. Other herbs, like rosemary, sage, and thyme, are best started indoors, several weeks before the last frost.
To sow herb seeds, prepare a seed tray or pot with moist potting soil. A good rule of thumb when sowing seeds is to plant the seed twice as deep as the seed is big. Most herb seeds are small, so cover the seeds lightly with another layer of potting soil, just enough to allow some light to come through.
For quicker germination, you might want to place seed trays on a heat mat to raise the soil temperature to 70°F, which is optimal for most herb seeds. You might also consider topping the seed trays with a humidity dome to retain moisture in the flat. Bottom water the trays or mist lightly to water, to avoid spreading the seeds too much and potentially washing them away.