Basil: An Herb Society of America Guide
Outdoor Cultivation
Starting from Seed
To sow basil seed in the garden, Thomas DeBaggio and Susan Belsinger recommend sowing seed "close together" but not touching at about 1/8 inch depth. This spacing may seem very close, but plants will need to be thinned later to spacing similar to that appropriate for transplants after the appearance of the first set of "true leaves" (24).
In the South, direct seeding is often not practical due to "unpredictable rainfall" (45). Heavy rains can wash away seeds and seedlings before they have a chance to become established. Instead, Southern gardeners may prefer to transplant or grow in pots (45).
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