Prepare a sunny planting area in the spring after the soil temperature rises above 70 degrees Fahrenheit. Cultivate the soil with the garden spade down to a depth of 4 to 5 inches. Add about 3 inches of aged compost over the surface and work the compost into the soil thoroughly. Rake the planting area smooth.
Plant the basil seeds in rows, spacing each seed about a quarter-inch apart. Space rows about 12 inches apart. Cover the seeds with 1/4 inch of soil.
Water the soil gently immediately after sowing the seeds. Keep the soil evenly moist during germination time -- up to three weeks.
Thin the seedlings after they grow to about 2 inches, removing the weakest seedlings to leave basil plants growing about 8 inches apart in rows.
Allow the soil to dry slightly before watering again, and then provide water to saturate the soil evenly.
Remove the lavender blossoms with the pruning shears as they appear, to prevent the basil from becoming bitter. Use the blossoms in salads.
Clip the top third of the basil stems from the plant and use them in savory dishes as you would use any basil herb. Sweet Thai basil is ideal in Asian and Thai cuisine.
Cut the entire basil plant down to the soil level at the end of the growing season. Use the fresh basil leaves, freeze them in plastic bags or dry the stems upside down in bunches.