Basil may be grown from seed sown early indoors and transplanted outside after frost, or sown directly in the garden, or planted as a potted plant.
Sowing Seed Indoors:
Sow basil seeds indoors 6-8 weeks before the last frost in spring using a seed starting kit
Sow seeds ¼ inches deep in seed-starting formula
Keep the soil moist at 70 degrees F
Seedlings emerge in 7-14 days
As soon as seedlings emerge, provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day, off for 8 hours at night. Raise the lights as the plants grow taller. Incandescent bulbs will not work for this process because they will get too hot. Most plants require a dark period to grow, do not leave lights on for 24 hours.
Seedlings do not need much fertilizer, feed when they are 3-4 weeks old using a starter solution (half strength of a complete indoor houseplant food) according to manufacturer’s directions.
If you are growing in small cells, you may need to transplant the seedlings to 3 or 4 inch pots when seedlings have at least 3 pairs of leaves before transplanting to the garden so they have enough room to develop strong roots.
Before planting in the garden, seedling plants need to be “hardened off”. Accustom young plants to outdoor conditions by moving them to a sheltered place outside for a week. Be sure to protect them from wind and hot sun at first. If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. This hardening off process toughens the plant’s cell structure and reduces transplant shock and scalding.
Sowing Directly in the Garden:
Direct sow in average soil in full sun after all danger of frost when the soil is at least 60 degrees F.
Remove weeds and work organic matter into the top 6-8 inches of soil; then level and smooth.
Sow seeds evenly and cover with ¼ inches of fine soil.
Firm the soil lightly and keep evenly moist.
Seedlings will emerge in 7-14 days, possibly longer in cooler soils.
Planting in the Garden:
Select a location in full sun with good rich moist organic soil.
Prepare the bed by turning the soil under to a depth of 8 inches. Level with a rake to remove clumps of grass and stones.
Dig a hole for each plant large enough to amply accommodate the root ball.
Carefully remove the plant from its pot and gently loosen the root ball with your hands to encourage good root development.
Place the top of the root ball even with the level of the surrounding soil. Fill with soil to the top of the root ball. Press soil down firmly with your hand.
Use the plant tag as a location marker.
Thoroughly water and apply a light mulch layer on top of the soil (1-2 inches) to conserve water and reduce weeds.