Basil seeds can be sown directly into the ground though all of July and on into early August. Warm soils lead to quick germination and you should be seeing small starts within a week. Prepare a smooth seedbed and sow seeds few inches apart. Don’t plant deeply, these are small seeds and need to be barely covered with 1/8″ of fine soil. Keep soil moist during the germination period. If weather is really hot and you are trying to keep soil from drying cover with newspaper propped a few inches above the soil. Sprinkle the seedbed and the papers to help hold in moisture during the day. When seeds sprout and show a full set of leaves thin 8″ to 12″ apart.
This late planting is what I use for frozen pesto and other preserved basil. It grows fast, is less troubled by slugs and needs little coddling. One of my favorite ways to preserve basil is frozen basil cubes. Strip leaves from the stem, and place in blender with enough water to make a thick slurry. Pour this mixture into ice cube trays and freeze. These can be stored in a sturdy zip-lock bag. Just toss in one or two cubes into sauces and soups for a burst of fresh summer flavor.