Mixing equal parts of peat moss, compost and potting soil will produce good results. Tamp the soil down lightly to remove air pockets and water it. Keep the soil in the sunny window. Plant your basil only after the soil is warm (above 60 degrees) by sowing seeds directly into the pot, or transplanting seedlings.Water your basil regularly to keep the soil moist, but not soggy.Water deeply, until water drips out of the bottom of the pot. Don't allow the soil to dry out completely between waterings.ixing equal parts of peat moss, compost and potting soil will produce good results. Tamp the soil down lightly to remove air pockets and water it. Keep the soil in the sunny window. Plant your basil only after the soil is warm (above 60 degrees) by sowing seeds directly into the pot, or transplanting seedlings.