Basil: An Herb Society of America Guide
Indoor Cultivation
Water
Basil requires lots of water but must also have proper drainage. As general guideline, water when the soil begins to lighten (24) or become flaky (25). Don't wait until your basil is wilting.
Watering needs will vary depending on your region and the developmental stage of the plant (45). If you are nurturing young seedlings in a Southern greenhouse, you may need to water as often as two to three times a day (45). Otherwise, watering every couple days can suffice (8). Keep in mind that if you use clay pots, basil may need to be watered more frequently.
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