After dividing a supermarket basil plant, as well as growing from seed, I have around 40 of these. They like lots of water. I have most of mine on South-facing windows and they seem to need watering every other day. Not wet soil, mind you, but decently damp I would say. In comparison to my Mentha spicata, which I hardly ever need to water, I have found them to be thirsty plants.
They seem to be fairly resilient, too. I've had a few at the point of death and have managed to revive them under a grow light with water and they've come back beautifully. Pics, for example.
Basil Not Happy
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A Couple of Days Later
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I believe they are pretty much annuals, but I plan on propagating the best ones for use in the herb garden next spring.
