Last year I planted a long sphagnum pot with Basil - Thyme - Basil. All three did well and the basil very well. But I thought the thyme was getting an awful lot of shade from the tall basils, so..

This year I moved the thyme to its own pot (where it promptly died) and planted Basil - Basil - Basil. They're doing okay, but not nearly as well as last year. The question is, "Why?"

I renewed the soil when replanting so it is essentially the same as last year. Sun and watering is about the same too.

Theory: The basils suck water which kept the pot dry (sphagnum pot dries quickly anyway). Thyme seems to like it dry...

Theory: Thyme acts like alfalfa in a wheat field, replenishing nitrogen.

Could it be that basil and thyme just get on well together?