Answer: Lavender is such a beautiful plant and the scent...heavenly. However, it is particular and doesn't care much for not getting it's way - a bit like those victorian ladies they remind us of: fussy, fussy, fussy. Lavender grows best in dry, almost arid conditions. It doesn't care much for fertile soil, so don't worry about enhancing your soil with organic material - it's one of the very few plants who won't appreciate it at all. Also, it can get "leggy" and look rather sloppyif fertilized or watered too much. Lavender absolutely demands good air circulation, and humidity will do her in. Regarding pruning, wait until you see new growth just beginning in spring, and simply prune plants to shape. On a personal note, I too live in zone 6 and I have never been what I would call successful with lavender. It is simply too humid here in the summer, so mine have almost always succumbed to mildew and fungal disorders. Be on the lookout for those.
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