Dot from NC writes: In zone 5, N. C. when is best time to plant lavender, and then to harvest it for a variety of uses?
For your zone, I recommend planting the lavender in early spring, after all chance of frost has passed. Your zone is better suited for the hardy lavender varieties. I don’t think I would recommend planting any tender lavenders in the ground, although you certainly could plant them in containers and bring them in for the winter.
You’ll want to harvest the buds just when they’re starting to open. In your zone, I suspect that would mean late spring through mid-summer. You will want to harvest them in the morning, on a dry, cool day. (If it’s raining or extra humid, your harvest may mildew before it dries fully and you definitely don’t want that!)
You’ll want to keep an eye on your lavender plants over the winter. If they’re planted in a location where the ground freezes and thaws several times over a winter, you’ll want to put mulch over the plant to help protect the roots. Planting the lavender in a spot where it can get the best air flow will help as well, with the humidity you experience in the summer.