Rescuing a much-beloved lavender?

Rescuing a much-beloved lavender?

Hello all! So I have a lavender plant (L. angustifolia, Munstead) that's about 8 years old, and did wonderfully all of that time. However, towards the end of the summer last year, much of the growth started shriveling and turning grey, from the bottom of each stem up. I belatedly figured out that this was most likely due to excessive moisture - I live in New Jersey, so the weather's very humid, in addition to last spring being unusually long, cold, and rainy. Now, the plant looks like it's survived the winter, but it's still looking pretty sickly - all of the old growth is shriveled and/or cold-damaged. Cold damage I'm used to seeing, but I'm anxious about last season's overwatering having caused irreversible damage. Are there any steps I can take to make sure the plant will make it this season? Am I just panicking? Thank you in advance!
3 rooms!

3 rooms!

my wall of rosemary

my wall of rosemary

What strategies do you use to keep track of your plantings?

What strategies do you use to keep track of your plantings?

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Growing Potatoes

Plants – Plus

Plants – Plus

My friend gave me a tree…

My friend gave me a tree…