How do I care for my Lavender plants?

Where are you? As in what zone? Not all lavender is green, some are a gray green, some are gray white like dusty Miller, depends on variety of lavender. They will perk up in spring. They need lots of sun too.

Thanks for your information. I’m in Alabama. All plants were same variety. Plants get full sun.

A few general tips for growing lavender.

First, I'd check to see if you have a State College Agricultural Agent / Extension Service. Ours is via Virginia Tech. They are a great source for info on any planting / growing / recommended cultivars, etc.

Second, it is worth getting in touch with The Herb Society of America

https://herbsocietyorg.presencehost.net/

is their website where you can find some information on specific plants as well as whether there is either an HSA Unit in your area or a Member at Large in your area, either of which would be great sources of information.

Third, general growing information. Slightly different for potted rather than in garden beds. Lavender needs well drained soil, ample sunlight. Some major problems for them are over watering , too much humidity, and insufficient airflow. The cultivar you are planting may make a difference as well. Virginia Beach is in zone 8a. You need to check yours.

First, soil. I use a mix that is roughly 1/3 good topsoil. 1/3 humus, 1/3 coarse builders sand. The builders sand is larger grained than playground / sandbox sand which tends to clump and hold water. The combination provides a good mix for support, nourishment and drainage. I then mulch under and around the plant with the sand about an inch thick and a collar which is about 5 inches. A friend does similar but uses white gravel instead. Both of these will reflect sunlight back up into the branches.

Airflow helps keep fungus from growing on the plant, which will damage / kill the plant. Sounds like you don't have the problem yet, but will as they grow. Normally I use the 4th of July to prune out branches if the mass of them is tightly together and hindering airflow. I'll also tease off any of the grey, ill looking foliage, clean it out from the plant. Depending on humidity, you may need to do this more than just once a summer.

Cultivars make a big difference. The English Lavenders you see grown commercially in the UK for perfume are in an extremely small but very arid part of the country. Hidcote and Munstead are common varieties. In high humidity, these tend to do poorly. "French Lavender" or lavendin do well here. They tend to have longer leaves and larger flowers. Dutch, Grosso, Fat Spike and Spanish do well here