Last year planted elfin thyme to replace a lawn. We did new topsoil and then a layer of mulch which is what they told us to do. This year the plants were gorgeous, smelled great and were wonderful underfoot. But in the past two months they have started to die one at a time...turn black and wet inside and die. Contacted the people who set it up for us..we bought another 20 plants to put in between. Went to the nursery and they said we should never have mulched and use some compost. Removed all the mulch, used compost and now all the plants are dying one by one. I love the thyme. Please help.
Elfin Thyme in Lawn
Certified GKH Gardening Expert
This is likely a fungal issue and it may be to late to save the plants. Remove the dead and diseased material and dispose of.
You can treat with a fungicide to try to control it, but many times it will can remain in the soil.