I keep reading that wood mulch is not a good idea for many agastache. Does it matter that much? I will switch to pea gravel in the beds I want to replant. I lost my rupris and apricot sprite last year.
Agastaches, especially the red to yellow long-tubed forms do need drainage and air on their roots. A raised bed is advised, and if you can get expanded shale/slate pellets, this would be even better worked into the soil. Pea gravel will work as a mulch. Hardwood bark mulch, in moderation, will break down into a humus they can use.
All the plants that died were in a raised bed with sandy soil. I did put hardwood mulch and last year it was hot and very dry. I guess I am trying to figure out why they failed so badly. Maybe I just over watered the bed due to the extreme drought. Also, the plants were planted in the fall so they should have had time to establish some roots before the heat of summer arrived.