Same here with the mosquito dunks in the rainwater barrels. My broms are potted and I just periodically tip them to drain the wells. Mosquitoes will definitely take up residence in them. I know some folks that put a few Mosquito dunks crumbles in their bromeliads to prevent that. I'd not heard to use coffee grounds before.
Back to the mulch, in the south it not only preserves the moisture content it will help keep the soil and roots cooler. I use what is commonly available here and don't purchase any other.
Good topic! I've read and enjoyed this thread ~ thanks!
