Pink flowering Raphiolepis indica/Indian hawthorn and orange Strelitzia reginae/bird of paradise, in every parking lot. Fine separately, but please, not together.

I'm wondering if your pot has drainage holes? Not sure what you mean when you say you planted in "a 12 gallon stone container with 1” of pebbles underneath". If the stone container does not have drainage holes it's not suitable as a planter. Agree with Patty that the volume of the container is much too large for a band. Usually bands go into 1-2 gallon pots & are shifted into larger ones as the roots fill the container. Often another ingredient is added to the potting soil/compost/manure mixture, to keep the mix from compacting & ensure free drainage & oxygen for the roots, such as perlite or pea gravel. Twelve gallons of potting mix without that extra would likely stay fairly wet below the level of the rose even if the top portion around the rose allowed evaporation. If the stone container is glazed, that seal will prevent the bulk of the moisture from evaporating. My best guess is that the volume of your mix is keeping the soil too wet & that souring is what your leaves are reflecting. I'd replant the band into a 1-3 gallon pot, depending on current root volume. After repotting the rose, you could scoop out enough of the soil in the stone container to be able to elevate the rose's new pot above the remaining soil. When I want to display a rose in pretty pot that's too large for it, I use a nursery pot the proper size for the rose & use something else to elevate it in the pretty container so it looks like it's planted directly when it's not. Typically that's a stack of nursery pots upside down with the drainage holes aligned with those of the pot that actually holds the rose. If the pretty container is too wide for the rose's pot, a hanging basket pot of wire or plastic of the right width can go beneath the rose's pot & the differing widths be hidden with sheet moss. Welcome to the forum, Kim!

I water her once the top two inches of her soil is dry and I keep her in front of an east-facing window. I run the humidifier pretty often as well, keeping the room at a humidity of 60-70%. I also mist throughout the day. She only has one new, healthy growth and the rest are either stunted or growing very slowly and I can’t tell LOL are they not growing because of those dry edges?! :( One of my Calathea’s was just infected with spider mites. I’ve since then isolated her but maybe it wasn’t soon enough, which means... could those issues be from spider mites?! I’ve inspected her soil pretty closely and I’ve only found a few baby gnats (yikes!) which I’ve since then sprayed a bit of neem oil solution on her soil. Haven’t found any sign of webbing either. Please help!! I just want her to get better. Thank you!!

The brown and grayish areas are from frost damage and an opportunistic fungal infection. The rhodies are not used to cold weather yet or you got unusually cold temperatures. Keep giving them TLC. No fertilizers while they are stressed. Once they begin to leaf out, give them a little Holly Tone for azaleas at half strength. I would throw away in the trash all the leaves that fall down as soon as possible to minimize spreading fungi. Do not fertilize late in the growing season so they harden in time for winter.