I have two Fusion Calathea plants in 4" pots, can I put them together in a 7" pot?
You can plant them together, but I would go with an 8 or 10 inch pot. Those are beauties.
They need well draining potting soil so you can add some sand to help. They like bright, indirect light and high humidity. Let the soil dry out between waterings. They are supposed to be an easy plant and are pet friendly. Fertilize monthly when actively growing but not in winter.
Does it mean they are dead? What can I do?
Here are some things you can try: Make sure you are watering enough; they like moist soil. Also, change to distilled water. Tap water contains additives like chlorine, fluoride, salts, and minerals that your plant may be sensitive to. Also increase the humidity by misting the leaves or adding a pebble tray beneath. You also can tidy up the plant by removing any dead, damaged or brown leaves.
Here is more:
https://www.gardeningknowhow.com/houseplants/calathea-plants/peacock-plant-care.htm
The leaves have drooped really low and many leaves are yellowing. I had recently repotted it trying to fix issue but didn't help. Please help.
This is likely to due improper watering, and inadequate root space. I would put that into a larger pot, and make sure to allow the soil to dry out down to about 1/3 of the way down into the container between waterings.
This article is for its close cousin, but it has the exact same care:
https://www.gardeningknowhow.com/houseplants/calathea-plants/calathea-zebra-houseplant.htm
What is the name of this plant? It seems to like the shade best.
started to get crispy brown leaves. I don't think it has root rot, and I keep the humidity on the higher end. Can anyone tell me what I'm doing wrong? If this is the wrong place to ask a houseplant question, please let me know. My room has two large east facing and two large south facing windows, so it's bright for the whole day. I keep the calathea on a shelf on my desk, where it gets bright, indirect light almost every day. I water it when the top inch or so of the soil gets dry. I have 3 humidifiers that I run whenever the humidity gets low. I've cared for calatheas in the past and currently have an Orbifolia that's doing well in a similar spot. If it makes any difference, the rattlesnake is on the same shelf as a hoya and a spider plant. I recently moved it from a slightly darker spot next to a philodendron hastatum (Silver sword). Any response is appreciated.
I see a key piece of information... Repotting... Once you repot your plant, that soil will not be colonized by roots. This will mean that it takes longer to dry out, and will cause disease faster. Until the roots colonize that portion of the soil, I would water less than usual. You might even wait until the leaves droop, slightly, to water. Unfortunately, your photos did not come through, so I am unable to see the damage in question. I do suspect damage from overly wet soils, deeper in the container. Be sure to use a fungicide, just in case, as it can help prevent issues, as well.
his collection of articles will help: https://www.gardeningknowhow.com/houseplants/calathea-plants
This will help you with fungicide use:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm