Hello, how are you? My velvet touchez Sansevieria is dying. I had 7 of them and one started becoming soft and pale green, and turning like its friend in the picture. Please tell me how I can fix it
That plant was intended to be very short lived. The container is far too shallow, the tips are painted, and it is in need of many things.
First, I would put that into a standard container. A cactus and succulent mix with a little compost will be perfect for soil. They do not like to remain wet, and will tolerate drought very well.
This with proper care should fix all of the issues for quite awhile, until it needs repotting with fresh soil for nutrients.
All tubular types have the same care. This article will help you to grow tubular Sansevieria: https://www.gardeningknowhow.com/houseplants/snake-plant/starfish-sansevieria-care.htm
2 new offshoots have grown. They look very cramped. Should I separate them out and put each into their own pot? Thank you.
That is a type of sansevieria called Bowstring hemp and will tolerate cramping just fine. Moving the pups will give you separate plants, leaving them will give you one very full plant. Most people leave them and let them multiply.
This article will help you: https://www.gardeningknowhow.com/houseplants/snake-plant/snake-plant-propagation.htm
I have propagated some sansaveria: the original cuttings are still in the pot. How do I eliminate these stubs that still exist without damaging the new growth?
Normally when you take cuttings from a snake plant, the leaf is removed at the base of the plant, so as not to leave any stubs. Can you cut the stubs off at the base, without disturbing the new growth too much? You don't need to pull the stubs out.
https://www.gardeningknowhow.com/houseplants/snake-plant/snake-plant-propagation.htm
This new arm is sort of segmented with short thorns every couple of inches. I have cut the whole arm off and potted the whole new plant at the end more than once…works fine. My question is, does that segmented arm have a whole new potential plant in each segment? If I leave that weird arm attached will it continue producing new plants at the end? Or just die off?
As with any snake plant, you can cut off a leaf at the base and cut it into multiple sections for rooting, either in water or soil. It is important to keep the top of the leaf always facing up, i.e., don't plant a section upside down.
If you are removing the new plant at the end, and want to leave the arm attached, I would guess it would grow another pup at the end. I couldn't find documentation of that, however. But other types of succulents can do that like the donkey ears.
https://www.gardeningknowhow.com/houseplants/snake-plant/starfish-sansevieria-care.htm