Hi there, I'm new to these forums and to keeping plants in general. I received a small cactus as a gift last summer (not even sure what kind it is, so that information would prove useful if someone could identify it for me) and while it's been perfectly fine for nearly a year and actually grew quite a bit, it's starting to shrivel up. I don't think it's never really rooted particularly well, it's felt pretty "loose" in the soil but I've never kept a cactus before so I wasn't sure if that was normal or not. I just noticed it this morning. Instead of being a "barrel"-shape, it's more of a cone-shape now. And I believe that it also feels "soft" instead of firm to touch which wasn't the case before. It sits on a window sill that gives it a few hours of sunlight each day and I think it's watered once every 10 days with tap water. Is that too much? What could be the issue here? Is it rot, poor rooting, poor nutrition? Any answers would be greatly appreciated.
It is some kind of Notocactus, perhaps scopa but I am not sure. They usually do not shrink much in winter, especially not if watered. If the plant has become thinner while not growing taller, then it is a bad sign, especially if it feels loose. If it was mine I would remove it from the pot and look at the roots and the base of the plant. If these parts are soft, brown and rotting I would throw it away. So it has been watered that often throughout winter? While Notocactus often do better with a little water in winter, every 10th day is too much, especially with that big pot and peat-based soil, which holds too much water. It should be mixed with, for example, crushed brick, hydroleca, gravel or pumice. When I keep my Notocactus at room temperature in winter I give them a light watering about once a month (and I use a growing medium that dries out faster). If I keep them cold I don't water them at all until spring. As said, the pot seems too big, about 2 cm wider than the rootball is enough. And, as already mentioned, a pot with a drainage hole is necessary.
Thanks for the replies everyone. We did remove it from the pot and the roots (what little roots it had) were completely rotten. The pot does have a drain hole, but it seems that it was watered too much compounded with the moisture-holding soil. Would giving up and starting over be the best option?
You could cut back the roots up into the bottom of the plant until you find healthy tissue. If you do you should sterilize the knife and cut off a bit more. I don't think you will find any, however, and if you do the rooting process can be difficult for a beginner. A new plant is the better alternative, in my opinion. If it really is a Notocactus (sick cacti can be difficult to identify) it should flower relatively easily, here is one of my plants from that genus. The less water-retaining growing medium can be seen as well. :-)
