I bought my cactus about 15 years ago and I have to admit I knew nothing about them other than they didn't like watering very often. So he was watered infrequently. I was very naive. He would occasionally flower, and currently has quite a few buds appearing. Just recently I started looking into cacti more and feel really bad that I unwittingly neglected my little guy over the years. He's now getting much better care, has been repotted in special soil, and is watered more frequently in growing months and less in Winter. He appears healthy except for the fact that his spines from the bottom have all gone brown and brittle. This worries me quite a bit. He has always sat in my south facing bedroom window, which does have a radiator next to it. Could he be drying out? Is the heat causing this? We have an outdoor room that is much cooler, close to freezing in Winter, would this be better for him? Any help would be gratefully appreciated.
Cactus spines often change colour as they age, and spines close to the soil easily acquire a brown tint if the soil has a high humus content. Another reason could be that the plant has died, starting from the bottom. Time will tell ... Your outdoor room would be better for winter storage, assuming that the plant will not become wet, but the cactus should be prepared first. I stop watering mine in September and let them acclimatise to the lower temperatures in fall. Moving your plant into the outdoor room now can be dangerous if it has been watered the last 1-2 months. I don't think it has been dried out by the radiator, it should have looked much more compact then. Are the flowers white? The plant looks a bit like Mammillaria carmenae, but it is smaller than it should be after 15 years.
Thank you so much for your reply. The flowers are white. I really hope he isn't dying from the bottom up. I would feel so bad! I really didn't know anything about cacti when I got him, he's been moved about a bit over the years and watered sparingly. I didn't even know about growing periods or feeding, even that they should have proper soil. Just now I've taken off some of the dead spines to see underneath and it doesn't look good. The flesh looks all woody and light brown in colour.
Would it be possible that if he is dying, to cut the top part that is still green off and hope I can grow him back from that?
I agree, it looks as if it is drying up. If it really is sick it has probably spread too far, even if the upper parts still look good. If it is possible to cut off a healthy piece big enough not to die from dehydration then it is possible to root it, but judging from experience I would say that the chance is small.
