dying cacti, please help

[londoncacti]

Dear Cacti community.

I have had these 5 cacti for 10 years. They haven't been re-potted in years and I only give them tap water (no food). Unfortunately they all look ill. I am most worried about the one with lots of 'prongs'. It also seems to have 'cobwebs' all over it.

I have been watering once per week-I have done lots of reading and it appears that is too often. The only window ledge in the house is just above a radiator and so I haven't kept them there, however I easily could.

Any advice would be much, much, appreciated.
Many thanks
Ella

[Benyellow]

I'm suspecting etiolated growth due to insufficient sunlight, the base appears to be rotten. If it is indeed rotten, you could try propagating the cactus from cuttings, give them enough sunlight. I'm not an expert, this is base purely on my experience.

[iann]

Watering every 10 days is too much, even for this bigorous species. Maybe OK in a porous clay pot in summer, absolutely too much in winter. It wouldn't hurt to feed once in a while, but that is the least of your problems if it has rotted.

Take a couple of the healthiest offsets to root as insurance. Then tackle the rest of the plant. If the base is rotten then you'll have to cut it away and see if there is anything left to save.

I'm only seeing one picture. Cobwebs might be cobwebs. Or they might be spider mites.


Your cacti need direct sunlight to grow well. See what you can manage. If you have long dark winters, maybe that is the time to move them somewhere cool even if it is not sunny. If you keep them cool enough and dry in winter then they won't grow and it won't really matter if you keep them in a cardboard box.