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Gardening

Tall cactus

(4 Posts)
Auntieflo Sun 12-Jul-20 11:36:21

Good morning, and I am hoping that Gillybob may be able to answer my question.
I was given this cactus, by an elderly neighbour, about 2months ago. I did pop it into another pot, as it was only in a plastic one.
It seems to be growing, and is 14 inches tall, from the soil to it's tip.
The thing is, it seems to be wanting to grow out of the soil, if you see what I mean. Right down at the base of the plant, it is dark and a bit bare of prickles.
Am I doing something wrong?
Will try and attach a couple of photos, and hope for some guidance.
I don't even know what sort of cactus it is.?

Farmor15 Sun 12-Jul-20 20:19:34

I think the main thing about growing cacti is to keep close to a sunny window and avoid over-watering. If it’s too far from bright window it may be more inclined to stretch up and get lanky.

Esspee Sun 12-Jul-20 20:42:06

Could it be rotting at soil level due to overwatering?
Did you use potting compost when repotting? It holds water so is not suitable for cacti.

NanTheWiser Sun 12-Jul-20 21:20:36

As something of a cactus expert (two large greenhouses full of them), I can tell you that it is Cleistocactus straussii, and the browning and loss of spines at the base is normal, just ageing.
It should be potted in a very gritty mix (John Innes 2 or 3, plus fine grit @ about 50/50. Don’t let it stand in water after watering, and give it the sunniest windowsill you have, to prevent it stretching (called etiolation).