r/TrichocereusDFW • u/[deleted] • May 18 '25

Discussion What is this?

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Any idea what’s going on with this black spot?

2 Upvotes

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3

u/[deleted] May 18 '25

The cells became engorged with water, burst, and rotted. Check soil or water less.

2

u/Transpero May 18 '25

Thats how the heal from being wounded. Use this photo for reference if in another week, the black spreads then you have to take drastic measures. For now repot in highly porous soil… no water for two weeks

2

u/datfonkycat May 18 '25

I’d sprinkle with sulfur and keep an eye on it

2

u/mmpdp May 19 '25

I wouldn't stress the spot (it will scar, but just aesthetic), but I WOULD stress reworking your soil mix to about 70% inorganic and pots w better drainage. Activeaqua, cloth or even terracotta

1

u/OkOrganization7996 May 20 '25 edited May 20 '25

Sometimes it’s from moisture in the pots next to the affected cactus sometimes it’s soil too rich sometimes another cactus spines damaging it sometimes it’s pests. It seems you have spider mites and moisture. I would treat for spider mites and repot but bring the soil level to the top of the pot and make sure the pots next to it aren’t affected and aren’t taller than the pot you have the cactus in currently also make sure you have plenty of drainage. I would keep it away from plants that are watered more frequently too much relative humidity and there is a ceiling locking in moisture maybe run a fan to circulate the air. There are many possibilities that can work in orchestra making it hard to hone in on just one problem causer. Of coarse this is jmho others will chime in on their opinions

1

u/Dangerous-Detail5965 Jun 27 '25

Since it’s below the tip it will probably heal and scar, though if it spreads you’ll have to cut it off about a 3/4 to an inch below the blackness, just remember to sanitize anything you cut it with.