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whats-wrong-with-my-cactus-21938731

Cactus 1

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Hi! Both of these cacti live outside, south facing, 6 hours a day of direct sun, and have been doing fine, but recently both started becoming discolored. What could be causing this? Thank you!

Comments for What’s wrong with my cactus?

Oct 30, 2020

No idea
by: Jacki Cammidge, Certified Horticulturist

You aren’t giving me enough clues, so I can’t possibly tell you what’s going on. You need to say where you are.


Oct 30, 2020

I’m in Southern California
by: Karen Harris

Hi I’m in Southern California I believe zone 10


Oct 30, 2020

Weather?
by: Jacki

What’s your weather been doing? Right now, if you’ve got brilliant sunshine, it will be coming at a different angle, as the days get shorter. So it stands to reason that the plant is getting sunburned. That’s what I suspect is happening. They may seem to be in full sun for most of the day the rest of the year, but if they are under an overhang, this would shade them – until now.


Oct 31, 2020

They’re in the ground.
by: Karen Harris

Cactus 1 gets some shade but cactus 2 gets full sun. It’s been unseasonably hot until about a week ago.


Oct 31, 2020

There you have it…
by: Jacki

That’s what’s going on then. They are responding to higher light levels by getting sunburned, due to less leaves on surrounding plants, plus the change in the angle of the sun.

If this doesn’t seem to you to be the cause of the problem, you’ll have to resubmit your question with more details.

If it does appear to be the cause, then you may need to move the plants so that they get much more sun at all times, leaving them less susceptible to the changing conditions in the fall and winter. Other things you could try; putting a light shade in front of them, and covering the white wall behind them with sticks so it doesn’t reflect heat and light onto them from that side.