@gardengal48 (PNW Z8/9) is there something in the soil that produces that coloration?

I think that is O. Santa Rita, they seem to be characterized by those gorgeous colors (I think especially after cold temps).

Not the soil but a natural pigmentation that increases intensity with stress - like cold or drought. You can see them all over the Palm Springs area showing off that purple coloring and not much cold there :-)

btw, the common name for O. macrocentra is purple prickly pear. I also think this is santa-rita as macrocentra has very long spines, which I don't see in the photo

They are everywhere here in Tucson, Az. I love them! I have 4 pads I'm tying to root.

Hi Jojo, I also love mine and can't wait for it to get bigger. A neighbor has one that's about 5 feet tall!

I keep looking for a pink one but I only see it in other people's yards. I don't want to ask strangers for a "cutting," but I may have to.

Have you seen any for sale in Arizona?

Hi JoJo!

No I haven't seen a pink one yet. If I do I will get us some!

Great -- I'll give it a try as well!

Actually, many (if not most) plants will start turning their leaves reddish/purplish in response to cold weather. This is because as Winter approaches, many stop producing chlorophyll in preparation for dormancy (allowing other Fall colors to show through). This also makes their leaves more vulnerable to photo-oxidation though, and so the plants will often produce anthocyanins as a substitute sunscreen.

For example, here is a Hummingbird Bush as freezes started hitting:

Around here (Tucson, Az.) this purple prickly pear maintains most of the purple year round, It is more intense in the winter

Same here in Nevada -- the color is not seasonal, but its intensity may change slightly depending on watering and temps. They also come in pink and ruby red.

I guess I’ll be odd one out and say I don’t think that’s Santa Rita which I’ve grown for many years. The base pads look too olive green instead of grey green like Santa Rita. Also the pads of pictured plant look smaller and thicker than my plants which have thinner bigger pads. I’ll post pic of my plant taken today so you can see. I do love Santa Rita though!

My Santa Ritas also look slightly different. Their pads are actually fatter and rounder... Also, they both look identical, except one has oversized thorns and the other one is almost thornless. But they are greyish, like yours.

It's a very frustrating group to identify...

Around here they have the oversized thorns.

I just came across a few the other day in a web site and now I can't remember which one. lol