Hi Dea..
Lets see if we can noarrow things down a little so the others can help.

The plant looks awfully shinny in the first picture. Did you put something on it to make it shine?

How often do you water it, and do you take it out of the blue pot so it can drain?

I have never amended a comercial mix, so we will have to wait and see what others say,

How long have you had this plant.?

Was it exposed to any sudden temp changes?

JoJo

This post was edited by jojosplants on Mon, Dec 10, 12 at 15:29

Dea,

That would be my guess - underwatering. Even with Opuntias (most of which are not fussy about what they grow in), I'd cut the MG with at least 50% perlite for them to grow well. Nothing particularly nasty is happening there - now if it were covered in mealy bug, that would be nasty (but you could make your own cochineal dye, so it wouldn't be all nasty).

It is shiny in the first photo because I used a flash jojo.
The second I didn't use the flash.
The leaves of this plant are fairly shiny anyway and the flash reflected it so it looked much shinier.
I don't put any thing on the leaves to make them shine.

I water it about every two weeks. And yes I take it out of the deco pot. The plant itself is in terracotta.

I started it from a cutting this spring...April I think.
No sudden changes in temps.

Cactus....LOL, I think I will skip making dye. I really detest Mealy bugs and scale. I have probably been over cautious with the water. I will re-pot in the 50/50 mix and be a little more generous. If I can ever find what I need for the gritty mix I will get going on that.

Thanks so much both of you.

Dea

I know Jojo hates this, but having a moisture meter, $9 at your garden center, could answer the question if this was over- or under-watered. Ok, shoving one's finger down the dirt works pretty well too, but, if you have topdressing that you don't want to disturb, a little probe does the trick. Merely watering biweekly is not a good indication of whether a plant is under or over-watered. A change in weather and bang!, your biweekly watering will kill your plant.

Jeff, I never use perlite for my plants. I pretty much always use 75% pumice, 25% commercial cactus mix (with some changes depending on the plant of course). What's your recommended mix? Why perlite? I know people use perlite so I am not criticizing your choice, just curious to learn.

Jeff, correct me if I am wrong, sir, but not all mealy bugs are cochineal insects (Dactylopius coccus).

And the mealies I have had over the years, even though I have Nopalea cochenillifera in my collection, have all been unsuitable for turning my lemonade pink, unfortunately.

Christopher

One alternative to a water meter is a toothpick. They're cheap and I bought like 1000 for $1. It's used in the same manner as baking. I find if there's any soil on it, the plant is still moist. When it comes out dry, it's time to water. This proves more difficult when you have a deep pot though... There's nothing wrong with a moisture meter, this is just what works for me and it's another way to check for moisture.

I agree, you can't water based on a schedule as certain factors will cause your plant to dry out at different rates different times of the year. Also, when you water, it's best not to give it little sips but water it thoroughly and then let it dry out before watering it again.

Planto

Planto..I do use the wooden toothpicks also..you can get the inexpensive wooden skewers for deeper pots, they are around a foot long. That is what I use to judge weather my HP need water. I am just not really sure how much water C&S really want/need. Obviously the Opuntia needed more. I re-potted in a more open mix (50/50) as suggested and watered thoroughly. It is perking up today. Thanks everyone.

Dea

Robin,

Most folks don't have access to pumice (like me) - perlite is a semi-acceptable alternative. Believe me, I'd use pumice (and roughly in the proportion you use) if I could get it.

Christopher,

You're correct - there are hundreds of species but very few that are suitable for dye-making.

Dea,
I'm glad to hear it has perked up. Thanks for the idea about the wooden skewers, I need to get one for my ZZ Plant.

I would think that most C&S would be dormant right now so they wouldn't need as much water, but I understand if they stay relatively warm or are winter growers, that doesn't apply. Keep is updated on your Optunia.

Planto

Thanks, will do Planto and you are welcome. I was glad to see the improvement this AM. I am heading south (SC) soon for three weeks and get nervous about leaving my plants with the sitter. He does a great job following my directions to the letter but hate to leave him with an ailing plant.

Dea

One can even use a pencil as a way to check for moisture if one has no skewers or chopsticks around; it's the same idea.