I want my Opuntia Microdasys to conserve energy...

[Aichybatoal]

I've got a lovely little Opuntia microdasys var. minima, and just in the last growing season alone, he put out 3 more pads! But the thing is, they didn't finish growing during the last season, and should continue to fill out this summer. And that's fine, but just today I noticed that one of those new pads is trying to pop out its own baby pad! I don't want the cactus to expend more energy into putting out a new pad; I want it to spend all its energy on completing the ones it made last year. Is it safe for me to cut off the little bud before it grows in order to reroute my plant's resources into the couple of pads it already has? I know you can do that on tomato plants and angiosperm flowers, but does the same concept work for cacti? I'd love to know. I've included a picture of the brand new bud so you can see its progress so far.

[Steve Johnson]

I know you can do that on tomato plants and angiosperm flowers, but does the same concept work for cacti?

Nope -- maybe not the best analogy, but cacti don't respond well to the kind of "domestication" you can put plants like tomatoes through. Your Opuntia wants as much light as it can get. If you're keeping it outside with plenty of sun, let it grow however it wants to. However, if you're keeping it indoors, pinching off new pads is IMO going after the wrong solution to the plant's growing problem.

[Saxicola]

You are looking at those pads like they are a partially inflated balloon, which they aren't. They grew as much as they were going to grow last year. They may grow more this year or they may not, but the new pad isn't really going to affect that. If you want bigger pads then grow it outside for the summer. I think the reason the other pads are bigger is they were grown in a climate more conducive to that species. Growing it as a house plant is less than ideal. Obviously being in Chicago limits what you can do and I'm not saying you are doing something wrong, but the plant doesn't care about your limitations. It will only grow as much as it can under the conditions it is given.

[Aichybatoal]

Hey, that's really great advice. I'd really LOVE to grow my cacti outside, but I've always been worried about leaving them unprotected. I just feel like they would be so much more vulnerable to everything. Does that make sense? Or am I worrying way too much? I got this stupid little greenhouse from IKEA to keep my cacti in outside. It's pretty basic, but it works great, and I use it when it's sunny out. Should I be keeping my cacti in this, like, all the time (from April to September or so)? Thanks again for your advice.

[Steve Johnson]

Should I be keeping my cacti in this, like, all the time (from April to September or so)?

Yep -- that's the growing season for desert cacti. Opuntiads are tough as nails, so letting them get rain during that time is nothing to worry about. Since you live in Chicago, you should probably keep your microdasys inside over the late fall and winter, and don't give it any water when the plant is dormant. When the winter weather is done, take it back outside -- should grow really well for you then.

[Aichybatoal]

I also have a Golden Barrel and a Balloon Cactus. Can I leave all three of them outside all summer, like you said? Should I bring them inside at night? Are they in danger of being attacked by pests or animals?

[Steve Johnson]

I also have a Golden Barrel and a Balloon Cactus. Can I leave all three of them outside all summer, like you said? Should I bring them inside at night? Are they in danger of being attacked by pests or animals?

I don't have any personal experience with either species, but my gut instinct says yes -- all 3 of your cacti should be fine outside during the summer. While pests can be a concern, IMO keeping your plants inside year-round just to protect them from pests isn't worth the trade-off in terms of growth. If you do see any pest problems coming up, you can get help on how to deal with it here and here. Most animals won't be curious about investigating spiny things in pots. Rat and mice perhaps, although whatever "wildlife" I see here stays away from my collection. You'll just have to use your own judgement on the matter.

[Aichybatoal]

Thanks so much! I'll definitely keep them outside in the sun from now on! And I won't cut off that Opuntia bud, either. Great advice from all, and thanks again for taking time.

[A. Dean Stock]

I fully agree with the advice given above. The only additional suggestion I have is to make sure that the O. microdasys plant is not placed where people or pets could contact it. The glochids are abundant and could be dangerous if they contact the eyes of children or pets that might be tempted to get close for inspection.
Dean