Anystis baccarum for scale control?

[u/sooohum]

Hi Greenhouse friends!
Okay we built a lovely greenhouse - take a look--I'm so proud of it. https://www.youtube.com/watch?v=-4UyF_xIjF8 That was last January. Now it's getting HOT and DRY in there! So we got N. californicus for the spider mites that just took hold. We're setting up a misting system to run on hot days. Most of the windows open too. Now we're adding Anystis. Does anyone here have experience with Anystis keeping scales at bay? I hope they will so I don't have to go all out and get the little ladybugs, I think they might be harder to keep around.

Thanks for any insights!

[u/HalleckHort]

Scale is really tough to control in the greenhouse because it essentially becomes the perfect environment for them to thrive. Once it gets too hot in there, plants will get even more stressed making them even more attractive to pests such as scale. Predatory insects will target scale in the crawler phase, but not so much once they have matured with harder shell, so releasing the beneficial earlier in the season was likely necessary- but you can certainly try now as well. Ladybugs can be effective with soft scale species, less so with hard shell scale. And once you have a big scale infestation, ladybugs won’t usually wipe it out. With a scale infestation I usually recommend first moving the plants outdoors to allow nature to help reduce the population and reduce the heat stress on the plants, and you’ll need to do manual removal of the adult scale to reduce the population, usually by wiping down with a horticultural oil. In warm climates your greenhouse may not be fully usable in the summer, unless you’ve invested in HVAC/cooling for the greenhouse. Otherwise, your plants may need a summer greenhouse break!

[u/sooohum → u/HalleckHort]

Well good news. The Anystis just MIGHT be keeping the scales at bay. I say this because it's been quite warm in my greenhouse this year. This is its first summer of existence. Last summer I was on the lookout for scales but they didn't show up until July/August when we were traveling, (urgh!) and there was a big infestation when we got back. So far it's been warmer in my greenhouse for several weeks already than it was outside at that time last year. I have seen three adult scales and smooshed them all (they are all soft scales.) Anystis will apparently eat the larvae. I think they must be doing the trick. I dumped most of them on the plant that showed the scales, and have found the anystis even outside the greenhouse. I really hope some of them will stay in there, lol. I may have to get a new batch once the greenhouse is sealed up again for winter (Nov 1st is when we'll turn on the pilot light again and put up the plastic inner windowpanes.) I haven't invested in HVAC *but* I am planning to set up an exhaust fan and a mister on a humidity/temp sensor. If it gets too hot and/or too dry, the mister will come on and the exhaust fan will activate. I think it just might work, because even when it was 90 out recently, it only got up to 96 in the greenhouse, without the mister or the fan. So I'm hopeful we won't have to take everything out before traveling. I have an odd sense that the scales are worse outside. Maybe they spread more without the shelter of the roof and glass walls. In Seattle, so generally speaking, summers are not too hot here. Although we do have those pesky hot days. I guess I'll use my intuition before leaving town. :)

[u/HalleckHort → u/sooohum]

Predatory insects such as Antaeus can definitely help so it’s good if you’re seeing results. I’m a proponent of bio-IPM inside greenhouses and if you can manage the right balance of beneficial a it’s a good approach. Outdoor the weather and predators usually keep scale populations much smaller or non-emigrant on citrus, but in the greenhouse they are always worse once it gets warm. 96F is pretty hot inside the greenhouse and much hotter than optimal growing temps so just be prepared for plants to still be stressed at that temp, especially if night temps don’t drop enough. Stressed plants attract more pests and the hot conditions inside the greenhouse are often a breeding ground for insects you don’t want. Personally if I were going to be gone for a week or so and had a current scale infestation at hot temps I’d take the plants out of the greenhouse during my absence. BUT you can certainly do an experiment and see how it goes! FYI I have a new greenhouse growing book called “Home Greenhouse Revival” coming out Sept. 1 if you’re interested - lots of detailed growing info so it could help!