When it comes down to it, learning to appropriately treat houseplant pests has a lot to do with experience. Whether it’s learning to spot problems before they start, to decide what treatment is appropriate, or when it might be time to throw in the towel, you’ll get better alongside your level of exposure to issues.

For this last installment in our series on dealing with houseplant pests, we decided to turn to our staff, who have a wealth of knowledge and experience on all subjects related to keeping houseplants. We talked to our plant health specialists to provide even more information on properly taking care of your houseplant pest issues.

Houseplant Pest Q/A

Which houseplant pest do you personally dread the most?

Absolutely and undoubtedly, it is thrips. They hide in the smallest of crevices, lay eggs in the soil, and spread rapidly. They can actually fly! They are hard to eradicate if you have a large collection, but it is not impossible.

Which pest would you say is the hardest to detect?

They can all be difficult to detect. Most of them have early larval stages where they don’t cause a lot of visible damage due to their size. When I started collecting plants, mealybugs surprised me a few times. You think it’s clean, you put it in your plant corner and two weeks later you see one on a new leaf. It can be maddening.

What’s something new you’ve learned about houseplant pest control lately?

Don’t be afraid to really go for it. It’s important to be consistent and to try multiple methods of pest eradication for the best (and quickest) results.

What should be the first course of action when you find pests on a plant?

Quarantine! When I find a pest, I immediately remove the plant from its location and put it somewhere where healthy plants aren’t. This ensures that it won’t spread. I always check the plants in the same area and sometimes even treat them if they are touching. An ounce of prevention is worth a pound of cure.

Are some houseplants more pest-resistant than others?

More so, I would say that some are more vulnerable than others. Some plants, like the beloved Hoya compacta, are absolute magnets for pests. So many hiding spaces in those curly leaves… I treated mine when I brought it home as a preventative measure. You have to be extra careful with Alocasia (spider mites, thrips) and leafy vines (mealy bug), as well as with any plant with super dry soil, like succulents. When plants go dry, it can make them extra vulnerable to infestations.

What are some common houseplant pest misconceptions of treatment mistakes?

People often use dish soap in homemade treatment recipes. If it’s is harsh enough to break down cooking oils, just imagine what it can do if you don’t get it all off of your plants! Of course, some people have had much success with this method of treatment. I have experienced varying results; some burned leaves, some mushy leaves, some shock. The process in general is shocking to the plant and ultimately, in my opinion, unnecessary with so many safe and reputable options available. Using a natural, pure soap like Castile soap is a gentler alternative to dish soap

Do you have any favorite tips, tricks, or tools for prevention or treatment?

If you are growing tropical plants indoors, I like to treat them before placing them within the collection. I like to keep them separated for about two weeks, because that’s how long it takes for a systemic pesticide to kick in. All the while, checking on the plant as usual to see if there’s anything you need to be aware of!

If you wanted to go a more organic route, I like to use Neem or Pyrethrin oils to treat any pre-existing problems. Some plants, however, are more sensitive to being covered in horticultural oil. Since I don’t grow my plants outside and there are no natural pollinators, I don’t mind using a systemic treatment.

For more information about houseplant pest treatment, be sure to check out parts 1 and 2 of our series!

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