On Friday, I talked about how the warmer temperatures and longer days were causing plants to put on new growth and tender new growth was likely to attract all kinds of insects. Today I’ll talk about how to cope with those pesky pests in a friendly way.
Interestingly enough, after I drafted that post (which I do ahead of time) I went to a garden center to see about adding a few new plants to my collection. You’ll see a lime that I picked up on Wednesday. It was the best looking lime in the garden center. It was also the one that had the fewest aphids on it. The rest were pretty much covered in almost every stage of aphid, from nymph to full-bodied creature. I really didn’t want to call attention to the situation or I would have taken some photos, but I did mention it quietly to the cashier when I checked out. Needless to say, I have this plant in quarantine and I am showering it off every few days.
So that’s obviously one way to deal with insects (but again, you have to keep your eyes peeled for these pesky critters!). Take the plant to the sink (or shower) and wash it off. It works best with spider mites and aphids and if the infestation is severe, you may wish to first treat the plant with an insecticidal soap and then hose it off to get the remaining stragglers.
Insecticidal soap is really a wonder treatment for mostly all the indoor pests. It will kill aphids, mealy bugs and spider mites. If you catch the infestation early, one treatment may be all you need. If not, repeated applications may be necessary.
Be aware that certain plants are more sensitive to treatment than others. Never spray when the plants are in the sun or when the temperatures are above 80 degrees (this is good advice for indoors or out!)
And if, for whatever reason, you see just one or two affected leaves, or an affected twig, sometimes the best practice can be just to prune those off. You can often stop an infestation in its tracks just by pulling off a few leaves. This is especially true for scale, which is difficult to treat once it gets started.
Scale protects itself with a hard covering. So, as I’ve often described it, you could spray straight Raid on the plant and it would have no effect (but please do NOT try that!). Instead, what you have to do, if the plant is small, is to scrub off the leaves with a toothbrush dipped in insecticidal soap.
If it’s larger, that’s more of a problem. A lightweight horticultural oil will smother the scale, but most of us don’t want to be spraying that inside the house. If you can hang on until you can get the plant out of doors, the wasps and hornets will eat the scale off the plant for you–or if you are not in an area where there are watering restrictions, you can blast it off with a sharp spray from the hose. Either way, locate the plant at a distance from the house so that you are not bothered if the wasps and hornets come to clean the plant for you! And vow not to think of these critters as pests in the future (or as less of a pest anyway!)
Organic houseplant insect control is very easy if you catch the infestations early. If not, sometimes the best control is what I call “triage”–I toss the plant before it infests the rest of my collection. Barring triage (a last resort, obviously), quarantine a badly infested plant until you determine whether it can be saved. But careful observation should help you avoid either of these steps!