By Bev Johnson, Otter Tail County Master Gardener
One day, you are happily watering plants and discover that one of them has done a striptease -- all the leaves are on the floor. Another looks like a cotton plant, and you know you don’t have a cotton plant. A third is so sticky that the leaves are turning black, and the cat is stuck to the floor beneath it. You can either pitch the offending plant out into the nearest snowbank, if you can find one, or attempt to save it.
Start by giving any affected plant a good bath. Put a drop of either liquid dish soap or Safers, insecticidal soap, in a deep pan or bucket of warm water. Put your hand on the soil, then tip the plant over and swish it in the soapy water. Rinse well. This will kill many bugs and clean the dust off the leaves as a bonus.
If the plant is too big for this treatment, wipe each leaf, top and underneath with a cloth dampened first with the soapy solution then with clean water.
If the plant has aphids, their spit is the sticky stuff on the floor, you can usually wash them off by holding the affected leaf or stem under a stream of cold running water. This works outside too. Hose them off. They are not strong enough to climb back up.
A plant with mottling or streaking on the top of the leaves and a filmy gray dust on the bottom has spider mites. Spider mites just love our hot dry winter homes. Give your baby the soap treatment then keeping the area around the plant humidified will help to reduce the numbers of these microscopic spiders. They especially love soft-leaved plants. Keep the affected plant in isolation as these little stinkers do like to migrate.
If you notice hard barnacle like lumps on the stems of your plants, you are really in deep do-do. These scale insects are armored! They can’t move. You can simply scrape them off with your fingernail if there are just a few scales. If the plant has more than you can scrape off, chuck it and start with a new scale-free one. If the plant is a favorite, you can try this. Mix a solution of two tablespoons of your soap, and half a bottle of Tabasco sauce in a quart of water. Spritz it on the leaves, leave it overnight then wash it well. The object is to dry up the scale, however it also dries out the leaves so wash it well.
Mealy bugs make your plant look like it has begun to sprout cotton. The white fluff is actually fine, white, waxy hairs. The fluff is designed to repel predators and gardeners. If there are just a few mealy bugs, dip a cotton swab in rubbing alcohol and wipe them off. If it looks like an explosion in a pillow factory, try the tobacco spritz.
Since you don’t eat your house plants, you can use a systemic chemical in the soil that is sold for treatment of roses. Dispose of any soil with this nicotine derivative in it in the garbage, not in the garden.
Whatever the bug problem you are dealing with, just one treatment will probably not cut it. Keep an eye open for further invasions and treat it as soon as possible. After all, sticky floors from bug spit are not only tough on your cat, they attract dust and mother-in-law’s hard looks.
When you do get a new plant, keep it in isolation at least 2 to 3 weeks to be sure it is not infested. The best run green house can inadvertently sell buggy plants.