The Ins And Outs Of Houseplants

One of the routines that you should be into as a plant person is the annual ritual of remembering your houseplants. Remember the ones that have been cooped up inside accumulating dust and haven’t had a shot of fresh air in who knows how long? Remember the plants that you took outside last May? The ones that have been thriving in the tropical heat and humidity and exposed to aphids, beetles, slugs and a host of other bugs and baddies that just can’t wait to get into your house for the winter? Well, it’s time to get the innies out and get the outies ready for in. And maybe it’s time to get some bargains along the way.A few weeks ago I wrote about finding bargains this time of the year on trees, shrubs and perennials, but it’s also a great time to pick up a wandering Jew, a Swedish ivy or a ficus or two. Some of these plants will surely be leftovers from the summer that for one reason or another didn’t sell, but you can grab one now, trim it up, give it some tender loving care (just don’t love it too much with fertilizer) and by next spring you’ll have a magnificent plant that can be moved outdoors or put on a patio or porch.

Keep in mind though that cutting back some of these bargains is the key to success. Since they are slowing down with the season you can do some trimming and shaping, and then the plant has the winter season to slowly regain its shape and composure. This technique is particularly helpful with viney baskets of wandering Jew (or wandering Charlie if you don’t take to the religious type of plant), grape ivy and Swedish ivy, as these can all be cut back to the rim of the basket with a pruner. As long as they’re not over-watered and over-fed and they’re given bright but not full sunlight … they just may thrive.

And then there’s that special geranium that you’ve got in that large clay pot that you’d really like to “hold over.” Well, you can do that and more. It too can be trimmed back before coming inside to a bright or sunny window where it will sprout new branches. Truthfully, these branches will get kinda leggy through the winter months, and they may or may not flower, but come early March you can take cuttings at the tips and have several of this summer’s favorite geranium potted up for next summer. With geraniums, though, keep in mind that if you keep on pruning them back selectively until January, you’ll get more and more new shoots, and each new shoot is a potential cutting and new plant.

Ah, but there is a rub. With any of these plants you want to do a full inspection to make sure you’re not bringing unwanted guests into the house for the winter. Aphids and spider mites are probably the two most common plant vagabonds, because aphids can fly from plant to plant, and the spider mites can be carried on just a wisp of wind. Search them out now, and get them under control, or you’ll be cursing them in a few months.

Mealybugs shouldn’t be a problem unless you buy a plant that has them from a nursery or they’ve moved from one plant to another by being in intimate contact with the other plant. They’re hard to control, so if you find them on a plant that you’re considering bringing in, maybe reconsider.

Scale (which is related to mealybugs) are really difficult to spot, and like mealybugs they infest slowly and once indoors are virtually impossible to control. Most scales have a hard outer coating that can protect them from contact insecticides, and systemic insecticides work great but just aren’t available to us anymore. The other problem is that scales are most vulnerable in their crawler stages, and that can be hard to spot unless you know what to look for and when. However, the scales can be smothered, so keep reading to find out how.

Also, when moving plants or buying them, check under the pots for signs of slugs and snails. You may even want to pop the plant (well-rooted of course) out of its pot to see if there are any critters inside the pot. If you see snails, or slugs, now is the time to apply some bait, organic or chemical, to control the slimies before they become houseguests. Also look for any caterpillars, earwigs and centipedes in and under the pots, since they are easy to dissuade now but will just adore your windowsill in January.

Now, for the guys you’ve got indoors that are still manageable enough to get outside … get them out. Give them a bath or a shower and maybe oil them up a bit. Oil them up? Yes, oil them up. One of the safest insect sprays to come along in years are the new ultra-fine horticultural oils that can be used on houseplants (and virtually all other plants). These oils don’t have to be ingested by the insects like chemical poisons, but they do have to cover the insect’s body, where they simply coat the exoskeleton (the equivalent of our skin) and smother the insect. It’s extremely effective as long as contact is made with the insect, so spraying has to be done carefully, lightly coating the entire plant.

Keep in mind that this works on contact and there is no residual effect, so that any bug missed is a bug that can still chew, suck and reproduce. For this reason the sprays should be done twice, and if you have scale or mites maybe even three times at the label-recommended intervals. It’s easy to do outdoors with a hand sprayer, starting from the bottom of the plant and working up, remembering to get the undersides of the foliage as well as the bark and stems. And while it’s extremely safe, do read the label to make sure your plant isn’t reactive to the oil. A very few are, most aren’t. I’ve been using Pure Spray Green concentrate for several years, but there are others such as SunSpray.

Don’t use these oil sprays when it’s really hot and don’t leave your plants in the sun after spraying, but other than that they are incredibly safe and effective against houseplant and garden insects.

So get some bargains. Get your houseplants out and cleaned up. Get the plants you’re planning on bringing in ready for their migration and get those houseplants indoors before the night temperatures dip below 50. Keep growing.