Indoor plants sickly? Stem-sucking insects could be culprit

Written by Jennie Hagen March 15, 2011 02:56 pm

If you started with the low-level fertilizer for your indoor plants about a month ago, now is the time to increase the fertilizer to full strength. Indoor plants should be putting on new growth as a result of the increased light they are naturally receiving and that earlier shot of fertilizer.

Four of my cactus are blooming as they would in their native habitat, late winter or early spring. I fertilize my cactus near the end of winter with one-quarter strength cactus fertilizer, then increase it to half strength a month later.

If you notice some of your indoor plants just don’t seem to be thriving or you are getting too many yellowed leaves, look closely for minute webs, a sure sign of spider mites.

For larger-leaved plants, a shower in the tub once a month is an excellent remedy for getting rid of spider mites as they like stressed and dry conditions. For smaller plants, a regular misting once weekly will usually be sufficient to keep them at bay.

Look for other stem-sucking insects such as scales. They can usually be removed or destroyed, if the infestation is light, by a Q-tip soaked in alcohol. Vigilance is necessary to keep your indoor plants healthy and pest-free.

The retail stores in our areas are loading up on spring bulbs, trees, fruit and vegetable starts. A small amount of time spent inspecting each of these prior to purchase can keep you from bringing home something less than desirable, or spending on something you regret. Here are a few timely tips for spring shopping.

If purchasing bagged plants, check for new growth. Is the growth already pushing the inside top of the bag, is it bent or broken? Is any mold noticeable on the inside of the bag? If the label says there are two inside, are there really two? If there is new root growth, is there mold adhering to the roots? Mold inside bags does not mean you won’t have a good plant, but it does mean that extra care will be necessary to ensure a healthy plant is the outcome.

You will need to wash the molded area prior to planting, and using a weak vinegar-water solution as a spray on the mold can inhibit future mold growth. Use 1/4 cup vinegar to four cups water. You may also make this mixture in a bucket, using the correct proportions, and dip the plants in it prior to placing them in the ground.

For commonly grafted plants, such as roses and some fruit or flowering trees, prior to purchase is when to inspect the graft joint. Is it well healed, with no cracks or weak spots visible? In all of our region of Northeast Oregon, roses that are grafted must be planted deep enough to ensure the graft joint can be safely mulched prior to winter. A grafted rose that is winter-killed to the graft joint may grow the following season, but the new growth will be from the root stock, not the upper part you thought you purchased!

Other grafted plants also need the close inspection of graft joints to ensure a healthy plant is going home with you.

I’ll be visiting the nurseries in our area again this spring and will bring you the latest information and specialties each has to offer. One advantage local nurseries have for buyers is an increased opportunity available to ask questions and special order plants if available.

If you are new to gardening, don’t be afraid to give it a try. Now is the best time to learn the skills needed to be successful, and we all know that homegrown fruits and vegetables are the best.

Until next time, let’s go dig in the dirt!


Jennie Lu Hagen is a La Grande gardener.