Horticultural News – When the Garden is Under Attack

This growing season promises to be filled with adventure…and not necessarily of a good kind. On the Gulf Coast, we had a cold winter, at least by our standards, and plants that usually cruise through the winter suffered freeze damage that weakened them, making them more susceptible to insects and disease. Now we are enjoying a warm and very wet spring, creating conditions for lush growth of plants and insects alike. West Texas didn’t have much of a winter at all, and that will lead to legions of insects that overwintered and are ready to get a jump start on eating cherished plants. Wherever you garden in our region, sometimes there will be a virtual plague of, say, white flies or aphids attacking everything in the garden. Is it time to pull out the poison sprays?  Please don’t.

Here is my position on all commercial chemicals in the garden: I don’t like them, and I don’t like to use them. I worry about long-term effects on the soil, about probable runoff getting into the water of our rivers, lakes and oceans, and about the damage to the fauna in my garden. When you spray with poisons, you can end up killing beneficial beetles that live under the bushes, bees that are buzzing around, caterpillars – who knows what all. I know this from firsthand experience: several years ago we had a serious flea infestation thanks to an opossum that had taken up residence under our deck, and we hired a pest control company to treat for fleas. It did rid the yard of fleas, but wound up killing most of our native anole lizards. It was awful; the poor little things lay in the poisoned grass gasping until they succumbed. If the poison was strong enough to kill lizards, it certainly killed plenty of beneficial insects, too. Our ecosystem needs our lizards, and we need insects, for pollinating flowers, aerating the soil, and feeding the birds and other creatures that share our gardens with us.

Plants, especially native plants, have natural defenses to pests and disease, and if you keep your plants healthy, there will be less need to resort to poisonous treatments. If you work on improving the soil in the garden, chances are good that you won’t need to call in the heavy artillery. By working in compost and sand you can condition the soil, improving its texture and drainage, lessen compaction, and promote beneficial microorganisms and earthworms.

All that being said, there are times when it seems like Mother Nature just has it in for us, and an army of insect marauders comes in wave after wave, eating plants and otherwise causing devastation in the garden. When an insect infestation hits, try to get rid of it by using the least damaging approach first. Heavy sprays of water from a hose end nozzle can knock bugs off the plant, and frequent repetition of this tactic can interrupt the life cycle of the insect and end the problem. Next step up would be spraying with insecticidal soap, and if this is repeated once a week, the insects will usually be subdued. Nurseries and hardware stores sell soap sprays, but they are simple to make with this recipe:

HORTICULTURAL OIL SPRAY: 1 Tablespoon vegetable oil, I teaspoon liquid soap, and 2 cups water in a spray bottle. Shake well and spray directly onto the troubled plant. (Use ordinary dish detergent or hand soap, but get the kind without antibacterial agents or hand softeners.) The most poisonous ingredient in this concoction is plain soap, so you can feel very safe using it around your pets and plants.

Spray the tops and undersides of leaves, and try to avoid getting drips on you. It isn’t poison but soap in the eye is never pleasant. To reduce leaf burn, spray in the late afternoon or when the plant is in the shade. Remember that excessive spraying, even with something as benign as soap, can harm beneficial garden creatures like earthworms and bees.

If soap spray didn’t do the job in a couple of applications, and there is still damage being done, try organic remedies, such as citrus oil. Orange oil can be purchased or you can make your own.

Citrus Oil Spray: Chop the peel of one orange (or two lemons) and boil it up with 4 cups of water. Let it steep overnight, then strain out the peels. Use the resulting liquid in a spray bottle to attack pests on your plants. Don’t get it in your eyes because it stings like fury, and since some plants may be sensitive to the citrus oil, test a leaf first. If there is no evidence of damage after a couple of hours, go ahead and treat the plant. It smells great, and is safe enough to drink. You can also add a teaspoon of soap to the bottle to help the oil stick to soft-bodied insects, but then drinking would not be advised. Again, protect your eyes because citrus oil will cause you pain, nothing permanent but very uncomfortable.

This spray proved to be effective when we were hit by a plague of spider mites one summer. Any time the garden suffers from dry conditions, red spider seems to appear. Actually, they are always around, but the effect of their dirty work is more apparent when plants are already stressed. Before I became a rabid convert to native plants, we had an angel trumpet tree in the back garden for about ten years, and that summer it had spider mites so bad that the leaves were limp and grayish. I tried the old wash-‘em- off with water trick, and the only improvement was that I had a CLEAN sickly tree. I moved up to a commercial soap spray and drenched that tree using a hose-end sprayer. In the process of insuring that every square inch of that tree was treated, I thoroughly doused myself – being meticulous about treating the undersides of the leaves left me no alternative but to get up under the tree branches and spray upward. Still, the spider mites persisted, and that’s when I went online and found the citrus spray recipe on a website called www.yougrowgirl.com. There I found several recipes for “insecticides safe enough to eat (if you must)”. It was not my intention to make a snack of it, but considering my experience with the soap spray and the soaking that I got, I knew I would probably wind up wearing it, so sticking with safe products was a good bet. The good news is that the citrus spray knocked the spider mites way back, and an inch of rain soon after the citrus treatment made the cure complete.

As much as it pains me to say it, at times these gentle approaches will not be sufficient to solve the problem of a pest infestation, and the only answer seems to be chemical warfare. If you have a particularly prized specimen in your garden that you absolutely cannot live without, then, of course, you are going to do what you have to do to save it from an insect attack. In that case, please look for an organic pesticide that promises to do as little harm as possible to the environment. I won’t recommend any brands here because I simply don’t use them, but if you do use them, be sparing in the application. You may have noticed that the recipes provided above are in small batches for application in a hand sprayer, not for treating wide swathes of the garden all at once. The best approach, in my opinion, is to treat specific problem areas rather than bombing the whole garden. This will limit the amount of harm done to susceptible fauna. As gardeners, we owe it to future generations to preserve this planet the best way we know how, and limiting the amount of chemicals we spread around is surely a step in the right direction.

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