 Varmints Sometimes it seems as if every plant in the garden is afflicted by its own separate pest - tussock moth caterpillars for the camellias, hornworms for the citron, aphids for the roses, scale insects for the crepe myrtle, and on and on - wreaking havoc with disheartening speed. Most gardening books recommend the use of pesticides, but we own a cat and, along with the toads, snakes, frogs, lizards, and beneficial insects that live in the garden, all sorts of birds visit the yard we don't want to be spraying poison indiscriminately (besides,many pests are now said to be resistant to commonly-used pesticides). We've tried various "organic" approaches, with little success, and are still looking for less destructive, more selective ways of dealing with pests.Healthy plants are more easily able to withstand predators. Until we nursed our camellias back to health, for example, hordes of ravenous tussock moth caterpillars (which are poisonous and cannot easily be picked off by hand as with hornworms or Japanese beetles) attacked every year. The plums and persimmons also have fewer caterpillars now that they are healthier. Exotic species unsuited to local conditions are also be prone to attack by pests, so we try to stick with plants suited to our area. Aphids and rose slugs on the rambling and climbing roses are a continuing challenge. New shoots are swarmed by aphids and later little green caterpillars that reduce the bushes to bare twigs overnight. We've tried "natural" approaches with no success. Trimming the affected branches works temporarily, but is only a stopgap measure (and also reduces the number of flowers). Bacillus thuringiensis, BT, is one suggested organic caterpillar control that we plan to try. Garden books describe it as a natural bacteria that breaks down rapidly and does not have the harmful side effects of chemical pesticides.  A warm, wet spring provides the perfect conditions for millipedes. We probably also inadvertently contributed to this problem by spreading compost and manure around the garden, improving the soil, but at the same time creating the perfect environment for millipedes. About the only way to fight these pests is to keep the garden free of rotting leaves and other debris. This is also true for slugs, pill bugs, and snails.Azaleas are regularly attacked by spider mites. Since these pests don't like moisture, they can be controlled by spraying the infected bushes' leaves with the hose, making sure to blast the underside, where the mites congregate. Plum trees appeal to Japanese beetles, which leave the leaves looking like Swiss cheese. One way of controlling beetles, besides catching them (something our cat loves to do), is to destroy the larvae, which live just underground. Old as she is, our cat does a good job catching mice and is probably helped by the snakes. Moles are more of an irritation than anything else since we don't have a lawn. On the plus side, the garden hums with bees and wasps, which prey on caterpillars and other destructive pests. Ladybugs help control aphids and other pests. Bats, birds, lizards, and spiders also pitch in. Besides being fun to watch, dragonflies help reduce the mosquito population in the garden. Praying mantises are also predators, but they prey on both harmful and beneficial insects. Other than choosing healthy new plants and maintaining the health of existing plants, keeping the garden clean is one of the best deterrents. Pests overwinter under fallen leaves and other debris so thorough cleanups in fall go a long way toward reducing the pest population. |