A problem arising from so-called monoculture (growing a single crop in the same soil year after year) concerns the use of chemical sprays. For years, because of the general gardening practices I employ, I have had no problem with slugs, whitefl ies, or other pests. If I have the odd aphid, I spray successfully using strong herbal teas or a minute dilution of lavender and other essential oils in water. In so doing, I use something the insects fi nd off-putting to deter them. Another method, called companion planting, uses plant chemistry to keep pests at bay. For example, wormwood will produce a toxic chemistry that is effective at keeping invasive plants such as nettles away from desired plants; this practice of using the natural relationships between certain plants has often been applied to forest gardening. The idea of using essential oils and toxic plant chemistry is now being researched
and is becoming more accepted, while the even more desirable technique of always keeping a balance is being rediscovered by farmers and gardeners. A few farmers now plant strips of wildfl owers around fi elds of sweet corn or, in some cases, between batches of sweet corn and other vegetables. In time, perhaps, more trees will creep into the picture, but for now, the presence of a few more wildfl owers and grasses has certainly been found to help maintain the balance between crops and their plant celebrating nature’s alchemy and fragrance 17 and insect predators and parasites. Even Britain’s largest producer of chemical insecticides and fertilizers, ICI, has said that all gardens should have a small quantity of wild plant species growing near cultivated ornamental plants, pointing out that these plants assist friendly insects.
Lacewings and hoverfl ies, for example, lay their eggs on some weeds, and both destroy aphids. That’s quite a quantum leap for a fi rm like ICI, but we need more leaps from them in many more positive directions. Dr. Francis Brinker of the Eclectic Institute in Arizona tells us that certain chemicals in the prickly ash (Zanthoxylum species) act on housefl ies, mosquito larvae, ticks, and several leaf-eating insects, as well as being an ovicide for body lice and toxic to yellow mealworms. There is a great deal of research being carried out into natural insecticides. For instance, where eucalyptus grows, not a single mosquito is to be seen! Agricultural chemicals may be a problem for industrialized nations, but they have had even more serious consequences in developing economies. A ten-million-strong peasants’ revolt in 1994 in India tried to reverse some of the worst aspects of the GATT international trade regulations.