Some pests, such as the tomato homworm, can be picked off by hand; some, such as spider mites, can be washed off with a strong jet of water from the hose. A word on systemics: these are pesticides and fungicides which are taken up into the plant’s system, rendering the plant poisonous to all who would chew upon it (please note, parents whose small children have indiscriminate appetites).
Systemics come in granules which you scratch into the ground under the plant, liquid you paint on the trunks of trees, and spray. These systemics are strongly advocated by many experts for use on deciduous trees and roses especially, and I must confess that I use a systemic spray containing a fungicide on my roses. Many gardeners have complained, however, that they have killed young trees by painting bands of systemics on the trunks, so read the entire label directions, taking careful note of special precautions recommended.
Whether you decide to use a systemic or any other form of chemical poisoning against insect pests, do read directions very carefully. And if spraying is just not your thing at all, then choose plant varieties that are relatively pest-free. Last year, completely fed up with the pest problem on my currants, I dug them up. Reluctant as I was to give them up. I just wasn’t willing to wield a sprayer over them the whole season long.
If you are choosing an all-purpose garden spray, try to choose one that has the least toxicity as possible. Malathion and nicotine sulphate are considered relatively safe, if they are available in your area, though one should note that each can be highly dangerous to man if use without care. Ordinary sulfur can be used against mildew. When spraying, cover yourself up well so a minimum of skin surface is open to absorb any spray that may drift back to you.
Toss pride to the winds and don rubber gloves, a long shirt and an old diaper wrapped about the nose and mouth. Weeds are another problem most gardeners would like to deal with chemically, as weeding is not most people’s idea of recreation. In lawns, 2-4-D is commonly used for dandelions but it will not kill off more difficult weeds like chickweed or ground ivy. For this you need 2-4-D with a chemical addition especially for these tough weeds. The labels state which will kill off what weeds.
These chemicals come in various forms: spray, weed bar and spot killers in aerosol or long, hollow sticks which administer the chemical to individual plants. I’m opposed to using the spray form because the tiniest drift of 2-4-D will kill off your neighbors ornamentals or tomato plants, or your own for that matter.
The wax-impregnated weed bar is good for the more seriously infected lawns but if the weeds aren’t too numerous, I’ve found the most satisfactory method in the cane-type of applicator in which you drop a tablet into the water in the container. In the perennial border and vegetable garden, the trick is to not let any weeds go to seed for a season or two. After that, your job is simple.
There are on the market pre-emergent “weed preventers” which are applied between plants to kill off any weed seeds that may be lurking in the soil. Read label directions and note precautions carefully. Last of all, there are chemicals which kill all plant life, rendering the soil sterile. These are used in such places as driveways. I always use either borax or salt, whichever is cheaper. Borax lasts in the soil longer than salt but both I feel are preferable to other chemicals sold for this purpose. I just sprinkle the salt or borax on the driveway and water it in.