At one time or another, most gardeners have to spray plants to protect them against disease, insects and physiological contaminants. We spray with hand-pump sprayers, hose-end sprayers, and we have come to rely on sprinkling cans every now and then. If there be a problem, it’s how we spray, when we do, and the products we use, not to mention that many gardeners never read labels anymore. This data sheet is written as a basic guide for spraying, and should correct many of the problems that have led to the demise of plants over the years.

* Don’t spray unless a problem needs to be controlled, a problem that threatens the plant’s survival.

* If you can’t identify a problem, don’t spray. Take a sample (leaf, branch, etc.) to a quality nursery and ask help from the nursery manager. If you garden where there is a Cooperative Extension Service office, go there first for answers.

* Before you decide to spray, ask yourself if the product you are about to use is labeled for the problem in the first place. Insecticides only control insects. Fungicides control disease. Herbicides are used for weed control.

* If a plant seems to have had the same disease problem year-to-year, the plant will probably experience the same disease problem this year. The best way of preventing the problem is to clean up the soil, raking up as much debris and organic matter on the soil as possible. Microscopic bits and pieces of organic matter (pieces of leaves) often work their way into the mulch. For this reason, remove the mulch and apply it where it won’t contaminate other plants. Replace it with chunky mulch which repels water.

* Always check the weather forecast before you spray. You want no precipitation for at least 12 hours, and no racy winds to dry the product on the plant.

* Buy only the volume of product you expect to use in the course of the growing season.

* Ready-to-use (RTU) products generally have a shelf-life ot two years, so it makes sense to buy small containers to eliminate chances of surplus pesticides afterward.

* Most liquid pesticides retain their capability for four to seven years, providing they are stored indoors for the winter and not allowed to freeze.

* Powdered garden products are weakened by exposure to humidity, therefore these products should be stored in sealed plastic bags to exclude humidity.

* Estimate how much solution you will need, then mix only that much so there is no surplus to pollute the garden when you are through. To do this, you’ve got to read the label first, then cut back on the mix if need be.

* Metal spray tanks corrode. Pesticides often cause metal tanks to corrode and rust. The best advice is to buy and use plastic tank sprayers.

* If you use hose-end sprayers, reserve one sprayer exclusively for weed killers, another sprayer for everything else (fungicides, insecticides, etc.).

* Avoid mixing disparate products (such as insecticide with a fungicide) since results could provide fatal for the plant to be sprayed.

* Wash and rinse hand-pump sprayers and hose-end sprayers immediately after using.

* Mix pesticides moments before you spray, not mixing one day so you can spray the next.

* Keep all materials in their original containers. With powdered products, place the bag in a clear plastic bag (zip-lock or secured otherwise).

* Store pesticides out of the reach of children.

* Pesticides don’t work with lightning speed (like turning the room light off). Pesticides work, but they need time and patience if they are to solve a problem.

* Try alternative controls first, then check plants a few days later to see if the problem has been stopped. If the problem seems to continue, use the pesticide labeled for the problem.

* Damaged leaves and needles will not return to prior health. Spotted leaves will keep their spots
indefinitely.

* Damaged leaves should be removed (pinched or pruned) since they will not recover.

* Prune blighted foliage promptly. Discard it right away before it falls to the ground and could continue to re-infect the plant.

* When you spray is critical (even with organic materials) because control usually depends on absorption (uptake) of the product.

* Garden products (fungicides, herbicides, insecticides) should be applied as directed by the label.

* Insecticides are defined as working on “contact” or systemically in a plant. Contact insecticides should be sprayed liberally in early-to-mid morning so they reach the very insects you are trying to control. Such products only work when they come in contact with insects. When using a systemic insecticide, spray plant leaves or needles in the evening as long as no overnight rain is forecast. Maximum absorption of the bug-killer happens overnight as long as the leaves stay wet. When leaves dry the next morning, the systemic insecticide is distributed throughout the plant, killing leaf-feeding insects in the process.

* Garden products will work longer if we add “spreader-stickers” or “surfactants” before we spray.

* Do not apply the same product consecutively to control a problem. Having sprayed once, use an alternate product the next time to avoid chances of a “kickback” that perpetuates the problem.

* Most disease-control products offer exceptional control when a second fungicide is added to the spray. When adding the second fungicide, less product is always used.

* When discarding liquid pesticide containers, triple rinse containers, then dispose at a recycling center.