Worms are the larval stages of butterflies and moths. They have voracious appetites and cause damage in the garden by feeding on the foliage, flowers and fruit of desirable plants. Some large worms, such as the tomato hornworm are large and few in number and can be picked off plants by hand. Other worms, such as the cabbage looper and imported cabbage worm are small and numerous, making control by spraying necessary. Fortunately, there is an organic solution widely available known as Spinosad. It is derived from the naturally occurring Saccharopolyspora spinosa bacterium, and is safe to use in vegetable and flower gardens.
Prepare to spray the garden in the late afternoon after the bees have finished working and the worms are the most active. Measure the required amount of Spinosad into your garden sprayer according to the size of your sprayer. Follow the directions closely on the label. Using too much of the product is not only a waste of money, it can affect the taste of your vegetables.
Add water to the sprayer at a high enough flow to mix the Spinosad and water together. Fill the sprayer to the correct level and screw on the garden sprayer cap firmly.
Spray all plants affected by the worms and any peripheral plants where the worms may be doing damage you cannot see. Spinosad must be ingested to kill the worms, so good coverage is necessary. Spray the underside of the leaves and inside any leaf or flower clusters. Spray cabbage, broccoli, cauliflower and other plants with overlapping leaf structures well, soaking the plants until the Spinosad and water mixture runs off the plant.
Treat areas you may have missed or show ongoing damage over the next several days. Spinosad remains active in the garden for four weeks, but if the infestation is particularly bad, another application may be necessary before the four-week period ends.