Fall Garden Clean-up Reduces Next Season’s Pests
Fall clean up plays an important role in a healthy garden and should be addressed from September to early November. Addressing pest issues in the fall, when insects are less active, can cut back on problems the following year.
At the end of the summer months when colder weather approaches, insects are faced with the option of going to warmer climates or staying tucked away until spring arrives. The majority of insects will stick out the cold months by entering diapause, a phase of life that slows down development and allows for continued life at a much slower rate, often in the pupae stage. Knowing when and where an insect enters diapause will help you find and remove potentially harmful insects before they find your favorite garden plants next year.
Ground cover, leaves, bark, twigs, and any sort of organic material, including this year’s plantings, can be an overwintering place for insects. It is important to remove dead plant material and cut back perennials with a reputation for pest issues.
The majority of insects who burrow into the soil to overwinter can be found in the top few inches. Once the garden is cleaned up, turning the soil will help bring these pupae to the surface where they are likely to fall victim to both biotic and abiotic factors such as predator insects and cold temperatures.
Another step to kill any potential pests is to apply nematodes after turning the soil. There are different nematodes specific to each pest, so correctly identifying the insect at hand is important. Nematodes are commercially available through companies that include Arbico Organics, Bug Logical, and Planet Natural. Once nematodes are applied, a layer of mulch can be applied to further reduce the chance of insects either burrowing into the soil or exiting, retain moisture for nematodes to work properly, and promote healthy microorganisms. To make sure you correctly identify the pest, you can take its picture and send it to to the Dr. Phipps’ Greenline email (greenline[at]phipps.conservatory.org) or calling (412) 665-2364. Phipps Master Gardeners volunteer to help sole your home gardening questions.
Fall pest control methods such as these take advantage of insects’ life cycle to give your garden an advantage through the next growing season.