September Garden Moves That Stop Spring Pests Before They Start

Cold climate gardeners know September marks a shift in gardening focus: now is the time to sow and plant cool season veggies that can flourish under frost’s threat.

Arugula planted from seed can be easily transplanted when it bolts, while transplanted kale and Swiss chard will continue growing right through fall.

Remove and Dispose of Diseased Plants and Pesty Mulch

As soon as you step outside into your garden or flower beds, everything seems so peaceful and tranquil. Seedlings peeking out from under their soil covers and newly set transplants raising their leaves to absorb sunlight are all picture perfect – until the following morning when holes chewed into leaves appear, as well as plants wilting or yellowing from pest or disease attacks.

Many pests and diseases can be avoided with just a few simple steps. The key is taking a preventive approach to gardening that emphasizes healthy plants by providing rich organic compost, amending soil as needed with other amendments such as lime or compost tea, consistently applying water (plus adding mulch for drainage) as well as regular monitoring to identify problems early.

An annual fall cleanup is essential to controlling vegetable pests like squash bugs and borers, cabbage worms, beetles and cucumber beetles. Pull out spent vegetables, remove weeds and place plant debris on your compost pile or brush recycling bin for pickup by your municipality. If your compost pile is large enough, adding vegetable scraps could help speed up heating up time faster while eliminating unwanted insects from your garden.

Preventing bagworm egg masses from evergreen shrubs from hatching in spring by harvesting them early is also vitally important, as this will eradicate an often overrunning insect problem in such shrubs.

If aphids are attacking your tomatoes or beans, for instance, rather than dousing everything with pesticide, consider supporting the beneficial ladybugs and lacewings which prey upon them instead of spraying all-purpose chemicals to try to eliminate the issue. Eliminating beneficial insects impedes your garden ecosystem’s ability to self-regulate and may cause future recurrence of problems unless careful steps are taken to preserve biodiversity in the ecosystem.

Though these quick wins won’t eliminate all plant disease and insect problems, they will certainly help, particularly in vegetable gardens where fungal pathogens often pose severe threats. Set aside one beautiful fall day to pull your gardening gloves out from storage and incorporate one or more of these simple yet effective strategies into your maintenance routine – be sure to enjoy those delicious veggies!

Disturb the Top Inch of Soil

Though you may wish to till the garden before planting, be careful not to disturb the top inch of soil. That layer holds eggs of many vegetable pests; disturbing this area exposes these eggs and weakens their protective shells; additionally, tilling can expose plant roots to diseases and parasites that might otherwise remain hidden from view.

If your vegetable garden beds haven’t been amended with compost in a while, adding some now could reduce weeds while simultaneously building fertility over the winter.

Perennial flower gardeners typically leave their perennial plants standing through the winter if there have been no disease or insect issues, providing winter beauty, food for birds and pollinators, as well as protection for beneficial insects like ladybugs and lacewings which feed off of aphids.

At the third week of September, it’s time to bring houseplants inside before your furnace kicks on. Start by giving them a thorough cleaning and checking for insect pests; repot potbound specimens into larger containers while they’re still at their most flexible. This task can even be enjoyed outdoors on sunny days as it helps them adjust to lower light levels and humidity indoors.

Set Cover Crops

Fall is the ideal time for sowing cover crops such as clover, rye and oats in garden beds to enrich the soil while deterring pests and aiding with weed control. Seeds for these cover crops can either be broadcasted or drilled; their seeding rate should be increased by 20-50% relative to standard planting rates in order to compensate for poor soil contact, seed predation and residue interference issues.

Add cover crop seeds into the garden as part of an interplanting plan (see companion planting chart) to deter insect pests and increase beneficial insects in your garden. For optimal results, rotate crop families each season so that life cycles of pests don’t get disrupted and new food sources for predatory insects can emerge.

Organic mulch such as grass clippings or last year’s shredded leaves helps protect soil from heavy rainfall, heat and weed growth while suppressing it. But this type of organic mulch does not prevent some insect pests and mites from feeding on crop roots – an alternative would be using frost protection with integrated pest management (IPM), such as using woven row covers which provide frost protection as part of mechanical control (available at garden centers or hardware stores for this purpose) to cover transplants, seedlings or delicate crops like kale and spinach (see Fig 5).

Row covers made of woven materials come in various grades that are designed to repel specific insect pests, like cabbage maggot and boxelder bugs. Stone Barns Center utilizes Proteknet mesh grade while their Horticultural grade protects tomatoes best.

Ideal, rows of vegetables should be covered prior to pest activity increasing in spring. If pests begin laying eggs and hatching in your garden, row cover can be removed in order to protect both vegetable crops as well as breaking up compacted or crusted soils.