Garden pests, be gone!

An adult Japanese beetle feasts on foliage.

10 ways to manage unwelcome garden visitors without pesticides

If you have a garden of any shape or size, the odds are good you also have some bothersome garden pests. Yes, aphids and slugs, Japanese beetles and stink bugs (among many other pests!) unfortunately view your beautiful plants as a bountiful buffet upon which to feast. 

That’s the bad news. Here’s the good—because most garden pests have been around for years, gardeners have found some tried-and-true methods to combat them without relying on pesticides. Let’s dig into some of the best ways to manage those unwelcome garden visitors naturally and maintain happy, healthy, beautiful, and productive plants. And remember, the best way to manage pests is to prevent them from infesting your garden in the first place!

Cultivate healthy soil. We’ve said it before, and we’ll say it again—healthy soil makes for healthy plants, and healthy plants are better able to withstand pests and disease. Many local extension offices offer tests that analyze your soil for pH, organic matter, and macronutrients like nitrogen, phosphorus, and potassium. Learn more about soil health from Seed Savers Exchange’s greenhouse coordinator, Kate Rowe, and field technician, Brennan Allsworth, in this video from our 42nd Annual Conference. Access to the all of the conference programming is available here.

Start with healthy plants. Before moving the plants you’ve started (or bought) into your garden, make sure they are healthy. Do they have robust leaves and branches, sturdy stems, and well-established root systems? For added protection against pests, look for varieties that are disease- and insect-resistant. 

Select the optimum spots for your plants. The healthier your plants, the better able they will be to withstand the onslaught of pests and disease. And one way to promote plant health is to place your plants where they will thrive: place plants that need full sun in full-sun areas and place plants that require more water in areas that retain moisture longer. 

Learn the difference between pests and beneficial insects. All gardens draw insects, some helpful and others harmful. Get to know the different insects different plants in your garden attract so you can distinguish which insects to fight and which to cultivate (for example, bees and butterflies). 

Entice birds and beneficial insects. Did you know that birds and many wasps, flies, and beetles eat pests like aphids, stink bugs, and Japanese beetles? Birds love a good bird bath or bird feeder. To attract beneficial insects to your garden, grow flowers that provide nectar and pollen. (Think borage, calendula, coneflower, and marigolds, among others.)

Tomatoes and nasturtiums make a winning combination.

Practice companion planting. Planting select crops close to one another has proven time and again to foil garden pests. Onions, for example, are known to repel many harmful insects, while radishes deter beetles from beans, peas, squash, melons, and cucumbers. Bush beans planted near potatoes will help protect those potatoes against the Colorado potato beetle—found not just in Colorado and not just on potatoes!—while the potatoes, in turn, will keep the bush beans safe from the Mexican bean beetle. Nasturtium flowers not only look enchanting planted with tomatoes but also also serve as a trap crop for aphids that may infect them. Rosemary’s aroma deters bean beetles, cabbage moths, and carrot flies. (Note: There are many winning plant combinations when it comes to pest management; this list is just a start!)

Plant marigolds, nasturtiums, and calendulas. Marigolds attract beneficial insects like lady beetles that in turn prey on insects that can damage crops. Nasturtiums repel whiteflies, squash bugs, aphids, and cabbage loopers. Calendulas work overtime as a “trap crop”—catching aphids and other pests by exuding a sticky, appealing sap.

Invest in floating row cover. Versatile and easy to use, floating row cover lets light in while it keeps out pests like Japanese beetles, potato beetles, cabbage worms, and leaf miners. It also protects your plants from frost and wind. 

Keep your garden free from disease. As already noted, healthy plants better withstand insects that want to wreak havoc in your garden. From sanitizing your garden tools to rotating your garden crops, many common practices can help prevent disease in your garden space. Check out this SSE guide for more tips on keeping your garden disease-free.

Consult your local extension office. Your local extension office has a wealth of information on all things gardening, including pest management. Don’t hesitate to tap into this handy resource!

Sources: UDSA and The Farmers’ Almanac.