Garden Q&A: 'Proven' pest-deterring plants
Question: I've heard that there are certain plants you can plant in your garden to help deter pests. Is there any truth in that, or is it just a bunch of old wives' tales?
Answer: The technique of partnering certain plants with others in hopes of deterring certain pests is a type of companion planting. While many pest-deterring companion planting tactics are not scientifically proven, there's no doubt that some partnerships work, even if they've only been “proven” via hand-me-down knowledge.
While it's true that some companion planting pairings may be more effective than others when it comes to deterring pests, they are worth trying because even if a particular pest-deterring plant partnership doesn't work as well as you'd hoped, it certainly won't cause it any harm. Here are a few of my favorite combinations.
Basil: Among the most popular partnerships, basil and tomatoes go hand in hand — both on the plate and in the garden. Basil is purported to repel whiteflies, spider mites and aphids on tomatoes. Planting basil around young tomato plants also may confuse adult hornworm moths, preventing them from finding the plants and laying their eggs.
Dill: When planted in the squash patch, dill may deter squash bugs. It also may help repel adult cabbageworms when planted amongst cabbage and other cole crops. The heavily scented leaves of dill may repel certain insects, or it may serve to mask the scent of the host plants.
Nasturtiums: Success is found by many gardeners when planting nasturtiums among cucumber vines. They are reported to repel the cucumber beetles that often feed on cucumber leaves and flowers, and transmit bacterial wilt.
Onions: The bold odor of onions may repel pests in and of itself, or perhaps the pests are confused by its ability to mask the fragrance of their preferred host plants. Either way, onions in the cucumber patch may scare off cucumber beetles, and planting them between carrot rows serves to repel adult carrot root maggot flies. Circling a row of onions around tomato plants is said to help repel sap-sucking aphids.
Tansy: Some gardeners use this herb to keep Japanese beetles at bay, planting it among brambles, roses and other plants favored by adult Japanese beetles. Tansy's strong scent is said to either deter them directly or make it difficult for the beetles to hone in on their host plant.
Borage: Used by gardeners for centuries to discourage hornworms on tomatoes and cabbageworms on cole crops, borage is a beautiful addition to the garden. Easily grown from seed, this herb can be readily grown around susceptible plants. It's also great at supporting honeybees and other pollinators.
Castor bean plant: Though it should be grown with care (all parts are extremely poisonous to humans), the castor bean plant is proven to keep moles and voles at bay. Planted around the perimeter of the garden, it keeps voles from moving in. Some commercial mole and vole repellents are made from the castor oil plant because it works so well.
Horticulturist and author Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio. Her website is www.jessicawalliser.com. Send your gardening or landscaping questions to email@example.com or The Good Earth, 503 Martindale St., 3rd Floor, D.L. Clark Building, Pittsburgh, PA 15212.
Show commenting policy
TribLive commenting policy
You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.
We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.
While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.
We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers.
We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.
We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.
We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.
We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.
- UPMC researcher died of acute cyanide poisoning, medical examiner says
- Police still looking for man suspected of robbing 2 people at knifepoint in Ambridge
- No decision yet on charges against elderly driver who struck and killed pregnant woman
- Stakes high as ex-Saints receiver Moore faces his former team
- Witnesses help identify 2nd teen charged in killing Andre Roberts
- Icy roads cause accidents, slow traffic across Western Pa.
- Magicians stage effort to restore Houdini’s grave
- Steelers notebook: Injury to RT Gilbert opens door for Adams to start
- Photo of suspect in Greendale Tavern burglary/fire released
- Boyce Park, Seven Springs, Hidden Valley ski resorts open today
- Washington Co. couple sues Range Resources over drilling, water