Ask An Expert: Niki Jabbour
Curb critters from taking over your garden with expert pest-prevention advice from award-winning author Niki Jabbour.
Are gophers destroying your squash year after year? Do deer break into your garden daily? Having trouble protecting your precious plants from bugs and pests?
We asked our Short Storey Newsletter readers for questions about all things gardening, then tapped master gardener and award-winning author of Growing Under Cover, Niki Jabbour’s Veggie Garden Remix, The Year-Round Vegetable Gardener, and Groundbreaking Food Gardens Niki Jabbour for answers.
Roy C. asks: Gophers! What can I do about these darn gophers that keep destroying my crops? Last year, they wiped out my potatoes, zucchini, and squash. The neighbor’s cat caught a few (and kindly left parts of them at our back door as proof) but short of adopting an army of cats or digging up the entire backyard to install gopher cages, what are my options? Is there a plant or mushroom or something I can grow to deter them?
Ambre P. asks: I live at 5000ft in the high Arizona desert where it gets to the 20-30’s in the winter and 100-109 in the summer with lots of wind. I live within a block of a rural grade school and everyone in my area seems to have the same problem. Rodents, desert rats, and their predators (javelina, snakes, coyotes) get through conventional protection methods (buried fencing, small mesh fencing, repellents, etc.) and destroy gardens. Also, while I love my compost, it seems to draw rodents and rats—which are already drawn to the area because of the school—who eat everything. It’s already hard to grow plants here with temps, low humidity, winds, and wildlife. Any ideas on how to fend the rodents off?
Niki answers: I learned early on that there is no such thing as a pest-free vegetable garden. My earliest memories of battling pests weren’t dealing with insect pests like squash bugs or cucumber beetles, but the larger critters like the deer that ravaged my crops each night. They would mow down the bush beans, nibble the carrot tops, and take a single bite out of ripening cucumbers and tomatoes. Frustrating!
When I moved to my current house, I immediately broke ground on a new vegetable garden. It probably wasn’t a great sign that there were several bunnies hopping around the backyard as I started to build my beds. Or a group of five deer wandering in the woods behind the property. Over the years I’ve learned several strategies to help prevent or reduce animal damage to my crops, but I would first suggest identifying the creatures that are targeting your garden. This helps you decide which tactics to take to boost your success.
A barrier is typically the most effective pest-prevention strategy, but if a fence isn’t possible there are other options for gardeners. My neighbors found success keeping deer out of their backyard thanks to their large dogs. Another gardener I know uses a fragrant lavender hedge around her small food garden to deter pests like deer, rabbits, and groundhogs. I’ve found that using multiple strategies – a barrier combined with scented plants, for example – can help you be more successful.
In my most recent book, Growing Under Cover, I talk about using garden covers like row covers, insect netting, bird netting, deer fencing, chicken wire, and other materials to prevent damage to vegetables. You can float many of these on hoops to create quick DIY protective mini tunnels or use them to surround your beds. Let’s dive into some of the more common strategies gardeners can use to protect plants.
Clean up
The first step in reducing animals is to make the vegetable garden and the area surrounding it less attractive by eliminating hiding or nesting spots like tall grass or areas with dense cover. Also, keep bird feeders away from your food garden as they can attract animals. If you have a compost bin by your vegetable garden, make sure to bury fresh food scraps in the middle of the pile or cover them with a layer of straw or leaves.
Repellent plants and sprays
Strongly scented plants like the above-mentioned lavender as well as basil, bee balm, onions, dill, garlic, catmint, rosemary, and marigolds are less favored by animals like gophers and deer. Planting them around susceptible crops like tomatoes, beans, and cucumbers may help deter pests. Are they 100% effective? Probably not, but they are a layer of protection. I have clumps of lavender, ornamental onions, and catmint surrounding my raised bed garden. They look great, attract pollinators, and maybe even deter animals.
You’ve probably also heard that using scented soaps or dryer sheets can prevent animal pests but I find it best to stick to scented plants or deterrent sprays. Soaps quickly turn mushy and make a slimy mess and dryer sheets contain a lot of chemicals I don’t want introduced into my soil.
Deterrent sprays are available from garden centers. They often contain ingredients like garlic, hot pepper, cinnamon oil, peppermint oil, fish oil, eggs, and so on. Not the most palatable-sounding mixture and also not something you want to spray directly on vegetables. These sprays are typically recommended for ornamental plants. That said, I have used them to protect my food garden by spraying strips of fabric and tying them to stakes around the outside of the garden. It smelled terrible and lingered for days, but it did seem to have some effectiveness against deer. Re-spray the fabric strips after a rain.
Cayenne pepper
A lot of gardeners tell me they swear by cayenne pepper for pests like groundhogs, gophers, rodents, and squirrels. They sprinkle it around crops or, in the case of groundhogs and gophers, directly in the holes. You’ll need to reapply after a rain. Similarly, soaking cotton balls in peppermint oil and placing them in gopher holes can repel these rodents from your yard.
Barriers and fencing
There are large and small barriers you can buy or DIY for excluding animals. Small examples include chicken wire or willow cloches for sheltering seedlings from hungry wildlife, or mini hoop tunnels topped with deer netting. Gardeners can also use chicken wire, galvanized gopher mesh, or hardware cloth beneath raised vegetable or flower beds to prevent gophers and other rodents from sneaking into the garden.
Fencing is among the most effective barriers for reducing damage from deer but comes with a higher cost. I used to use 7 foot by 100 foot lengths of deer netting mounted to wooden posts as a fence. It was more cost effective than a tall wooden or chain link fence, but there were times the deer would leap over or run through it, tearing the plastic mesh. A decade ago I invested in an electric fence, mounting the wires to those same wooden posts. I use four tiers of wires and this fence has been very effective keeping the deer out of my garden.
After a few years I noticed damage to the crops inside the fence. I initially blamed deer, but soon spotted two groundhogs inside the garden. I then added a length of 3-foot tall chicken wire to the perimeter of the garden. That has kept the groundhogs out. To be even more effective at keeping digging animals like groundhogs and rabbits out of your garden, use 4-foot tall chicken wire fencing and bury the bottom 12 inches under the soil to prevent burrowing.
Loud noises
Using a loud radio or a motion-activated alarm certainly can startle animals – as well as gardeners – but are they effective? Noisy tactics tend to work short-term, but animals like deer eventually realize there is no danger and return. Plus, your neighbors probably won’t appreciate a constant loud radio or intermittent alarm going off day and night.
I’m often asked about whether ultrasonic devices, marketed for animal control, are effective at driving away animals. My short answer: no. These pricy devices are often sold for pest prevention, but several university studies have shown they do not repel pests. Don’t waste your money.
Article text © Niki Jabbour. Please note questions from readers have been edited for length and clarity.