Experts discuss how to keep critters away, gardens in mint condition

By: Sherri Kolade | Farmington Press | Published August 19, 2015


METRO DETROIT — Farmington Hills resident Chris Britts’ green thumb blossomed as a child growing up in Albuquerque, New Mexico, with her mother in their garden at home.

“I did things with her, and every place we’ve lived, I’ve worked on plants one way or another,” the 71-year-old said, adding that her English grandfather instilled a love of gardening in her mother.

The longtime Farmington Hills resident said that her love of gardening has come with highs and lows, such as nature’s pets munching on her plants.

“I have anything from deer on down,” Britts said. “As far as mammals go, deer and groundhogs are some of the biggest destroyers.”

Britts is in a predicament that many find themselves in: fighting off garden critters.

Charlene Molnar, a Michigan State University Extension horticulture advisor, has some solutions.

She said there are three ways to deal with critters: tolerate, discourage, remove.

Tolerate by planting things critters would not eat.

“Try not to provide a habitat for that animal — places where it could burrow,” she said. “You have to have walls under sheds. Don’t put out bird feeders.”

Along with repellants, she suggested removal, although relocating animals into another habitat could upset nature’s balance.

“You are just giving somebody else your problem,” she said.

The three most common animals that MSU Extension receives calls about are deer, groundhogs and skunks.

“We get calls on everything,” Molnar said. “Following that would be rabbits, squirrels, chipmunks, snakes.”

Molnar said the state deer herd is “exploding” as its habitat declines.

“They are going to invade different areas,” she said, adding that deterrents could include plant-applied smell and taste deterrents, and landscape and electric fencing.

Outside of fencing, groundhogs must be trapped, while rabbits and deer need to be trapped or repelled.

Molnar said there are “tons” of products on the market that do the job, such as Plant Skid, a liquid fence spray.

Others include sprays made out of hot pepper, putrefied eggs, garlic and even dried blood.

“Reapply with frequency,” she said. “The label is the law.”

She added that there is no proven data that the products will work 100 percent of the time.

Trevor Johnson, resident farmer at Henry Ford West Bloomfield Hospital, who helps maintain a 1,500-square-foot hydroponic greenhouse that provides greens to patients, said the universal approach is to observe your garden.

“Set some time aside at dusk and at dawn, when a lot of the four-legged pests are active, and observe where they are moving around your landscape, where they are going for food, (where they are) avoiding. See if they have difficulty getting over an obstacle, and use that information to help design your garden, or figure out some way you can keep the pests away.”

Britts tried it all. She hung clumps of human hair, which retains a person’s scent, and bars of deodorant soap near her plants to discourage deer dining.

“Soon as they realize it is not going to hurt them, they ignore it,” Britts said.

Britts, who is surrounded by woods and an acre of wetlands, said she is moving toward growing native plants, which don’t attract as many critters.

“I think the deer will eat just about anything, but the closer you get to what is normal around them, the less appealing it is,” she said. “They really like the nice hybrid salad bar.”

Some plants frequently damaged by deer include strawberries, English ivy, tulips, clematis, lettuce, spinach and balsam fir, according to MSU Extension.

Johnson said Henry Ford West Bloomfield Hospital’s greenhouse uses an organic method of biological control, using insects to eat other insects.

“We release things like ladybugs, minute pirate bugs, praying mantis and spider mite predators to keep balance,” he said. “We can inhabit our garden with good insects that will keep the bad ones away, like aphids, spider mites, mealybugs, scale insects.”

In a typical week, 3,000 ladybugs are released into the garden.

Johnson added that if that doesn’t work, soap byproducts —  a natural insecticide such as potassium salts of fatty acids — are where it is at.

Gardeners could also use Dr. Bronner’s soaps and one to three tablespoons per gallon of water as a spray for light to heavy infestations. Johnson said spray mixtures of garlic, hot pepper flakes, soap and water might also help.

“There are many different formulas of this,” he said. “Spray it on part of the plant the animal is eating. ... After you harvest it, wash it off, and that will remove the garlic and hot pepper (taste).”

Johnson said the animals learn from experience that the taste is not pleasant and they leave the plant alone.

“You have to be pretty persistent with it. You have to reapply so often,” he added.

Johnson uses Plantskydd Deer Repellent, which is sprayed on the border of where any deer might walk onto the property.

The spray contains hormones or pheromones warning other critters that a predator is nearby.

“They want to go in the opposite direction,” Johnson said. “It sticks to the ground, and in six to eight months ... you can do a second application.”

Britts said she used the spray with some success.

“It is the only thing that really seems to work,” she said, although she said that the smell is bad.

Johnson said if gardeners use simple techniques, they will succeed in keeping four-legged critters out, but humans, not so much.

“You’ll be able to keep all but the two-legged predators out of your garden,” he said, chuckling.

For more information, call MSU Extension’s hotline for garden help at (888) 678-3464 or Henry Ford West Bloomfield Hospital at (248) 325-2060.