Deer damage is a common issue for gardeners, as these large animals thrive in many rural and suburban environments and are often drawn to the lush and tasty plants that fill our gardens. Deer can cause considerable damage to flowers and vegetables in home gardens. Deer can also cause damage to woody plants, especially in fall and winter. When damage becomes unacceptable, control measures are in order.
Plant Selection & Placement | Fencing | Repellents | Scare Devices | Protection Over Winter | Antler Rubbing | Managing Damage Once it Occurs | More Information
Plant Selection and Placement
Home gardeners may be able to avoid some deer damage with careful plant selection. Plant species that will be damaged by deer can vary widely based on location, deer population, and other food sources available. Nearly any plant (including those commonly listed as rarely damage) can be browsed on by deer, but some species are much more likely to be damaged than others. More information can be found in this article: Susceptibility of Plants to Deer Damage.
Deer are highly habitual. Identify areas they frequent and avoid planting their favorites or highly valued plants in these areas. Alternatively, plant deer favorites, like hosta or daylily, in areas that are easy to protect or less likely to be visited, such as near the home or in a place with a lot of activity. Sacrificial plantings can also be established in areas more distant from the garden to draw deer away from more prized plantings.
Fencing
Exclusion with fencing and other materials is the most effective way to prevent deer damage on plants. However, building fences can be expensive and exclusion devices can distract from the beauty of the garden.
Two types of fences can potentially be constructed: passive or active. Passive fences simply act as barriers. They must be at least 8 feet tall to prevent deer from leaping over and extend all the way to ground to prevent them from ducking underneath. A wide variety of materials can be used but woven wire fencing is one of the most common and reliable. Netting can also be used as it is typically less expensive and less visually obtrusive but is more prone to damage.
Fencing can also be place around favorite plants or temporarily placed around plants when they are more prone to damage, such as when in fruit or when the new growth first emerges in the spring. Cylinders of fencing around individual plants up to at least six feet or with a "lid" on them for smaller plants can be effective. Be sure the fencing is far enough from the foliage to prevent a tongue from grabbing it!
While not one hundred percent effective, fences shorter than 8 feet can be effective. A six foot privacy fence, for example, is not likely to jumped over as the deer cannot see where to land on the other side. Similarly a small area (less than 10x10 feet) with a six foot fence around it is not likely to be hurdled as the deer do not see enough room to land inside.
Active fences use electricity to deter deer from entering. They require less infrastructure (and therefore may be cheaper to build) but require more attention. Several strands of electrified fence and be installed temporarily (such as around sweet corn when it is ripening) or more permanently. Electrified fences work to scare deer when they touch them so they must be visible and the deer must learn not to touch them to be effective. Electrified poly tape (ribbon-style) fences work particularly well. It should be baited with peanut butter to teach deer to avoid them.
More detailed information on fence specifications and styles can be found in this article: White-tailed Deer: Damage Management.
Repellents
Feeding from deer can be discouraged by repellents. Although repellents are rarely as effective as you would hope!
Taste repellents, such as hot sauce and thiram, make plants distasteful. These must be applied directly to the plants that need protection. Light browsing may be seen as the deer have to learn the plants have a bad taste. They will need to be reapplied often to maintain effectiveness including after heavy rains, irrigation, heavy dew, or to new growth as the plant grows. Additionally, deer quickly become used to the poor taste and may ignore it. Taste repellents cannot be used on edible crops (because we don't want them to taste bad!).
Area (odor) repellents can sometimes be more economical as they are applied to the perimeter of the garden to deter deer from entering rather than to all the plants within the garden. Area repellents include rotten eggs, predator urine, blood meal, moth balls, human hair, and bar soap, among others. There are many examples of odor repellents and every garden blogger and garden tip book includes their own "tried-and-true" recipe for a deer repellent. Unfortunately, these repellents are not always effective. Deer quickly become accustomed to the disagreeable odor. Alternating between different types or scents can help extend the time it takes for the deer to become accustomed. As with other repellents they need to be reapplied often to maintain effectiveness including after heavy rains, irrigation, and heavy dew.
In many cases repellents are best used in conjunction with other tactics since they are rarely adequate on their own.
Scare Devices
Scare devices include devices that make loud noises like exploders (that make a loud noise at regular intervals), gunfire, or fireworks. Dogs and motion sensors attached to flood light or water sprinklers can also scare deer away.
In many cases, scare devices only provide temporary relief (typically a few weeks). Deer quickly get used to the sound or intervals of noise makers and start to ignore them. They can also learn the boundaries of motion sensors and dogs and continue to browse just outside these areas and in some cases just ignore them altogether.
As deer are very habitual, scare devices can be used to break patterns or disrupt travel paths. If the deer change their nightly rounds to not include walking through your back yard, you are less likely to see damage.
Protection Over Winter
Deer may feed on trees and shrubs during winter and severely damage or destroy plants. Damage is most likely to occur when food is scarce during prolonged periods of snow cover. Deer often feed on the foliage on the lower branches of arborvitae, pines, and other evergreens but also feed on other plants, including woody trees and shrubs, especially when food is scarce. Prevention is key to managing this damage.
Learn more in this article: How to Protect Trees and Shrubs from Animal Damage Over Winter.
Antler Rubbing
Deer not only cause damage to the garden by feeding on a wide variety of plants, they can also strip and tear bark from young trees in the early fall through antler rubbing. In fall, bucks rub their antlers on trees to remove the dried velvet from their antlers and to mark their territory. This rubbing removes the thin layer of bark on small trees and can seriously damage or destroy them as it disrupts the water and nutrient-conducting tissues in the tree. Young trees with flexible trunks and thin, smooth bark are most likely to be damaged. Once trees have more corky and thick bark with trunks that are not flexible (usually when they are 3 to 4 inches in diameter or larger), the chance of damage from antler rubbing goes down significantly. Trunk damage typically occurs 1½ to 3½ feet above the ground.
Exclusion is the best way to prevent this damage. The barriers must be in place by mid-August and should be removed in the spring to prevent possible interference with growing trees. One of the easiest and least labor-intensive methods is to drive three or more sturdy metal or wooden stakes around the young tree. The space between the posts should not be more than 18 inches. Tubes, wraps, wire fencing, and wire cylinders can also be placed seasonally around individual trees. The fencing material must be sturdy (such as steel welded wire fencing) and attached to sturdy posts. .
How to Manage Deer Damage If It Occurs
Browsing on Evergreen Trees and Shrubs
Evergreens are regularly damaged by feeding deer over the winter. Arborvitae and yews are most susceptible to browsing by deer in winter.
The extent of damage to the lower portions of the arborvitae will be determined by the presence or absence of buds (growing points). If buds are present, the lower branches will produce new growth in spring. The new growth should be apparent by early summer. The lower portions of the arborvitae will remain bare and likely never develop new growth if no buds are present.
Browsing on Deciduous Trees and Shrubs
On many trees and shrubs, deer will browse branch tips and stems. Heavily damaged trees may need to be replaced, but if only secondary branches are lightly browsed, the tree will recover. Most deciduous shrubs can produce new shoots or suckers at their base. Because of this ability, many severely damaged deciduous shrubs will eventually recover. Several years may be required for some shrubs to fully recover.
Browsing on Perennials, Annuals, and Vegetable Gardens
Herbaceous plants will continue to grow after being fed on by deer. Provided feeding doesn't continue, new foliage will grow to replace what is lost and the plant may look and produce just fine, especially those that saw damage early in the growing season. On most perennials and bulbs, flowers ate will be lost of the season. After browsing some perennials may produce a second flush of flowers (if the deer don't continue to eat them) and others, especially bulbs and other seasonal bloomers like tulips or cardinal flower, will forfeit their blooms for that season.
Damage from Antler Rubbing
The process of rubbing removes bark. If the bark is removed on a large portion of the tree or completely around the trunk, the tree becomes girdled. All growth above the girdled areas will eventually die, and for most home gardeners, replacing the girdled trees is the best course of action. There are no applications that will mitigate the effects of deer damage or save severely damaged trees. Wound dressings, pruning paints, latex paints, wrappings, and other alleged protective barriers do not help.
More Information
- White-Tailed Deer: Damage Management
- Susceptibility of Plants to Deer Damage
- How to Protect Trees and Shrubs from Animal Damage Over Winter
- Internet Center for Wildlife Damage Management: Deer
Photo credits: 1: Dan Sheehan/AdobeStock; 2: Aaron Steil; 3: Aaron Steil; 4: Aaron Steil; 5: Aaron Steil