Morning Glories (Ipomoea species) are popular vines known for their rapid, twining growth and striking, trumpet-shaped annual blooms. They quickly cover fences, trellises, or arbors, providing dense foliage and color. Gardeners in areas where white-tailed deer are common often worry about damage, making it necessary to understand how deer perceive this plant.
The Resistance Verdict
Morning Glories are not deer-proof, but horticultural experts generally classify them as “seldom severely damaged” on resistance scales. This moderate rating means deer typically avoid them, preferring other, more palatable species. Their resistance is attributed to compounds in the leaves and seeds that are bitter or unappealing to deer.
Deer are opportunistic feeders. While they may pass over Morning Glories for a preferred meal, this plant is not considered reliably high-resistant like some toxic or highly aromatic varieties. The tenderness of young leaves and new shoots makes them a tempting target when other food sources are scarce. Therefore, classifying them as resistant is a statement about preference, not immunity, and damage can still occur.
Factors Influencing Deer Browsing
Inconsistency in resistance ratings stems from environmental pressures and the deer’s dietary needs. Extreme environmental conditions, such as prolonged drought or deep snow cover, reduce natural forage availability. This compels deer to browse plants they would normally ignore, making even the slightly bitter taste of the foliage acceptable.
High deer population density in a localized area also increases the likelihood of browsing, as competition forces animals to expand their diet to less-favored species. Furthermore, the palatability can vary between specific cultivars of Ipomoea, with some varieties possessing softer, more lush foliage that deer find easier to digest. Newly established or heavily fertilized plants are often targeted because their tender, protein-rich growth is especially attractive to a hungry deer.
Protecting Your Morning Glories
Gardeners who are committed to growing Morning Glories must employ consistent preventative measures to discourage browsing. One effective strategy involves physical barriers, such as temporary mesh netting or lightweight fencing, which can be draped over or erected around the vines. While deer can jump high, a simple, four-foot-tall fence may be enough to deter them if they cannot see a clear landing on the other side.
For a less visible option, chemical deterrents applied directly to the foliage can create a taste or scent barrier. Repellents containing putrescent egg solids or capsaicin create a foul taste or smell, teaching the deer to associate the plant with an unpleasant experience. These repellents must be rotated every few weeks to prevent deer from becoming accustomed to a single scent, and they require reapplication after heavy rainfall to maintain effectiveness.
Alternative Deer-Resistant Vines
If protecting Morning Glories proves too challenging due to severe deer pressure, several other climbing vines offer reliable resistance and comparable aesthetic value. Clematis is a popular alternative, with many varieties featuring leathery or toxic foliage that deer reliably avoid. The large, showy blooms of Clematis provide a similar vertical display of color without the same risk of browsing.
Another excellent choice is Trumpet Vine (Campsis radicans), which possesses a sap that is irritating and a generally woody, unpalatable texture. Japanese Honeysuckle (Lonicera japonica) is also highly resistant, partly due to its strong fragrance and the presence of compounds that deter herbivores. These alternatives typically have characteristics like strong odor or tough texture that make them consistently unappealing to deer, offering a more dependable solution for a deer-prone garden.