Despite gardeners’ best efforts, deer do damage landscape plantings. The two questions most frequently asked are: “What can I plant that deer won’t eat?” and “How can I stop deer from browsing on my favorite plants?” Well, if I had the answers, I’d probably become something of a horticultural legend. The simple answers are that there are very few truly deer-proof plants and that, if deer are hungry enough, repellents, scare devices and gadgets, and poorly constructed physical barriers will all fail. Over the years, however, I have developed a repellent program that helps in the fight against deer. With a little diligence and a mix of strategies, you can achieve a “more-than-just-bare-stems” look in your landscape.
Hang sachets filled with Milorganite fertilizer around the area, or apply Milorganite (at half the recommended rate) around emerging bulbs and spring ephemerals. Reapply a month later. Applications of liquid foliar fertilizers/repellents, such as Bobbex, work equally well; just don’t apply them in late summer or fall.
Apply spray repellents like I Must Garden Deer Repellent, an odor-based repellent, every two to four weeks once plants have fully leafed out. Spritz flower buds as they appear with an egg-based product like Deer-Off. Deer-Stopper is a good alternative, or you can make your own repellent. Mix and spray the following ingredients every 10 days: 1 egg, 1/2 cup of whole milk, 1 tablespoon of cooking oil, 1 tablespoon of liquid soap, and 1 gallon of water.
Continue your summer program. Evaluate environmental and biological factors (like the abundance of food sources or the increase in deer numbers) to determine if you should rely on repellents or physical barriers, like fencing or burlap wraps, for the winter months.
Apply a blood-derived spray repellent like Plantskydd during the dormant season (once in November and again in January). Odor- or taste-based repellents can be less effective during cold temperatures. Repellents containing thiram, like Bonide Deer and Rabbit Repellent, will also work; just be sure to add an adhesive like Vapor Gard, because thiram does not withstand weather well.