Researchers want your homemade deer repellent concoction

Be part of a Connecticut study on home-recipe deer deterrents…

deer pruned lilyOne of the most frustrating aspects of gardening is to have your lovely plants and shrubs and your hard work and hard-earned cash disappear overnight into the belly of one of the estimated 80,000 deer living in Connecticut. This is even more frustrating after spending additional ‘green’ on commercial products purported to deter deer browsing.

Scientists at the Connecticut Agricultural Experiment Station (CAES), in New Haven,  and others have done quite a bit of research on commercial deer repellents (more on this below). Now researchers at CAES are extending their investigations to homemade formulations and they want to hear from you.

Here’s their request:

The Connecticut Agricultural Experiment Station is continuing its research into the effectiveness of repellents to prohibit deer browsing on agricultural crops and homeowners’ landscape plantings and gardens in Connecticut.

Do you have a home-brewed deer repellent you think works well?

We are soliciting unique, effective “home remedy” deer repellents to evaluate alongside commercially available repellents. If your home remedy is selected and you are willing to assist us, we will recreate your home made deer repellent solution and treat test plants in our research plots. We then will evaluate and rate the effectiveness of each of the treatments.

Please follow this link HomeBrewedDeerRepellents to a solicitation survey form. Please fill out the survey as completely as possible, make sure to describe the remedy you use in full detail.

Please feel free to e-mail me with any comments or questions.

Michael Short
Agricultural Research Technician
Dept. of Forestry & Horticulture
The Connecticut Agricultural Experiment Station

The study will run through 2011 and possibly through 2012, but to make the study work CAES researchers need homemade recipes. Over the winter of 2001-2012 they plan to report the findings from the 2011 growing season. If they are able to extend this study into 2012 they will report two-season results over the following winter.

CAES scientists already have data on the efficacy of commercial deer repellents. [Reference: Ward JS, Williams SC, Effectiveness of deer repellents in Connecticut, Human-Wildlife Interactions 4(1), Spring 2010] They evaluated how 10 different types prevented deer from browsing  deer-fave yews (Taxus cuspidata) over two growing seasons. The egg-based products – Deer-Away Big Game Repellent,  Bobbex, Liquid Fence – were generally most effective. They found Hinder, made of ammonium soaps of fatty acids, and Thiram-based (tetramethylthiuram disulfide) Chew-Not which is no longer available, nearly as effective as the egg-based formulations. Their findings show Deer Solution, , Repellex systemic tablets, Plantskydd, and coyote urine least effective.

Research from Cornell University in Ithaca, New York also found egg-based solutions most effective among the repellents they tested on yews over 10-weeks. [Reference: Curtis PD, Boulanger JR, Relative Effectiveness of Repellents for Preventing Deer Damage to Japanese Yews, HortTechnology 20(4), August 2010]

This does not mean that egg-based repellents work for all plants and on all deer. Only a properly constructed, designed, and maintained physical fence can provide real protection. For a small garden, such as a vegetable plot, a 5’ or 6’ tall fence should suffice.  Deer need running room to leap over fences so minimizing this helps to keep them out of small enclosed spaces. Large areas – think an expansive yard or garden – need fencing 8’ to 10’ tall to keep deer out. Also, any fencing needs to be hole-free for obvious reasons and secure enough at the lower edges to keep deer from sneaking in under the fence.

Homeowners can also spring for deer-tolerant plants. Follow this link  for a University of Connecticut Home and Garden fact sheet – scroll down to and click on “Deer and Plants They May or May Not Eat, Maybe!” or check out the books, Deer Proofing Your Yard & Garden by Rhonda Massingham Hart and Gardening in Deer Country by Vincent Drzewucki, Jr. All these sources provide good background information on plants deer may not eat but the best information on deer-tolerant plants will likely come from local garden experts and your own trial and error.

OLYMPUS DIGITAL CAMERADifferent deer have different tastes. I’m “blessed” to have deer neighbors that nibble on one type of early narcissus, a supposedly deer-tolerant bulb. I’ve also found a fish-based spray to deter deer browsing in my gardens while the proprietor of a local garden center has had the opposite experience.

This leads back to the importance of knowing which repellents work best and which don’t work at all … so help out with the CAES study. Fill out the HomeBrewedDeerRepellents survey and check back here next winter for any reported results. With everyone’s help we may face next year with a bit more information on the best means for deterring deer.

Digiprove sealCopyright secured by Digiprove © 2011 Joene Hendry

12 comments for “Researchers want your homemade deer repellent concoction

  1. April 9, 2011 at 6:48 pm

    Really interesting study underway. I don’t have a homemade recipe, but I do know that a newly planted plant fresh out of its nursery pot will be eaten, even if the same plant is never touched normally. It’s the high level of salts in the fertilizer that attracts them, and anything in a pot is highly fertilized. I have learned that no repellent works on new transplants, they have to be completely caged until the fertilizer is gone.

  2. joenesgarden
    April 9, 2011 at 7:41 pm

    Laurrie, Have you found this on newly transplanted greenery that deer don’t eat such as lavender or sage? If so it might be helpful to pass this on to the CAES researchers.

    I’ve not had similar experiences with new transplants.

  3. April 10, 2011 at 10:20 pm

    I wish I had a ‘recipe’ to share.

    We have a large herd of deer that ranges across here but they are not a problem for the gardens. I suspect because they have plentiful food in adjoining woods and our yard has a large dog who rushes out, barking. They do keep down the encroachment of the exotic Japanese honeysuckle.

    • joenesgarden
      April 10, 2011 at 11:21 pm

      Your dog must be keeping the deer away, Nell Jean. We have a large herd of deer in nearby woods and have to use fencing, repellents, and plant greenery deer don’t usually eat. Neighbors with dogs also have deer issues since no one leaves their dog out at night – a coyote or fisher would attack.

  4. April 11, 2011 at 6:26 am

    Joene, there were definite signs of deer here over the winter, when the dogs were unable to enforce their property rights in the deep snow – thank goodness they seem to have retreated. Interesting project, though from what friends say, a hungry deer is almost unstoppable…

    • joenesgarden
      April 11, 2011 at 7:51 am

      Your friends are correct, Cyndy. During winter fencing is the only thing that keeps them from eating my shrubs. Repellents become part of the growing season routine. With research we may learn more about what works best.

  5. April 12, 2011 at 1:46 pm

    Joene, This is a really interesting (and useful!) research project. Meanwhile, in Maine, the state Department of Inland Fisheries and Wildlife is worried about the decline of the deer herd and has adopted a new plan for increasing the number of deer in the state! (Honest; I’m not making this up.)

    • joenesgarden
      April 12, 2011 at 2:29 pm

      Jean, perhaps the solution is for the Maine Dept. of Inland Fisheries and Wildlife to hook up with their counterpart in CT. We have more than enough deer to share.

  6. April 13, 2011 at 3:38 pm

    Joene, I’ll be very interested to see if any of the home remedies work as well as the commercial ones. My gut feeling is that a few of them will. As you mention, knowing what ‘your’ deer will eat is the biggest issue. I often to talk to people who live very close to me and they have totally opposite expereinces with deer in their gardens. Unfortunately, it really is a trial and error process. Great post with lots of useful info!

    • joenesgarden
      April 13, 2011 at 4:51 pm

      Thanks, Debbie. I hope the research will reveal one or two ingredients most repellent to deer. It will be so helpful to add a home-remedy to the list of deer repellent choices so we all have multiple concoctions from which to choose.

  7. Jackie F
    February 9, 2012 at 2:16 pm

    Check out the new book, Creating a Deer & Rabbit Proof Garden.
    It is the best book out there.
    describes in great detail 160 deer/rabbit plants with over 400 color photo’s
    Great tips and techniques.
    I srongly recommend it

Leave a Reply

%d bloggers like this: