Deer Fencing

Deer Fencing

​Nothing frustrates a gardener more than wildlife eating your plants. Some of the biggest complaints involve deer, rodents, rabbits, chipmunks, squirrels, and groundhogs. Where I live, we seem to have very few small mammals (except for voles), probably due to large numbers of predators such as foxes, coyotes, and birds of prey. We rarely see rabbits, chipmunks, squirrels, or groundhogs (I do not think we have ever seen a groundhog on our property). What we do have a problem with, in central Wisconsin, however, is deer. During our first year living here, we were involved in three car accidents, all caused by deer.

​If you spend any time Googling “deer fencing,” you will find many varied opinions. Most of those solutions have not worked for us. I can tell you what has not worked for us in central Wisconsin and what currently seems to be working (fingers crossed it continues to work). We have a large fenced-in garden, about a half-acre in size, which makes it more challenging to keep deer out, mostly due to cost. A large garden, especially in a rural setting, also makes it easier for deer to jump since they have plenty of room outside and inside to jump. Our garden contains our vegetable garden, fruit trees, wine and table grapes, raspberries, blackberries, blueberries, and rhubarb. If you do not want to read the entire post about our fencing journey here is a list of what did not work for us: a six-foot electric fence, fishing line around a 6-foot electric fence, an 8-foot non-electric fence, and a five-foot outer fence around an eight-foot fence spaced 5-feet apart. Here is what worked (so far): two eight-foot fences spaced five feet apart.

Electric Fence

We started with a six-foot electric fence that was solar-powered. We knew a deer could easily jump this height, but our research suggested that the deer would nose the fence first. After being shocked the deer would then ignore the fence. We were also limited by budget and could not afford a taller fence. This fence worked well for several years until it suddenly did not. Once the deer learned there were tasty plants inside the fence they continued to jump it. However, we mostly had a problem with the deer jumping the fence in the fall to eat all the brassicas made sweet by frost. Eventually, however, they started jumping it more frequently. We would put netting over high-priority crops and spray liquid fence, but these were temporary solutions.

Our first deer fence, a six foot electric fence with chicken wire at the bottom to reduce small mammal entry.

Fishing Line

​We read that if you string fishing line around your garden the deer will not be able to see it but will feel it walking past and get scared. So, we strung fishing line around our entire garden, outside our 6-foot fence. For us, all the deer did was break the line and then jump the fence. Maybe this would work better if you used a stronger fishing line, but we decided instead to increase the height of our fence.

T-Post Extenders

​We decided to upgrade our original six-foot fence with T-post extenders from The Fence Department (Extend-A-Post) to turn it into an eight-foot fence. We removed the solar-powered electric unit, since at this point, it had stopped working anyway. The problem with T-posts was that they only went two feet into the ground and we could not put much tension on the lines because the T-posts, especially with the extenders on top, were not stable enough at the corners even with anchors. We had lots of sagging lines and the deer were able to jump the fence. We hoped that if we fixed the sagging lines to make it consistently eight-feet high this would solve our problems. At this point, we also upgraded to an eight-foot gate. Rather than make our own we purchased a kit from Deer Busters, which was easy to install (although it does involve concreting in the posts), but the highest they sell is eight feet tall, which as we discovered, is not sufficient to keep deer out.

T-post extenders can be added to T-posts to add an additional two feet to the height of your fence. They are not very stable so cannot hold much tension, particularly at the corners.

Reinforced 4x4 Corners

​To solve our sagging fence problems my husband decided to make reinforced corners out of 4x4s so we could put more tension on the wire and eliminate the worst of the sagging. We bought 12-foot pressure-treated 4x4s and cemented three into the ground four feet deep with 2x4 reinforcements between each 4x4. The corners turned out beautifully, and we eliminated the worst of the sagging, however, the deer continued to jump the fence easily.

Reinforced corners of our original eight-foot deer fence which allowed tensioning of the wire to reduce sagging of the deer netting.

Double Fence

​Multiple times I read deer can jump high or far but not both. Since we had one deer that insisted on jumping our 8-foot fence every night and eating all my cabbages, we decided to add on a second outer fence. From what I read you only needed a short second fence (some people even claim two, four-foot fences spaced five feet apart are sufficient), so we rounded up all our extra T-posts and made a second fence using plastic snow fencing, approximately five foot high around our eight-foot fence with a five-foot gap in between the two fences. Unfortunately, the deer continued to jump both fences every night, eating up my peas, beans, and the rest of my brassicas. I should also mention that normally liquid fence works well for us to keep deer damage at bay but this year (2024) was one of the wettest on record with massive amounts of rain (20 inches in both May and June). The rain washed away the liquid fence spray as fast as we could apply it. At this point we were second-guessing whether we should have just hired a company to install a 12-foot welded wire fence, but earlier quotes had been $5000 for materials alone plus the cost of installation. We assumed that even if we could find someone to install a fence, the cost would be $10,000-$15,000 which was not in the budget. However, we had probably spent at least $6,000 on fences that did not work so in hindsight maybe paying for a 12-foot fence installation would have been preferable. 

Eight foot tall gate from Deer Busters. Tensioners at each corner to reduce sagging.

Double Eight Foot Fences

Since we had already bought the snow fencing, we decided to try one more time to build a double fence, but this time we made the second one eight feet tall to match our first one. This is one of the recommendations by the Minnesota Department of natural resources (see link for other recommendations). We found 10-foot T-posts (not cheap) at Home Depot, so we removed the snow fencing from the shorter T-posts and replaced them with the bigger ones. Between the shorter and taller second fence, my poor husband pounded in about 80 T-posts over a two-week period. We then re-assembled the snow fencing on the taller T-posts and added deer netting to fill in the gap below. We also had to rig up fencing along the gate but this had to be removable at the bottom to enter the garden (we used step-in posts). Thus far, the deer have not managed to jump both eight-foot fences, and hopefully, this will continue in the years to come.

While double 8 foot fences appears to work well to keep deer out, it is not the most attractive fencing option. This is the gate where we needed to make the fencing movable for access. In the future we may upgrade to two eight foot gates.

Conclusion

By the time we put in two eight-foot fences, we had lived on our property for eight years. In hindsight, I wished we had saved up money to have a company install a 12-foot welded wire fence from the beginning. It would probably have cost the same amount we spent over the years on temporary solutions, plus it would look more attractive than two 8-foot fences cobbled together with T-posts, T-post extenders, and multiple types of netting. One piece of advice I can give is to deal with infrastructure first. Get your fencing, sheds, animal coops, etc. in place and make them properly, before you go all out on fruit trees, vegetables, or animals. Someday, maybe I will take that advice!

References and Resources

1. The Fence Department. https://www.extendapost.com/
2. Deer Busters. https://www.deerbusters.com/?utm_source=google&utm_medium=cpc&utm_campaign=%28ROI%29%20Brand&utm_id=919130523&utm_content=51617798131&utm_term=deer%20busters&_vsrefdom=googleppc&gad_source=1&gclid=Cj0KCQjwwae1BhC_ARIsAK4JfrzvDHnR6ABP71ZKsajysIl1g2JC9Iawhg5iI9C-dpS5i28HuVYGcB4aAoDUEALw_wcB
3. Deer fencing. Minnesota Department of Natural Resources. https://www.dnr.state.mn.us/mammals/deer/management/deer-fencing.html#:~:text=Comprised%20of%20at%20least%205,48%20inches%20above%20the%20ground.