Thuja Green Giant and Deer

Like most children, when I was young I loved deer. In books and cartoons they are always portrayed as shy and sweet. It was only when I took up gardening that I learned the truth – deer are not the gardener’s friend. They are aggressive in looking for food, and bold enough to venture into gardens, especially early in the morning, or at dusk, when no-one is around, or when they are hidden by the growing shadows.

Finding plants that deer will ignore is a necessity for gardeners in rural areas – unless you invest in a deer-proof fence, deer netting or an electric fence. White-tailed deer can jump almost 8 feet height, so a small fence is not going to cut it, and larger ones start to run expensive if you have a larger property. A fence is never a guarantee of a deer-free garden, so growing plants that deer don’t like is a better way to start.

The second necessity in many gardens is a hedge. Hedges and screens protect your property from wind and drifting snow, and they give you privacy from neighbors. You may get on very well with your neighbors (or you may not!) but you certainly don’t want them monitoring your every move. This means that putting in a hedge is usually a first priority when you move into a new home. A very popular group of plants for hedging are the arborvitae trees, and among these, the stand-out variety for rapid growth is ‘Green Giant’. This hybrid tree is far and away the most popular hedging choice when speed, height and density are your priorities. So how does this plant stand up against deer?

Bambi meets the Green Giant

This might sound more like the latest movie at the drive-in (I know, I know, there are sadly almost none left anymore) but this is exactly the situation – what happens when that cute little animal meets the big tough tree? The answer to that million-dollar question seems to be – not very much. Although with deer nothing is iron-clad, it seems that arborvitae in general, and ‘Green Giant’ in particular, are not on the tasting menu for deer at all.

Practical experience, supported by an internet search, shows that there is general agreement to put Thuja Green Giant firmly on the list of ‘deer-proof’ plants. Now immediately someone is going to say, “But deer ate my arborvitae!” and I am going to ask them, “What kind do you have?” You see, to you and I, all arborvitae may look similar, but not to a deer. The eastern arborvitae, also called white cedar or Thuja occidentalis, is (sadly) a favorite of deer, and so plants like ‘Emerald Green’ do need protection. On the other hand, western redcedar, Thuja plicata, is not attractive to deer at all. That plant is one of the parents of ‘Green Giant’, so whatever it is in western redcedar that deer don’t like, its offspring has it too.

What kind of deer is That?

Like the arborvitae, not all deer are the same either. There are two basic species in North America, with several local subspecies. The most common is the whitetail deer, Odocoileus virginianus, which lives mostly in the eastern states, but is also found to some degree in every other state except for California, Nevada, and Utah. As their name suggests, whitetail deer are easy to identify, at least when they lift their tail to make their famous ‘white flag’ gesture. The top of the tail is brown with a dark stripe down it, but the underside is pure white, and lifting the tail also reveals a white rump patch. Whitetail deer are able – and usually willing – to live near humans, so they are also the ones most often seen by us. With perhaps 14 million of them around, they can be hard to miss. In winter they gather together in groups – ‘yard up’ – on some part of their range. That is why the two or three you saw all summer suddenly become 50 when the snow starts to fly.

The larger mule deer, Odocoileus hemionus, is mostly found in western states, where it has a couple of subspecies, the Sitka deer in Alaska and the Columbia blacktail along the Pacific coast. They can also be found as far east as Texas. Mule deer spend summer in the mountains, but migrate down into valleys for the winter, when they are more likely to be seen – and come into gardens. They are easily identified by their large ears, like those of a mule, and that of course is why they got their name.

And the Winner Is. . .

So, when we read of plants eaten by deer, we also need to take into account the location – since each species has different feeding preferences – and the time of year. In a severe winter, with thick snow and limited food, just like humans in a famine, deer will eat plants that they otherwise would pass right by. With animals, nothing is guaranteed, but when it comes to putting in plants that deer will usually leave alone, Thuja Green Giant is still the number one choice both among arborvitae, and among just about any other hedging plant. When it comes to giving you the best chance of making a hedge that deer will leave alone, the Green Giant wins every time.

Finally, although a full-scale deer fence may be prohibitive, once you have a nice, dense Green Giant hedge around your property – and that won’t be very long at all – then putting a shorter, cheaper fence tight along the backside of it will keep deer from pushing through. Inside your garden is now going to become truly deer-proof. This leaves you free to grow whatever you want, without having to check it is not on the ‘preferred diet’ list of your local deer – whatever species they happen to be.