Deer are mammals, usually living in woodland or scrubby areas from where they make forays into gardens. They may visit gardens singly but often several animals will be feeding on the plants.

Deer will feed on a very wide range of plants, with runner bean, beetroot, blackberry, raspberry, strawberry, evergreen azaleas, camellia, roses, holly, ivy, rhododendron, Viburnum tinus, hardy geraniums, Sedum, tulip and grape hyacinth often being heavily damaged. New plantings are particularly at risk. Deer are capable of eating thorny plants and also some, such as yew, which are poisonous to cattle and sheep. They also eat large amounts of fruits and berries in the autumn. These include acorns, chestnuts, beech mast, apples and mountain ash berries. 

For more information on the deer species found in Britain visit The Mammal Society website 
 

Deer often go unseen in gardens as they do most of their feeding between dusk and dawn. They cause a range of damage including:

• Shoots, flower buds and foliage stripped off plants, feeding often occurring overnight
• Woody stems often have a ragged cut end where a deer has bitten part way through the stem and then tugged the shoot off
• Deer will eat tree bark, mainly in winter when other food is scarce
• Another frequent form of bark damage is fraying. This occurs in summer when male deer rub their heads against the trunks of sapling trees in order to remove the outer skin or velvet from a new set of antlers, or when they are scent-marking their territories. The antlers make vertical cuts in the bark, which peels off and exposes the inner wood. Such damage often causes growth above the point of damage to dry up and die

Information on living with deer is available from the RSPCA

Deer resistant plants

While deer can eat most plants, especially those that are recently planted, there are some plants that are usually left alone. Using evidence gathered in a RHS survey of the gardening public’s experience in 2018 we  updated a list of plants that deer are less likely to damage which can be found here. It is also worthwhile observing which plants grow successfully in other gardens nearby, as that will provide some information on the feeding preferences of the local deer population.

Netting and fencing

The most effective way of stopping deer is to exclude them from gardens with netting or fences but these need to be robust and relatively tall. Deer can squeeze through small gaps under fencing or leap over barriers that are too low.

Wire mesh fencing should be 1.5m (5ft) tall for muntjac and 1.8m (6ft) for other deer, and a heavy duty type of wire like that used to fence sheep or pigs should be used in the lower half. The bottom edge should be pegged to the ground to stop deer lifting the wire and squeezing underneath. The maximum mesh size should be 20 x 15cm (8 x 6in) for most deer but 7.5 x 7.5cm (3 x 3in) where muntjac are a problem.

Entrances to the garden need deer-proof gates. An electric fence, as used to confine farm livestock, is often ineffective against deer and may be damaged if deer are startled and try to run through it. Horizontal strands of plain or barbed wire are unlikely to be effective as roe deer can squeeze through gaps of 30cm (1ft).

Hedges can be an effective barrier if they are suitably tall and solid enough to stop deer pushing through. 

A ditch on the outside will improve the effectiveness of fences or hedging.

Further information on fencing for deer can be found from Forest Research

Protecting young trees

Tree guards will be necessary to protect young trees from fraying if the garden is not fenced. The best way of doing this is to place three or four stakes or poles around the trunk so that the deer cannot get close enough to damage the bark. Additional protection can be given with wire netting. A height of 120cm (4ft) is adequate for roe deer but taller guards are needed for larger deer such as the red or fallow. The leading shoots of young trees can be protected by twisting sheep's wool around them. This will need adjustment from time to time during the growing season.

Animal repellents and scaring devices

Animal deterrent sprays based on aluminium ammonium sulphate (e.g. Vitax Stay Off or Growing Success Animal Repellent) or calcium cloride (e.g. Grazers G1) may discourage deer from feeding but need frequent application in spring and summer to keep pace with new growth. Such sprays may also divert deer onto feeding on other plants that have previously been left alone.

Ultra-sonic scaring devices emit a high pitched sound that is inaudible to humans but loud to animals such as deer. These devices can be effective initially but the deterrent effect is likely to be reduced once deer have become familiar with the noise.

Another repellent that can be tried is placing human hair in bags made from muslin or old nylon tights in places where deer are feeding or entering gardens. Some people find this effective but it does not work in most gardens.

Deer keep well away from dogs, so the scent and sound of a dog in the garden may be helpful.

Shooting

This generally cannot be done in a humane, safe and legal manner in private gardens.

The muntjac is a small deer and it grazes plants up to a height of about 1m (3¼ft); red deer is the largest species in Britain and can feed up to a height of about 1.5m (5ft). The most frequent deer species in British gardens are roe deer and muntjac, both of which are becoming more widespread. Other deer that can visit gardens in some parts of Britain are fallow deer and sika deer. Deer have no effective natural enemies in Britain and have become more numerous in recent decades.

Like all animals deer can suffer a variety of diseases if you find a dead or dying deer you can report it via Garden Wildlife Health website.