Yew plants require deep, well aerated, drained and fertile soil to grow and thrive in.
It will not matter if the yew is being planted to be a tree or as part of a hedge, if you do not provide these conditions you may end up with a yew hedge that is not growing properly.
One of the most common problems I have seen with yew hedges are that the plants are not uniform in size and colour along the length of hedge, some of the plants may have brown leaves, almost appearing to be dying, or significantly smaller in size to the rest.
These symptoms can be caused by some or all of the following:
Yew Hedge Problems
It can look like the hedge is dying in places but if you look closer at the soil conditions in these areas you will most likely find the soil to be of poor quality or waterlogged.
Planting A Yew Hedge In Clay Soil
Yew hedges do not like to have their roots in wet soil (known as wet feet)– it will cause the plant stress, it will not grow properly and may even cause it to die.
When you are preparing your trench to plant the hedge into – do not neglect wet areas. If there is a wet area under foot you should examine where the water is coming from and fix the source of the problem by installing a land drain.
If there is no apparent reason for the wet area you should drain the area anyway, so the water is taken away from where the roots of the hedge will be.
There is no other way around this – if you plant your hedge into wet soil it will die and you will be left with a dead plant and a gap in your hedge.
Yew Hedge Growth Rate
A yew hedge needs good quality, free draining soil which has plenty of nutrients to grow well in.
If you plant it in poor quality subsoil or tipped fill from a building site it will struggle to grow.
In some cases there may be no choice where the hedge needs to be planted and if the area is on back filled subsoil or site fill the following points should be followed:
1. Mark out the area where the hedge is going
2. Dig out a trench 2 to 3 feet wide and 3 to 4 feet deep- a mini digger would be advised for this.
3. Install a land drain at the bottom of the dug out trench.
4. Fill in 4 to 6 inches of sand and stones on top of the drainage pipe.
5. Fill in good quality topsoil mixed with farmyard manure or compost and mix thoroughly – using a rototiller will ease the amount of manual labour.
This prepared hedge base will be good for most types of hedges – it’s just that yew plants need this high quality base for them to thrive.
Yew Hedge Spacing
Gently tease the roots from the base of the plants and place the yew plant into the ground every 18 inches to 24 inches apart.
*Important note- The stem of the yew plant must not be below the surface of the soil or it will rot. It can be planted a little shallow but too deep and it will rot the stem.
The stem of the plant should be free from soil with just the crown of the roots visible.
Firm the plant into the hedge bed and apply a chipped bark mulch around it – keeping all soil and mulch 4” away from the stem.
Why Is My Yew Hedge Turning Brown
Yew hedges although hardy, their foliage will turn brown if there are stress factors acting on the plant. In the image above one of these stress factors is “wet feet” where the plants roots are continually in wet soil.
Cold Weather Damage in Yew Plants
Another stress factor is winter damage – where the plant is subject to a quick reduction in temperature such as a hard frost and strong sunshine coupled with drought during cold winter months. Young plants will be more susceptible to damage from this type of stress than a more established well rooted plant.
Salt and Yew Plants
Yew plants are susceptible to damage from salt spread from gritters along footpaths and roads during the icy winter months. The first symptoms are fully seen in spring when the salt is washed down into the roots of the soil. This will cause the plant to temporarily turn brown. This is normally not a permanent problem as the salts will leach out of the ground again when enough rainfall washes it away.
Damage To The Plant
If the bark of your yew plant gets damaged this can be a major cause of stress. They do not like to get their bark or branches damaged in any way. A lot of people have thought they were doing good by strimming around the base of the plants to remove weeds and grass which could smother the plant. The bark gets damaged by the strimmer line and through time the plant may wilt and die. The majority of the time people don’t know why. If you damage the bark even in a small way it will majorly affect the development of the plant.
Another way the plant gets damaged is by the roots getting cut or broken when the soil around the base is being weeded. The gardeners fork or spade is digging around the base of the plant and unintentionally breaks the roots off the bottom of the plant. A couple of weeks later the plant is brown and no one knows why.
The next time you are cutting your yew hedge with hedge trimmers be aware where you are putting the base of your steps or where you place your ladder so that you do not damage the branches or trunk. Yew trees thrived in graveyards for a reason – they had nobody to disturb them.
Yew Tree Reading
I have a book called “Yew” by Fred Hageneder and it is one of the best books you could read if you have an interest in these fascinating trees. It is available in hardback and has been hailed as the must read of all yew tree books. It provides an in depth look at the species and its colourful history.
(Shonil Bhagwat, University of Oxford)