The Magnificent Yew – Help – I’ve got poor drainage! (Part 3)


Even if you have the disadvantage of poorly draining, or even heavy clay, soil, don’t despair and don’t think you can’t plant Yew. You can – but you will have to prepare its new home before it moves in. And one thing before we start – please don’t blame the Yew for having to do this extra work as it will be necessary if you want to plant anything other than the relatively short list of clay-loving plants.

So, what to do?

The following is based on advice given by the RHS and if it appears daunting, it is worth remembering that few soil types are more fertile than properly improved clay:


Don’t work or walk on clay soil when its wet as it will become puddled and compacted – having to put this right will add greatly and unnecessarily to the workload.

Dig in autumn and early winter when relatively dry. Once it’s rained in winter, the chances are you won’t be able to resume working on it until spring – and by then you’ll be up against warm weather baking it solid.

Frost will break down clay soils so, particularly if you garden in a wet region, dig the soil into narrow ridges to allow frost maximum access.

Creating 25cm mounds (in effect, a raised bed) for planting can help prevent root damage from waterlogging.

When you have dug the hole for planting, thoroughly break up its bottom and sides with a garden fork.

Delay planting until late winter or early spring so the dormant roots will have to spend less time in cold, wet soil.


Dig in as much organic matter as you can. Manure (with straw still visible) or composted bark are ideal; leafmould, leaf litter and garden or mushroom compost will also be beneficial, but not to the same extent.

Digging in coarse grit, gravel or sand is a common solution, but the quantity required to make a difference is such that it’s only really practical on a small scale.

Add a 7.5cm, well-rotted organic mulch at the base of plants at the beginning of spring, leaving a similar gap of 7.5cm between the mulch and plants to reduce the chance of rots developing.

Repeat regularly throughout the growing season.

It is also possible to improve a heavy soil by altering its chemical make-up. Some (though not all) clay soils will benefit from adding calcium, normally in the form of gypsum, the active ingredient in many commercially available clay improvers. However, if the soil is acid, then lime is used to achieve the same effect. However, you should test the treatment in a small area first as soils do not respond in a universal manner when either chemical is added.

Having a heavy soil is not the end and there’re many glorious gardens cultivated on clay to prove the point. But if you can’t face the task of a heavy soil makeover, there is one easy, infallible solution (besides choosing water-tolerant Hornbeam instead) that will allow you to enjoy the company of a Yew or two.

All will be revealed in Part 4…