How to make a garden hedge

Hedging at Les Jardin du Manoir d'Eyrignac
Hedging at Les Jardin du Manoir d’Eyrignac

Hedges have been an integral part of gardens since the earliest times and encompass a vast range of ideas. Their main purpose though is to divide up space; be it marking the boundaries of a garden or dividing up the area within them. Many people shy away from hedges on the grounds that they take too much work to maintain or will take to long to establish. While it is true a formal hedge needs cutting at least once a year and you have to allow time for the plants to grow nothing provides the same sense of structure to a garden, just look at Hidcote Manor!

Choosing a hedge plant

When deciding on a hedge it has to be remembered that you are going to need a lot of the same plant and its going to be there for a long time. Cost and availability are clearly going to be important, particularly if a long hedge is planned. It also has to be suitable to its location: is the soil limy, shallow, free draining, water-logged? Also is the site exposed or sheltered, in open sun or shade? A good hedging plant needs to be hardy and suited to its location, the last thing you want is to lose chunks of you hedge the first hard winter, but also has to be amenable to being treated as a hedge. Most hedges are keep clipped and a good hedging plant needs to be a mass of dense smart leaves; as an open habit will never look good. The size of the leaves also matters as large leaves that look tatty when cut with shears; meaning they are best suited to informal hedges and screens, unless you have he time and patience to trim them carefully with secateurs.

Mixed hedges

Hedging at Chateau de Losse
Hedging at Chateau de Losse

Nobody said a hedge has to be only one type of plant, in fact most hedges usually end up with some lodgers in them over time. The red flowered climber Tropaeolum speciosum is often seen scrambling through yew hedges to great effect and wild clematis and ivy are seen doing the same thing in field hedges. So long as the hedge is sufficiently established and the climber not too vigorous a great range of combinations will add to a hedge. But you do not need to restrict yourself to mixing in climbers; the plain green of a hedge can be broken up but the inclusion of variegated plants in the mix. Care has to be taken to ensure one doesn’t swamp the other but say a plain green hedge with variegated buttress can lift an otherwise ordinary hedge. Mixed hedges are also sometimes used to recreate a more natural hedge for wildlife. For example 75% Hawthorn (Crataegus monogyna), 10% Field Maple (Viburnum opulus), 5% Beech (Fagus sylvatica), 5% Field Maple (Acer campestre) and 5% Holly (Ilex aquifolium) spaced 300mm apart, or 500mm apart in a pair of staggered double row 400mm apart, will produce a pleasing effect. Better still have a good look at the near by hedges and copy those, being careful not to be tempted by elder (Sambucus racemosa) as it’s short lived and tends to swap its neighbours and you will probably end up with self seeding themselves anyway!

Formal or Informal

Does a hedge have to be cut? The traditional image is of carefully trimmed walls of green, but where a more gentle appearance is called for a natural unkempt look can be more fitting. In a larger garden a screen of bushes can serve to define areas. For example a wild flower area could be separated from the remainder of the garden by an uncut screen of hawthorn and if needs be the side facing a more formal area could be keep cut. Even smaller gardens could benefit from an edging of lavender left to grow over the edge of a path to soften it.

Wildlife and hedges

There is no doubt that wildlife benefits from gardens, it is a two way street, and shrubs provide valuable cover and nesting sites so a hedge will benefit the wildlife in the garden which in turn adds to the garden. To this end any hedge cutting must be avoided if it could disturbed nesting birds, which in the UK, at least, is a criminal offence. In the UK the RSPB recommend that hedge are not cut from early March until the end of August for this reason, but these are guidelines and some years bird nesting could extend beyond this time frame.

Establishing hedges

A hedge is a long term investment in a garden so prior to planting the area needs to be well prepared. The ground needs to be clear of any perennial weeds which will be very difficult to eradicate once the hedge is growing. Any drainage problems have to be sorted out and with plants which will not tolerate water-logging, like Yew, it is prudent to install effective land-drains in all but the most free draining soils. As hedges are made up of closely packed large shrubs they tend to be greedy neighbours as their roots spread out looking for food and moisture and in some instances setting a barrier between them and any adjoining planting may be a sound investment, corrugated sheeting, builders damp proof membrane or cheap pond liner would suffice.

Maintaining a hedge

Topiary at Les Jardins Suspendus de Marqueyssac
Topiary at Les Jardins Suspendus de Marqueyssac

Hedge cutting became much easier once the powered hedge cutter became widely available but still most hedges will need cutting at least once a year; so it is best to plan ahead to make the task as easy as possible. First off make sure you not only leave room for the hedge to grow when you first plant it, but leave plenty of room to get in to cut it. Most plants will only create leaves where there is sun so cutting the hedge so it slopes slightly in toward the top will help get light all the way down to the base, this is less of an issue with plants like Yew which seem un-bothered by shade but most will tend to develop an unsightly sparse bottom! While on the topic of hedge cutting you should consider how high you actually need your hedge, yes a 6 metre high hedge will no doubt afford you great privacy but is also going to create an awful lot of shade, and in the UK you are also in danger of falling fowl of the high hedges act! This aside you have to consider the practicalities of cutting the monster, a 1.8 metre high hedge will still block the line of sight but the top can still be cut from the ground or a small step. Steps always present plenty of opportunity for accidents without powered hedge cutter being thrown into the equation.

Clearing up after the cutting is also a time consuming exercise and specially so if the clipping land in a herbaceous border, so throw a dust sheet over the plants and the sheet can then be gathered up with the clippings contained. Once you’ve cleared up remember you removed a lot of nutrients with all your cutting and so the hedge will benefit with a feed of a slow acting fertiliser in spring.

Hedge Plant Selector

Plant Common Name Formal Hedges Informal Hedges Evergreen Shade Foliage Colour Flower Colour Single Row Spacing Double Row Spacing Comments
Acer campestre Field maple Yes No Green Pale green 450 A native plant that makes a good hedge, though more commonly used mixed with other plants. Very tolerant of soil and aspect it turns a very attractive pale gold in autumn.
Berberis darwinii Darwin’s barberry Yes Yes Yes Partial Green Orange 600 Makes a good impenetrable evergreen hedge 0.9m to 1.2m high. If left unclipped you get yellow spring flowers and blue berries in autumn. If clipped do so after flowering.
Buxus sempervirens Box Yes Yes Yes Green 450 to 600 The classic for dwarf compact hedges for edging and dividing up areas. The more vigorous forms will make 3.6 to 4.5 m high if wanted. The plant seems to attract snails!
Carpinus betulus Hornbeam Yes Partial Green 450 Like beech but more tolerant of heavy soils. A native plant it makes an excellent hedge in exposed locations.
Chamaecyparis lawsoniana Lawson’s cypress Yes Yes Green 450 to 600 Makes a good densse hedge but likes adequate moisture and good drainage. C. ‘Fletcheri’ makes a good dense hedge and being slower growing than the type takes longer to form a hedge but is less demanding of clipping there after.
Corylus avellana Hazel. Hazelnut Yes Partial Green 600 A native plant that is very tolerant of soil and aspect. Makes a good hedge on its own or mixed with other natives.
Crataegus monogyna Hawthorn, May Yes Partial Green White 300 The native Hawthorn is the commonest hedging plant in England forming many miles of hedgerow. It is very tolerant of dry and wet soils of all types in any situation. It makes a tough impenetrable hedge, often mixed with other native species. Very tolerant of being cut hard back.
X Cupressocyparis leylandii Leyland cypress Yes Yes Green 600 900 with 450 between the rows The rapid growth of this plant has lead to its over use and abuse by people looking for fast hedge. If keep regularly trimmed it make a good dense hedge but if left to grow it soon becomes a problem. Like most conifers it will not grow back from old wood and has a reputation for being poorly rooted.
Escallonia cultivars Yes Yes Yes Partial Green White through pink to red 450 As a formal hedge its smallish leaves repond well to clipping to form a neat hedge. As an infromal one it makes very attractive one and which will form hedges in a range of sizes depending which of the many cultivars are grown. Trim after flowering if necessary.
Fagus sylvatica Common Beech Yes Partial Green 450 This ever popular hedging plant is a hardy evergreen, happy in any soil but heavy waterlogged ones. When cut as a hedge it retains it leaves until they are replaced by the new leaves in spring. If grown as a pleached hedge you get the smooth silver trunks.
Fagus sylvatica Atropurpurea Group Copper Beech, Purple Beech Yes Partial Dark purple 450 As the plain green form but with dark purple leaves in summer.
Hedera helix Ivy Yes Yes Yes Green Green 450 Though not an obvious choice Ivy can make a very good hedge; it is easy to grow being happy in any reasonable garden soil, hardy and very tolerant of shade. To start it off some form of cheap fence is need for it to grow up, chestnut palling or cheap trellis will suffice, and once it gets going it can be clipped with shears once or twice a year. The fence will rot with time but by them the plants should be self-supporting. A vast range of cultivars are available to chose from.
Ilex x altaclerensis ‘Golden King’ Yes Yes Yes Yes Variegated green and gold 450 Makes an attrctive verigated hedge like the native holly and has it strengths and weaknesses but is if anything a little slower growing.
Ilex aquifolium Common Holly Yes Yes Yes Yes Green 450 A popular and native which makes a good intruder resistant hedge. It doesn’t transplant very well so it is normally sold in pots and its relative slow growth makes it expensive. It will make a hedge any where from 1.5 to 6.0 m high. It has two draw backs, apart from possibly its slow growth, its very sharp dead leaves it scatters across neighbouring borders and its attractiveness to rabbits which love its green bark.
Lavandula angustifolia ‘Hidcote’ Lavender Yes Yes Yes Grey Violet 300 This aromatic herb has long been used to create low hedges and will grow on most soils, though it prefers a free draining one, where it gets plenty of sunlight. It never makes a very dense hedge and resents being cut back into dead wood. Probably at its best when allowed to grow as an informal border edging and just clipped over once the flowers fade to keep it tidy.
Ligustrum ‘Aureum’ Golden Privet Yes Yes Partial Variegated green and gold White 300 400 to 450 with 200 between rows The gold verigated form of privet makes a good bright hedge. Semi-evergreen, only lossing its leaves in the coldest areas, it is tolerant of most soils and aspects. It will come back from being quiet hard pruned and will make a hedge anywhere from 1.2 to 1.8 m high. Buy plants 300 to 600 mm high and cut them back to 225 to 300 mm on planting
Ligustrum ovalifolium Common Privet Yes Yes Yes Variegated green and gold White 300 400 to 450 with 200 between rows Once a byword for suburbia privet has fallen out of fashion these days but is still makes a good hedge. Semi-evergreen, only lossing its leaves in the coldest areas, it is tolerant of most soils and aspects. It will come back from being quiet hard pruned and will make a hedge anywhere from 0.6 to 3.0 m high. Buy plants 300 to 600 mm high and cut them back to 225 to 300 mm on planting
Lonicera “Baggesen’s Gold” Yes Yes Gold 300 A gold form of Lonicers nitida. It can be used with the plain green form to create some interesting effects.
Lonicera nitida Yes Yes Yes Green 300 A very popular fast evergreen plant which can make a very dense hedge 1.2 to 1.35 m high. Its fast growth does means it needs regularly clipping, up to four times a year, but it is very tolerant of being cut hard back. It’s not terribly hardy and can damaged by cold winters so it is best where there is some shelter.
Photinia ‘Red Robin’ Yes Yes Partial Green with red shoots White 450 to 600 This evergreen New Zeland shrubs has started to become popular for hedging and makes a good hedge from 900 upto 1500 mm high. It is adaptable happy in most soils and situations it is best cut back once the red foliage starts to turn bronze, so getting the bright red shoots in spring.
Prunus lusitanica Portuguese laurel Yes Yes Yes Partial Green White 450 to 600 Can make a neat and close evergreen hedge with glossy dark green leaves. Its relatively large leaves mean it is best trimmed with secateurs though shears cut ones can still look very smart if you lack the time and/or patience.
Rosmarinus officinalis Rosemary Yes Yes Yes Grey green Blue 300 to 380 Its open habit make it better as an informal hedge but makes a sented hedge up to about 900mm. Though tolerant of most soils it does best in a warm sandy soil and can bea bit tender. Avoid cutting into old wood and ide3ally plant in spring.
Taxus baccata Yew Yes Yes Yes Green 450 to 600 The classic dense evergreen hedge and probably the best. Oftern over looked on the grounds of its much exaggerated slow growth it is reconed a Yew hedge can out last a brick wall. They tolerate most soils and situations including heavy shade and will make a hedge in 10 years if clipped regularly to encourage dense growth. A native plant is is very toxic to both humans and other animals. Its achilles heels is it will not tolerate waterlogging and so when planting it drainage should be installed in all but the most free draining soils.
Taxus baccata Aurea Group Golden Yew Yes Yes Yes Variegated green and gold 450 to 600 A gold variegated form of the classic hedge material. They tolerate most soils and situations including heavy shade and will make a hedge in 10 years if clipped regularly to encourage dense growth. A native plant is is very toxic to both humans and other animals. Its achilles heels is it will not tolerate waterlogging and so when planting it drainage should be installed in all but the most free draining soils.
Viburnum tinus Yes Yes Yes Yes Green White 600 Makes a good hardy evergreen hedge, V. ‘Eve Price’ is a particularly good dense form. Grows well on both chalk and non-chalk soils and tolerates both shade and maritime exposure.

 

Note: All measurements are in mm

Spacings are for guidance only, wider spacing will use fewer plants but will take longer establish. Normally use 450 mm to 600 mm tall plants, larger plants can be spaced further apart.

All the plants in this list will tolerate lime and grow in any reasonable garden soil.

Taxus baccata

Yew hedge at Warwick
Yew hedge at Warwick

The Yew tree is an easily recognisable plant of gardens and the countryside, being one of the few native British plants to be widely grown as an ornamental plant. It is a very adaptable plant growing in most situations with the exception of water logged ground and it responds very well to cutting. This, with its dense evergreen foliage has made a very popular material for hedging and topiary. It is also said it is slow growth is an advantage as it reduces the amount of cutting needed but it is not nearly as slow as is sometimes made out. Young plants can make 20 to 30 cm of growth a year; only slowing with age, as we all do!

Taxus baccata foliage
Taxus baccata foliage

Many selections have been made of Yew including fastigiated and variegated ones but it is still at its most impressive as a green hedge where it does an excellent job of defining spaces and providing a foil to the more colourful occupants of the garden. If planting it as a hedge make sure to prepare the site well, necessary with any hedge, and make sure the soil drains freely; even if this means installing drainage. Its dense evergreen foliage forms a very long lived hedge even in the shade and it has been said a yew hedge has a longer working life than a brick wall. The other advantage over a brick wall is its adaptability; creating a new opening in a wall is difficult and will always show up while with a yew hedge a saw and hedge clippers is all that is needed. Once the new opening is made the plants will soon break away as it happily forms new shoots from the old wood and so heal the wound made.

Taxus baccata 'Fastigiata'
Taxus baccata ‘Fastigiata’

It is remarkably good at growing away from old wood, I’ve seen yew trees cut down to ground level and shoot away from the stump. Hawthorn is the only other plant I know with such a strong regenerative ability. This is a very un-conifer like characteristic, but yews are not very conifer like though there appears know doubt that it should be classed as one.

Though now the yews are seen mainly as garden plants; it has been an important plant to humans for a long time. The Yew combines great long levity with a valuable wood which was prized was making bows, the most valuable weapon for most of human history. The ancient Greeks called the yew τόξο (or toxo) and the Romans called the yew taxus. As with any plant with such an important and long history with humanity a lot of superstitions have grown up around it, and this can be seen in its importance to druids and its presence in church yards. The Fortingall Yew at over 2000 years old is believed to be the oldest tree in Britian and grows in the churchyard of the village Fortingall in Perthshire.

Taxus baccata 'Elegantissima'
Taxus baccata ‘Elegantissima’

In 1753 Linnaeus named the Yew Taxus baccata L. in the second volume of “Species plantarum” the Taxus from the Latin for yew and the baccata from the Latin for berry after the distinctive red fleshy arils which enclose the black seed and look like berries.  It is only this red fleshy fruit-like part of the yew which is not poisonous as all other parts of the plants can kill humans if sufficient is eaten. Yew exists as separate male and female plants and so these colourful arils are only found on the female plants. The species Taxus baccata can be found as both male and female plants its cultivars will be only one sex and this should be considered when choosing one.

The Concise British Flora in Colour by W. Keble Martin

William Keble Martin was an amateur botanist in the must noble tradition of amateurs. That is to say he was not employed as one but was every bit as skilled and dedicated as any “professional” botanists. He was formally trained as a botanist but instead of following this path chose to be ordained and spent his entire working life working as a parish priest.

Throughout his life though he maintained his keen interest in botany and over a period of over sixty years studied and drew over 1400 native British plants in exquisite detail. It was not until he was 88 years old was this collection first published. These days the work of botanical illustrators is over looked, having been pushed aside by the ease, speed and ultimately cost of photography. The draw back of this is that a photograph can only ever be one example of a plant on a particular occasion, but plants are far more viable than this. The blunt tool of the camera can never isolate and capture the spirit or soul of a plant in the way a skilled artist can. Therefore the simple skilled illustrations in this book gives the reader a far clearer understanding of what a plant actually looks like than a “modern” glossy book ever can. I don’t know what lead Rev. Martin t to paint all these plants but I very much doubt anyone will try to repeat his work partly because he has already done it and partly because as he working away, colour photography was evolving from a laboratory experiment into mainstream use.

What he left us was though a remarkable tool for identifying British plants. Some of the names have moved on but still the modern alternative can readily be found by cross referencing with new publications. Sadly this book is no longer in print but can be found ridiculously cheap on the second-hand book market. . In a perfect world a publisher would take these illustrations and re-publisher them with up-to-date names but I don’t imagine the economics of the book world would make this a practical proposition.