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.

Dicksonia antarctica

OLYMPUS DIGITAL CAMERAAs one of the most popular examples of this fascinating and fashionable group of plants, it is seen more and more available for sale. Appearing like a fern on top of a short trunk its slow rate of growth is reflected in its relatively high price. There is a lot of confusion over its hardiness with some saying it is only hardy in the mildest areas of the UK while others, including Kew, say its foliage is hardy down to -2°C but the plant itself is hardy down to -10°C. Part of this may be expectation as it is only found in the tropical regions of the southern hemisphere, but may also reflect the location a particular plant has been collected from as it is found at up to 1000m above sea level where plants would be expected to be more cold tolerant. With that in mind, and considering the cost of the plants it may be as well to adopt a cautious approach as frost below -10°C are not unknown in most parts of the UK and provide some frost protection. This is commonly achieved by wrapping the plants in horticultural fleece or straw secured with chicken wire.

Dicksonia antarctica
Dicksonia antarctica

Dicksonia Antarctica Labill. Thrives in cool damp situations: given time and the right conditions it can achieve a 3 metre trunk and 2.5 metre long fronds. To do well it needs plenty of water and given enough water it is quite tolerant of exposure to sun. As you might expect from its natural habitat it does best in a humus rich acid loam but it is quite capable of growing in most soils, even poorly drained ones. There slow rate of grow makes them very suitable a pot plants, which allows them to be moved indoors in cold weather, but they do resent being pot bound. The strange structure of the trunks means the top of a tree fern can be cut off and will regrow if being planted; but the lower potion will not as it is composed of dead material.

The extant species of tree ferns are a remnant of a far greater group which helped lay

Dicksonia antarctica trunk cross section
Dicksonia antarctica trunk cross section

down the coal seams mined today. They do not form a taxonomic group as such and the term only refers to any tree with a wood like trunk raising the fronds off the ground. In UK gardens Dicksonia Antarctica Labill.is the species most commonly found and as originally described by Jacques J.H. de Labillardière. M. Labillardière published his description in the second volume of his to volume Novae Hollandiae Plantarum Specimen, which was the first flora published of Australia (or New Holland as it was then known). The journey from Australia to the floras publication in 1806 was anything but straight forward. Labillardière was a naturalist attached to the expedition the French sent out to find what had happened to the expedition lead by Jean-François de Galaup, comte de Lapérouse. They failed to find the lost expedition but did explore parts of Australia, New Zealand and surrounding islands. While they were away The French Revolutionary wars were causing upheaval in Europe and on reaching Java the expeditions scientific collections were seized by the British. It was only by appealing through influential British contacts that he was able to secure their return and so publish their descriptions.

References:

Dicksonia trunk showing aboriginal carving
Dicksonia trunk showing aboriginal carving

http://www.kew.org/plants-fungi/Dicksonia-antarctica.htm

Encyclopaedia of Ferns by David L. Jones

Hardy Garden Plants (3rd Edition) by Graham Stuart Thomas

http://www.forestferns.co.uk/

‘The International Plant Names Index (2012). Published on the Internet http://www.ipni.org [accessed 24 June 2013]

Novae Hollandiae Plantarum Specimen by Jacques J.H. de Labillardière

Olearia x macrodonta

Olearia macrodonta bush
Olearia macrodonta

The “New Zealand Holly” rightly earns is common name; its pointy edged leaves make look a lot like a grey holly leaf. They can be a little tender but are sufficiently tolerant of salt laden winds that that do well near the coast. This makes them a valuable plant in seaside gardens where their tolerance of salt and the relative absence of hard frosts makes them well suited. In all but the most exposed gardens they can be grown; coming through all but the worst winters with little or no damage. They are very wide spread in North West Scotland, to the point of almost being naturalised.

Olearia macrodonta bark
Olearia macrodonta bark

While evergreen like holly; the leaves are not as hard and vicious as holly (as anyone who has hand weeded around a holly bush will testify too). It also differs from Holly in that it grows quickly; forming a medium sized bush, and given time a small tree. Holly on the other hand is rather slow growing.

In summer the New Zealand Holly is covered by mounds of white flowers and older specimens develop a peeling, almost shaggy, bark which new growths breaks away freely.

Close up of Picture of an Olearia macrodonta shoot
Olearia macrodonta shoot

As the common name suggests it is a plant native to New Zealand and was first described by Joseph Dalton Hooker who in 1864 named it Eurybia dentata var. oblongifolia. This turned out to be incorrect and in 1884 John Gilbert Baker, working at Kew under Hooker, renamed it Olearia macrodonata. Though this is the name it is normally grown under in the UK; the New Zealand government’s own data base lists it as Olearia ×macrodonta Baker a hybrid between two species: O. ilicifolia and O. arborescens.

Though Olearia ×macrodonta is widely grow in the UK, the dwarf form Olearia macrodonta ‘Minor’ would be well worth seeking out for a court yard garden or rockery. This plant looks like a miniature version of the original, being smaller in all its parts, and it is listed in the RHS Plant Finder.

Olearia macrodonta 'Minor'
Olearia macrodonta ‘Minor’