Expanses of unadorned walls are becoming a part of our American scene. This is equally true of residential as well as business structures.
To the designer, these large unbroken areas represent today’s concept of functional design. To the builder, they mean faster production.
To the gardener, these blank walls may be considered new canvases against which they can create the most satisfying pictures or compositions with plants.
At this point, many of us think instinctively of foundation plantings.
Often these are not the best answer.
Where large areas are to be treated, plantings sufficiently heavy in interest to be in proper scale would require excessive space.
It is here that espalier plants fill the bill to perfection.
What Are Espaliers?
Espaliers are plants, which are trained by pruning and supporting into patterns on a flat plane.
In other words, they are arranged in height, spread, and branch arrangement against a wall or trellis, while their thickness is held to a minimum.
Different Ways of Espaliering
In the past, most espalier plants were trained indefinite and quite stylized shapes.
Usually, they were grown on dwarfing rootstocks.
Fruit trees especially are still so grown to a limited extent.
Much more significant to the broad scene, however, is the increasing use of plants of normal size, trained in less formal shapes.
Fan and rectangular shapes are popular, but free forms are widely used and fit many needs in today’s gardens.
One point needs to be emphasized.
It is not necessary, or even desirable in most cases, to cover the whole wall or even a large part of it.
Plan, rather, to grow and shape an interesting plant so placed on the wall as to create an interesting pattern.
The least area of growth which will produce interest where monotony was, is probably best.
Provide Methods Of Support For Espaliers
First, provide some method of support.
Free-standing trellises, either of wood or of angle iron uprights and wire laterals, have many uses.
Erect these slightly away from the wall to provide good air movement behind the plants and facilitate cultural operations.
On masonry surfaces, no special supports are needed for clinging plants such as English ivy.
Support of non-clinging plants on such walls is not difficult.
Lead anchors can be driven into holes drilled in the masonry, or more often the mortar joints.
Screw eyes or long nails are driven into these and they are connected with a grid of wires.
Ties can be made to these wires at any point.
If you prefer not to drill for anchors, you can use ceramic plugs which are glued to the stone or brick surface.
These have metal straps attached to the head which fold over the branches and hold them in place.
Branches may be fastened directly to wooden surfaces, but this system presents problems when painting time comes around.
The trellises mentioned above are better.
Iron nails with lead straps on the head are available.
Tall Evergreens Grown As Espaliers
Now, look at the plants which lend themselves to use as espaliers.
The list is longer than would seem likely at first thought.
Where considerable height is desired, the following evergreens are a few of the possibilities:
- Camellia japonica and Camellia sasanqua and their varieties (for mild climates; sun to moderate shade).
- Eriobotrya japonica, loquat (for mild climates); winter flowering; full sun
- Euonymus fortunei and varieties (wintercreeper), sun to shade; subject to scale.
- Hedera helix and varieties (ivy); sun to heavy shade.
- Ilex in variety (holly); sun to heavy shade.
- Magnolia, evergreen species; sun to moderate shade.
- Osmanthus fragrans (sweet olive); sun to moderate shade.
- Pyracanthra species and varieties (firethorn); Pyracanthra kasan is hardiest, but semi-evergreen at northern limits; sun.
Among the tall growing deciduous plants, consider:
- Campsis radicans or, better, Campsis Grandiflora (trumper creeper); sun.
- Cornus florida or Cornus kousa and varieties (flowering dogwoods); sun to light shade.
- Hibiscus syriacus and varieties (rose-of-sharon); sun.
- Hibiscus rosa-sinensis and varieties (Chinese hibiscus); won’t stand more than 10° degrees of frost; sun.
- Hydrangea petiolaris (climbing hydrangea); a neglected beauty; sun to light shade.
- Lonicera maacki (Amur honeysuckle); sun to light shade.
- Malus species and varieties (apples and especially crab apples); Malus hupehensis is one of the best; sun.
- Prunus in wide variety, including peaches, apricots, and plums, both flowering types and those grown for fruit.
- Rosa, climbing species and varieties (climbing roses); sun.
- Schizophragma hydrangeoides, are similar to climbing hydrangea and are often mixed in the trade.
- Wisteria species and varieties; are best kept away from wooden structures as they are house wreckers literally!
Medium-Tall Evergreens Grown as Espaliers
Where ultimate heights of from 4’ to 6’ or 8’ feet are needed, these evergreens work well:
- Abelia grandiflora (glossy abelia); sun to moderate shade.
- Jasminum species (jasmine); for mild climates; Jasminum nudiflorum is hardy in sheltered spots to Boston; sun or light shade.
- Ilex crenata and varieties (Japanese holly); sun to moderate shade.
- Taxus in variety (yew); sun to moderate shade.
Deciduous plants for this medium height class include:
- Buddleia species and varieties (butterfly-bush); sun.
- Chaenomeles laginaria and varieties (flowering quince); sun to fairly heavy shade.
- Cytisus species (broom); sun, alkaline soil.
- Forsythia species and varieties (golden bells); sun.
- Kerria japonica pleniflora (globe-flower); sun to light shade.
- Lonicera species (honeysuckle); sun to moderate shade.
Low Evergreens Grown As Espaliers
Not many low espaliers are made, but where foundation walls need cover, try these evergreens:
- Cotoneaster horizontalis or Cotoneaster microphylla (rock spray and small-leaved cotoneaster); sun to light shade.
- Euonymus fortunei varieties kewensis and minimus (wintercreepers); sun to heavy shade; slow-growing.
- Taxus baccata repandens and Taxus cuspidata nana (yews); sun to moderate shade.
And, finally, low growing deciduous plants include:
- Chaenomeles japonica and varieties (Japanese quince); sun to fairly heavy shade.
- Cytisus, low growing species such as Cytisus beani, (Bean’s broom); sun; alkaline soil.
- Hypericum in variety (St. Johnswort); sun to moderate shade.
The growing of these plants varies little from ordinary culture.
Fertility, however, is best kept at moderate or slightly lean levels to prevent excessive growth.
Drainage should be good or better in all cases.
Where espaliers are to be grown on newly built houses, it is wise to do the following:
- Probe the soil and remove all debris buried by the builder.
- Look especially for excess mortar left by masons when acid-requiring plants are being planted.
- Fill in with good, humusy loam.
How And When To Prune Espaliers?
Pruning is a more demanding operation with espaliers than it is with free-standing plants.
Branches should be evenly spaced and securely tied in the desired form.
Raffia or rubber budding strips make good tying material for small, tender branches.
Soft cotton twine is normally used for heavier branches.
The two major pruning periods are July and midwinter.
Excess leaders are cut out at the base.
Then side shoots are reduced in length, usually to 4 to 6 leaves.
Don’t prune spring-blooming shrubs like forsythia in the winter, or the bloom will be lost.