8 Espalier Tie-In Steps for Training Morello Cherries on Wire

Morello cherries, Prunus cerasus, will crop in a north-facing border where a dessert cherry would struggle to build enough sugar. The fruit is acid and mainly grown for cooking, so full dessert sweetness is not the target. The Royal Horticultural Society lists Morello as the standard self-fertile sour cherry for shaded walls in the UK.

That shade tolerance explains the flat training. A wall keeps some warmth into autumn, and the wire framework spreads the fruiting wood across a face that may receive only two to four hours of direct sun a day. Careful tying during the first few seasons takes a bare-root maiden toward a fan capable of cropping within three seasons.

Set the wire before the tree goes in

Run horizontal wires in 3mm galvanised wire, spaced 30cm apart vertically, and take the framework up to roughly 2 metres. Screw-in vine eyes with a 10mm or 12mm shank hold the wire about 5cm out from the masonry. That gap lets air move behind the foliage and helps reduce the risk of bacterial canker.

Put a straining bolt or Gripple tensioner at one end of each run. The wire has to stay taut once the tree begins pulling on it; a slack run lets the fan sag forward, and the lower tiers begin to shade themselves.

Mark and drill the wire positions before planting. Working above an established root system is awkward, and standing close to the wall compacts the planting soil. On a fence, the same 3mm wire can pass through eye bolts fixed at each post. Timber flexes more than brickwork, so tension matters even more there. A 6mm straining bolt with a turnbuckle keeps the run tight. When plucked, the finished wire should give a slight ring, with no loose twang.

Steps one to three: plant, cut back, choose the first ribs

Plant a bare-root maiden while it is dormant, between November and March. Set it 20cm clear of the wall so the roots sit outside the driest part of the rain-shadow strip. Spread the roots, firm the soil with the heel, and water the tree in even when the ground is already wet.

Cut the maiden back to around 45cm, making the cut to a bud with two strong buds below it pointing left and right. The cut forces the low branching that a fan needs.

During the first summer, pick two opposing shoots for the lowest ribs and keep a central leader. Tie each rib to a bamboo cane, then tie the cane to the wires at roughly 40 degrees from vertical. The cane protects the young wood. A fresh shoot pulled hard onto a horizontal wire can snap at the union.

Rub out shoots that grow straight into the wall or straight out from it. Those shoots do not sit in the flat plane of the fan and tear easily if forced into position.

Steps four and five: tie angle and tie material

For the structural ribs in years one and two, tie at 35 to 45 degrees from vertical. Once the wood has lignified, lower the ribs gradually toward the horizontal wires. Angle governs vigour: a vertical shoot makes extension growth and little fruit, while a shoot pulled flat too soon can stall or die back.

Use soft jute twine or 4mm plastic-coated wire ties. Bare wire against bark cuts too easily as the stem thickens.

Leave a finger-width gap between tie and stem. Cherry wood puts on girth quickly in its second and third years, and a tight tie can girdle a rib within a single season, cutting off the flow above the pinch point. Check every tie in February, then slacken or replace anything that has started to bite.

Make each tie as a figure of eight. The wire takes the strain on one side, and the stem rests in the loop on the other. By the third year, a 2-metre fan may have 30 to 40 tie points, so a 250m roll of jute costing a couple of pounds is enough for several seasons of retying.

Feed the root run, not the leaves

A Morello on a shaded wall competes with the wall footing for moisture. Feeding should keep growth steady without pushing soft, canker-prone shoots.

Comfrey liquid feed supplies potassium for fruit and avoids the nitrogen surge of a general feed. Pack a lidded bucket or water butt with Bocking 14 comfrey leaves, weigh them down, and draw off the dark liquid after three to four weeks. Dilute the concentrate at roughly 15 parts water to one part feed, until it has the colour of weak tea. Water it onto the root zone every two weeks from blossom set through to August.

In late winter, mulch the strip from the stem out to 60cm with 5cm of composted bark or garden compost. Keep the mulch 5cm clear of the bark to avoid collar rot. The mulch holds spring moisture near the roots and suppresses grass, which otherwise robs a shallow cherry root system.

On heavy ground, a Mantis tiller can work leaf mould into the soil before planting. Once the tree is in, use a fork instead. Cherry roots run close to the surface, and a tiller shreds them. Keep high-nitrogen lawn fertiliser away from the root run as well, since the lush growth it drives is the sort of soft wood bacterial canker colonises.

Steps six and seven: renew the one-year wood

Morello fruits almost entirely on shoots made during the previous summer. An apple-style spur system fails for that reason. Each year, some fruited wood has to be cut out and young replacement shoots tied in to fill the space.

Prune in spring as growth starts, or straight after harvest. Avoid the dormant winter pruning window because cold-season cuts invite silver leaf fungus, Chondrostereum purpureum, and bacterial canker.

After picking, find the shoots that carried fruit. Cut a portion of them back to a young replacement shoot near the base, then tie that replacement onto the wire. A productive fan carries a mix of this-year growth and last-year fruiting wood, without long bare stretches of old wood that have stopped cropping.

Tie the new shoots while they are still flexible in late summer. If left until they harden, they set in the wrong plane and become difficult to bring flat without damage.

By year eight or ten, the original ribs are thick and the replacement-shoot cycle has passed through them several times. Some Morello fans take a hard renovation cut back into older wood, losing a crop or two while they rebuild. Others decline gradually as the cropping wood retreats toward the tips. The outcome appears to depend more on canker load in the old wood than on the exact pruning cut, and wire training cannot remove disease already established inside a rib.

Net before blackbirds find it

Blackbirds can strip a Morello before the fruit has fully coloured. From the pink-fruit stage onward, a drape of 19mm net over the fan is the reliable defence; a Hozelock pond pump and a nearby water feature do nothing for cherries, despite claims in some forum threads.

Step eight: lower the ribs and read the fan

By the third spring, the lower ribs are woody enough to move down from their 40-degree cane angle toward the horizontal wires. Release the cane ties, ease each rib down over a week or two so the wood does not crack, and tie it to successive wires as it settles. The near-horizontal angle checks extension growth and encourages flower bud.

Watch the response along each rib. A rib with a tuft of leaves at the tip and bare wood behind it has usually been lowered too hard or starved at the root. The next season, that rib can sit a notch higher, with mulch and watering checked around the root zone.

A rib throwing strong vertical water shoots along its length is too vigorous. The usual causes are nitrogen-rich feeding or a hard winter prune. Rub those verticals out in June while they are still soft. A balanced rib carries short side shoots every few centimetres, and each one is a future fruiting position to thin and replace on the same renewal cycle.

Ribs tied too close together crowd at the wall top and shade each other. On a 2-metre-wide allocation, the ribs need to fan out so the outermost reach the edges by year four, with roughly 15cm between them at the tips. If growth reaches the top wire with spare length, it can be pruned into an arch along that wire, turning would-be vertical extension into more horizontal fruiting wood.

On north-facing borders, light is often too limited to carry much productive growth above the main framework. The upper wire may stay spare, even while the lower ribs carry a useful crop.