6 Fruiting Spurs Trained by a Cordon System on a Braeburn Espalier

A Braeburn cordon carrying six fruiting spurs along one horizontal arm has reached a practical density for cropping. Braeburn is a spur-bearing apple, so fruit forms on short woody stubs that can remain productive for several seasons. When a horizontal cordon is trained along a taut wire, with the next tier roughly 40cm to 45cm above it, each spur can hold two to three fruits without casting too much shade across its neighbour. Push the spacing beyond six or seven spurs per 60cm of cordon and apple size begins to drop, because the leaf area available to feed each fruit falls short of what the crop needs.

The pruning year is split by about five months. Winter work sets the arm and forces the shoots that will become spurs. Summer work, delayed until the base of the new shoots has gone woody, diverts the tree away from leafy extension growth and keeps fruit close to the wire. When those jobs are swapped or blurred together, a trained apple often makes long growth while the cropping wood creeps outward.

Why July thinning earns its place

Many people cut apples in January and leave them untouched during the growing season. A restricted form such as a cordon or espalier needs attention earlier. The Royal Horticultural Society gives mid to late July as the summer pruning period for cordon and espalier apples in the UK, once the lower third of each new shoot has turned brown and stiff.

The standard cut is short. Shoots that rise directly from the cordon are shortened to three leaves above the basal cluster. Shoots growing from an established spur are shortened to one leaf above that cluster. Immature shoots stay in place until the growth has firmed.

That timing removes the active shoot tip while the season still has light to spare. The tip is where the tree concentrates much of its vegetative drive. Cut it off in July and the tree has less chance to answer with a fresh flush before winter, so more of the season’s gain remains in the fruit and in the wood already formed.

The lower buds also receive light through August. A bud exposed then is more likely to develop into a fruit bud for the following year. A shaded bud on a long, leafy extension tends to remain a growth bud.

A Braeburn cordon that has been summer-pruned well usually shows fat, rounded buds at spur bases by September. A cordon cut only in winter tends to answer with whippy regrowth, flat pointed buds, later cropping and fruit carried farther from the wire each year. The Modified Lorette System described by the RHS is this same summer discipline used repeatedly: mature shoots are shortened in stages through late summer, while soft growth waits until it has firmed up.

Make each cut cleanly, angled just above a bud and sloping away so water runs off. A bypass secateur such as a Felco 2, or the smaller Felco 6, will handle shoots up to about 20mm without crushing them. An anvil blade can mash the stem tissue and invite dieback. A sharp bypass blade leaves a clean face that calluses within a few weeks.

Building the spur system in the dormant season

Between November and early March, the leaves are gone and the framework can be seen. On a maiden cordon in its first winter, the leader is tipped by about a quarter of its length to make side shoots break along the arm. In later dormant seasons those side shoots are cut back to two or three buds, and over time they thicken into the spur system.

A spur begins as a short stub, then becomes a branched, congested cluster of fruit buds over three to five years. By the time a Braeburn cordon carries six mature spurs, several may have four or more flowering points. That is productive wood, although it can soon become too crowded for good-sized fruit.

On a fifteen-year-old Braeburn, an old spur system can carry ten or twelve flower buds where six would crop better. The tree may set fruit on nearly all of them, giving a heavy load of undersized apples one year and very little the next. This biennial swing is especially sharp on Braeburn because the variety sets fruit readily.

Dormant spur thinning reduces that congestion. The oldest and most crowded clusters are cut back with secateurs or a small pruning saw, often removing around a third of the flowering points. The remaining spurs should each have 8cm to 10cm of clear cordon around them, enough space for light and enough room for fruit to hang without rubbing.

Rootstock changes how much pressure the system will tolerate. A Braeburn on M27, the most dwarfing common apple rootstock, makes a short cordon, needs staking for life and rarely grows beyond head height. On M9 or M26 the same variety builds a larger framework and carries more spurs per metre. The RHS and UK nurseries such as Blackmoor and Keepers list M9 as the standard choice for cordons and espaliers because it crops early, stays manageable and does not produce the vigorous water shoots that a semi-vigorous stock such as MM106 often makes after hard cutting.

Where the espalier changes the work

An espalier is several horizontal cordons stacked on one trunk, usually two to four tiers spaced 40cm to 45cm apart. Each tier is trained and spur-pruned in the same manner as a single cordon, so the six-spurs-per-arm rule repeats up the tree, with the added problem of keeping the tiers equally vigorous.

The vigour gradient on a tiered tree

Apples show strong apical dominance. On a tiered espalier, the top tier usually grows harder than the bottom one. Sap flow and growth hormones favour the highest points, so upper arms thicken, extend and throw strong upright shoots. Lower arms can stay thin, and shade from the growth above can even make them die back.

The pruning has to lean against that habit. Weak lower tiers receive the harder winter cuts, since dormant pruning stimulates vigorous regrowth from the buds left below the cut. Strong upper tiers are handled more lightly in winter, with most of their restraint coming from summer thinning, which removes growth after it has spent some of its force.

The angle of an extending arm adds another control. A growing end tied down horizontally slows. Lift that same end toward the vertical and extension speeds up. During the building of an espalier, a weak lower arm can be trained at a slight upward angle for a season to add strength, then tied back to the horizontal once it has caught up.

The espaliers in the walled kitchen garden at RHS Wisley show that balance held over decades. The bottom tiers carry as much fruiting wood as the top because the pruning has been deliberately uneven from year to year. Equal cuts on every tier would favour the part of the tree that was already strongest.

Water shoots reveal the mistake quickly. These thick vertical whips erupt from the trunk and upper arms after a hard cut, and Braeburn can produce them fast. Rub them out with a thumb in May while they are soft and the tree loses almost nothing. Cutting them with secateurs in July after they have hardened works too, though it takes longer. Leave them until winter and the job becomes sawing out thumb-thick wood, often followed by three replacement shoots from the same area.

A flat, productive espalier over twenty years usually belongs to a tree that has been walked every few weeks in the growing season. Excess vigour is easiest to remove while it is still a green shoot. Once it has become wood, every correction is larger and every response from the tree is stronger.

Reading Braeburn buds before cutting

A Braeburn fruit bud is plump, rounded and proud of the wood, often sitting on a short spur. A growth bud is slimmer, more pointed and flatter against the shoot. Shortening every shoot to the same length without reading those shapes can remove much of the following season’s crop.

On an overbuilt spur, the better fruiting wood is usually the younger wood nearest the cordon. Older tips can be sacrificed first. Fruit buds on four- or five-year-old wood tend to produce smaller apples, and the fruit hangs farther from the arm. That extra distance bends the spur under weight and shades buds closer in.

Renewal means cutting the ageing tip of a spur back to a strong young fruit bud close to the wire. Done every few years, this keeps a Braeburn cordon cropping tight against the framework instead of drifting outward into a tangled shelf of old spur wood.

The awkward judgement comes when renewal has already been repeated several times. A vigorous stock may refill an arm quickly after being cut back to bare cordon, while the same cut on M27 may never fully recover. How much live wood has to remain before rebuilding a whole arm becomes the only realistic choice?