When to prune trees

The general rule: the dormant season

For most trees the most suitable time is the dormant season — from late autumn to early spring, roughly from leaf fall until the buds swell. The reasons are practical, not theoretical:

• There are no leaves, and the structure of the tree is visible. In winter you can see which branches cross, where there is a weak union, where the deadwood is. In summer all of that is under the foliage, and pruning is done partly blind.
• The tree is not growing. During dormancy it is not spending resources, and the cut goes into healing mode as soon as the growing season begins.
• Frozen ground. This is an underrated argument. Machinery can be driven over frozen ground without churning up the lawn or compacting the root zone. That same access in March, when the ground is thawing, leaves ruts that then have to be made good.

If someone wants one general answer with no detail, it is: late winter. But for some species that is not right, which is why it is worth reading on.

Birch and maple — never in spring

Birch, maple and some other species have a strong flow of sap in spring. If a cut is made at that time, sap runs from it literally — sometimes for weeks. This is not just unsightly: the tree loses a significant quantity of its stored resources at precisely the moment they are most needed for coming into leaf, and a wet cut surface is a poor environment for a wound to close.

For these species the right time is late summer or autumn, once the flow has stopped and the leaves are still working. In practice that means the birch in your yard should not be pruned in April, even if that is the only free weekend you have. We have gathered more on birch and the particularities of other species under tree species.

Stone fruit — plums and cherries — in summer

Plums, cherries and other stone fruit are an exception to the winter rule for the opposite reason. Winter cuts on them stay open at a time when the tree cannot respond, and that is exactly what several of the typical diseases of these species are waiting for. The result is gummosis, dieback in the branches and sometimes the loss of the whole tree.

So stone fruit is cut in summer, in warm dry weather, when the tree is growing and the wound closes quickly. After the harvest or in midsummer — both work, as long as it is not a wet spell.

Apples and pears — in the dormant season

For apples and pears the winter dormant season is the right time, and it is also the easiest work of all: the crown is visible, and you can decide calmly what to keep. Late winter and early spring before the buds swell is the standard window. If a tree has gone unmanaged for years and become overgrown, it must not be put right in one go — taking out too much provokes an enormous number of weak watershoots. That is a job of two or three years. More on this under fruit tree pruning.

Summer pruning as a tool

Summer pruning is not simply "when there was no time in winter". It works differently, and sometimes that is precisely why it is the right choice.

This is useful when a tree has become too large for the place it grows in. A winter cut works against you in that case: the tree responds with rapid growth, and after two years it is back where it was. If the aim is to let light into the garden, summer is also the more logical choice — that is when you can see where the shade actually falls. Separately on that: pruning for more light.

What is not a question of season

Two things never wait for the calendar.

Deadwood. Dead branches can be removed at any time of year — they are no longer part of the living tree, and the cut affects nothing. The wood of a dead tree is brittle and breaks unpredictably, so a large dead branch over a path or a parking space does not have to be left until winter: deadwood removal.

The bird nesting season

In spring and early summer birds nest, and this is a real restriction, not a matter of politeness. In practice it means that non-urgent crown work is scheduled for later in this period, and before any work the tree is checked for occupied nests. If there is a nest, the work is postponed. The exception is the same as before — a real danger to people or buildings. This is one of the reasons why planned tree care is worth arranging in winter rather than in May: in winter there is nothing to wait for.

What not to do

• Do not cut in hard frost. Deeply frozen wood is brittle, the cut is ragged and the bark around it splits. Wait for a day a few degrees warmer — in winter there are such days.
• Do not cut in the hottest, driest part of the summer. The tree is already under stress then, and removing a large part of the crown exposes branches and trunk that have never been in the sun. The consequence is bark scorch.
• Do not prune a recently transplanted tree in the hope of helping it. This is a widespread but mistaken piece of advice. After transplanting a tree needs its leaves in order to rebuild its roots.
• Do not shorten the crown by cutting off all the ends. That is not pruning, and it solves neither size nor safety. The right job is crown thinning or controlled reduction.

What the costs depend on

The price is set by the height and species of the tree, the amount of crown that has to be touched, whether the work can be done from the ground or we have to climb or use a platform, how close buildings and cables are, what the vehicle access is like and how much brushwood has to be taken away. We chip the brushwood and take it away. Winter work over frozen ground is sometimes simpler precisely because of access. We have put the list of factors together on the prices page.

The short answer

If you do not know and do not want to go into detail: for most trees in Latvia the safest answer is late winter. Birch and maple — in late summer or autumn. Plums and cherries — in summer. And a dangerous tree is the exception that waits for none of these dates.