Plant enthusiasts would like experts to offer species-specific pruning calendars. However, it’s not that straightforward. Gardening expert Ignacio Guío, known online as Chico Plantas (@ignacioguio), insists that pruning should not be done solely according to a pruning calendar, but according to the plant’s real condition and the local climate, the real condition of the plant and the local climate.
Even though winter has begun, if temperatures remain mild, many species continue with active sap, accumulating and moving energy internally. If large cuts are made at that time, the plant does not interpret that a rest period is near; instead it continues reacting as if it has to grow, sprout or heal with intensity. And there the problems begin.
The two safest times for strong pruning
According to Guío, the periods he generally recommends for major pruning are two very specific transitions, from winter to spring and from summer to autumn. At those times, the plant is ready to redistribute its energy without excessive stress.
Carrying out these prunings when there are still weeks of mild temperatures can produce exactly the opposite of what you want. Instead of encouraging growth, you force the plant to spend reserves at a unfavourable moment. “If you prune hard when temperatures have not properly dropped, the plant can ‘bleed out’ and be left with insufficient energy to re-sprout later,” warns Ignacio.
What happens when the sap stays highly active
One of the key concepts Ignacio explains is the so‑called “bleeding”. When you prune a plant while sap is flowing strongly, the wounds stay open and the plant begins to lose energy continuously through them.
In conifers, cypresses, pines and other similar species, this bleeding can manifest as resin. It is not just an aesthetic issue, it is energy that the plant is expelling when it should be conserving it to get through the winter.
The problem is not only the bleeding itself, but the timing. If the plant loses energy before entering the real cold period, it arrives at winter weakened, with fewer internal reserves to resist and, later, to re-sprout with strength. The result can be poor growth in spring or even prolonged decline.
Why the local climate makes all the difference
Not all areas have the same room for manoeuvre. Ignacio emphasises that in places with mild winters, such as certain southern regions, some tasks can be brought forward slightly without serious consequences. In fact, it may be advisable not to delay pruning “because otherwise the plants will start to bud,” Guío warns.
However, even in those cases, it is essential to know each species well and observe how each plant responds to the climate. It is not the same a light prune as a substantial structural prune, nor do all plants react the same to the same cut.
When pruning on a large scale, plan ahead without rushing
Hard pruning aims to direct future growth and prevent the plant from sending energy to areas that are not desirable. For this to work, you must anticipate, yes, but without rushing.
Ignacio explains that pruning too early can cause the plant to start budding ahead of time, just the opposite of what you want. That early flush will be checked by the subsequent cold, creating unnecessary stress.
Conifers and other especially sensitive species
In the case of cypress, cedar, spruce and conifers in general, Ignacio stresses extreme caution. These plants react very strongly to sap flow and to open wounds.
The same can occur with fruit trees and other woody species, where pruning out of season can upset the balance between roots, branches and internal reserves.
What to do if winter hasn’t taken hold yet
If you still have mild temperatures and you’re unsure whether to prune, opt for observation and prudence. Limit yourself, if anything, to removing dead, damaged or clearly problematic branches, and leave structural pruning for when the cold has truly set in.
This small gesture can distinguish a plant that comes through strongly into spring from one that carries unnecessary wear and tear for months. Pruning well isn’t about doing it early, but about doing it at the right moment.
