Laurel is a popular evergreen used for screening and hedging, known for its glossy foliage and rapid growth habit. Since it never truly enters the deep dormancy cycle of deciduous trees, the proper time for cutting can be confusing. While many gardeners seek to use the winter months for tidying, pruning an evergreen during this season carries specific risks. This guide explores the feasibility of winter pruning and outlines the optimal methods based on the specific type of laurel you are cultivating.
Is Winter Pruning Advisable
Major pruning or heavy shaping of laurel during winter is generally not advised for plants in cold climates. Cold temperatures and frost can severely damage fresh cuts. Wounds inflicted during winter heal extremely slowly or not at all because the plant’s metabolic processes are dramatically slowed down.
This slow healing leaves the plant vulnerable to a phenomenon known as dieback, where the tissue around the cut surface desiccates or succumbs to infection. The unhealed wood can permit the entry of pathogens or be killed by subsequent hard freezes. Therefore, any significant reduction in size should be postponed until the plant is actively growing.
A light maintenance trim is often acceptable during the dormant period. This includes the removal of dead, diseased, or broken branches, which should be taken out whenever they are observed. This selective cut is for plant health and does not constitute the heavy shaping that carries the greatest frost risk.
The risk of winter pruning increases exponentially with the severity of the cut and the harshness of the local climate. While a mild winter might allow for a very light trim, it is safest to limit winter activity to sanitation. A heavy cut exposes the plant’s internal structure, and the resulting injury remains open and susceptible to cold damage for months.
Pruning Requirements Based on Laurel Variety
The term “laurel” encompasses several species whose individual cold tolerances dictate the risk associated with winter pruning. The most common varieties are the Cherry Laurel (Prunus laurocerasus), the Portuguese Laurel (Prunus lusitanica), and the Bay Laurel (Laurus nobilis).
The Cherry Laurel is robust and fast-growing, tolerating hard cutting when performed correctly. A major winter cut can cause sap bleeding, and the exposed wounds are susceptible to frost and fungal infection. For aesthetics, many gardeners use secateurs to remove whole leaves instead of hedge shears, which slice the broad foliage and leave unsightly brown edges.
Portuguese Laurel is slightly hardier than the Cherry Laurel, though it is slower growing. While it handles hard pruning for rejuvenation, cold season cutting remains risky, especially in marginal climates. Major shaping should occur in warmer months to capitalize on its vigorous recovery and dense growth habit.
Bay Laurel is the least hardy and is often container-grown in cold regions for indoor winter protection. This species is highly sensitive to frost damage, so winter pruning is strongly discouraged unless the plant is fully protected. Shaping should be timed for late spring to ensure new growth matures before the next cold season.
Optimal Timing and Techniques for Shaping
The optimal time for substantial shaping or reduction is late spring or early summer. Pruning then, typically after the first flush of growth and flowering, allows the plant to heal quickly. This timing ensures that subsequent new growth has the entire summer to harden off before the arrival of winter.
Formal Hedge Maintenance
For formal hedges, shearing is commonly employed using hedge trimmers. This method is fast and creates a neat, clean line ideal for boundary screens. However, it results in cut leaves that may temporarily turn brown at the edges. To promote a denser, more natural appearance, some prefer selective pruning using secateurs, removing individual stems back to a healthy bud or side branch.
Rejuvenation and Reduction
When a laurel is overgrown, a rejuvenation or reduction cut is necessary, using loppers or a pruning saw for thicker branches. For severe cuts, remove no more than one-third of the plant’s overall size in a single year. This conservative approach prevents excessive stress and allows the shrub to recover its foliage density gradually.
Selective pruning encourages growth from lower buds and inner branches, helping to maintain a full, healthy profile. Cuts should be made at a 45-degree angle, just above an outward-facing bud or side branch, which directs the plant to fill out and remain vigorous. For severely overgrown specimens, hard pruning can be staggered over two or three years to minimize shock and ensure complete recovery.