Boxwood (Buxus species) is a popular landscape shrub. Propagating boxwood from cuttings is the most reliable method for home gardeners to expand a collection or replace older plants without purchasing new stock. This technique is cost-effective and creates new plants that are genetically identical to the parent shrub, ensuring desired characteristics are maintained. The process involves taking small sections of the parent plant and encouraging them to develop root systems.
Why Cuttings Are the Best Method
Propagating boxwood through stem cuttings offers advantages over methods like starting from seed or using ground layering. Seeds often produce plants with variable characteristics, and the germination process can be slow and unpredictable. Cuttings ensure the new plant is a clone, maintaining the exact size, shape, and color of the source material.
The optimal time to take cuttings is during late summer or early fall (August through October), when the wood has reached the “semi-hardwood” stage. The stems are mature enough to survive separation but young enough to readily form new roots. Success requires sharp, sterilized bypass pruners, a container filled with a sterile rooting medium, and a powdered or liquid rooting hormone.
Step-by-Step Guide to Taking and Rooting Cuttings
The process begins with selecting material from a healthy boxwood shrub. Look for stems four to six inches in length and about the thickness of a pencil, avoiding overly soft new growth or very old, woody stems. The chosen stem should be cut just below a leaf node, as this area contains a higher concentration of growth hormones that facilitate root development.
Once the cutting is taken, the lower half of the leaves must be stripped away to expose the nodes and prevent the foliage from rotting in the moist rooting medium. Some propagators also lightly scrape the bark at the base of the stem to expose the cambium layer, which encourages root formation. This preparation directs the plant’s energy toward root production rather than maintaining foliage.
The prepared base of the cutting should then be dipped into a rooting hormone to stimulate cell division and root initiation. After dipping, gently tap off any excess powder or liquid before inserting the cutting into the rooting medium. A mixture of peat moss and perlite or coarse sand provides an ideal sterile and well-draining environment, preventing fungal issues while retaining moisture.
The cutting should be inserted deep enough so that the stripped nodes are buried beneath the surface, ensuring good contact with the medium. Multiple cuttings can be placed in the same container, provided they do not touch, which maintains air circulation and reduces disease risk. Immediately after planting, the medium should be thoroughly watered to settle the soil around the base of the cutting.
Caring for Your New Boxwood Plants
After planting, the focus shifts to maintaining an environment that encourages root growth. High humidity prevents the remaining foliage from drying out before roots form, often achieved by covering the container with a clear plastic dome or bag. The cuttings should be placed in a location that receives bright, indirect light, avoiding direct sunlight which can scorch the leaves.
The rooting medium must be kept consistently moist but never waterlogged, as excessive saturation can lead to stem rot. Boxwood cuttings begin to form roots within six to ten weeks, though the process can take longer depending on temperature and species. A gentle tug on the cutting will reveal resistance once a root system has developed, indicating successful establishment.
Before moving the new plants outdoors permanently, they must undergo a process called “hardening off,” which involves gradually exposing them to lower humidity and direct sunlight over a period of several days. Once hardened off and fully rooted, the new boxwood plants can be transplanted into individual pots or directly into the garden the following spring, allowing them to establish themselves before the stress of winter.