Arborvitae, a popular evergreen, is a common sight in many landscapes, valued for its dense foliage and classic form. Propagation is the process of creating new plants from existing ones. This guide explains how to multiply your arborvitae collection at home.
Why Propagate Arborvitae
Propagating arborvitae offers several advantages for the home gardener. One benefit is cost savings, as growing new plants from cuttings is more economical than purchasing mature specimens. This method also preserves specific, desirable varieties that might be difficult to find. Increasing the number of plants for landscaping projects, such as creating a privacy hedge or filling garden beds, becomes more feasible through propagation. Beyond practical benefits, nurturing new plants from cuttings offers a sense of accomplishment.
Preparing for Propagation
The optimal time to collect arborvitae cuttings is from late summer to early fall, when the current season’s growth has begun to harden but is not yet fully woody. Some varieties can be propagated in late fall or winter. Selecting a healthy, vigorous parent plant is important for successful rooting. Gather the necessary tools beforehand:
Sharp, clean pruning shears for precise cuts.
Rooting hormone (powder or gel) to increase rooting success.
A suitable rooting medium, such as sand and peat moss or sand and pine bark, for drainage and moisture retention.
Rooting trays or small pots with drainage holes, and a misting bottle or humidity dome.
Propagating Arborvitae Cuttings
Begin by selecting healthy, semi-hardwood stems from the current year’s growth. These stems should be 4 to 8 inches long, exhibiting both green foliage and a slightly woody base. Make a clean cut just below a node, a small bump or swelling on the stem where leaves or branches emerge. Some gardeners prefer a “heel” cutting, which includes a small piece of older stem attached to the base of the cutting, by gently pulling a side branch downwards until it separates from the main stem.
Prepare cuttings by removing foliage from the bottom 1 to 2 inches of the stem to prevent rot once planted. Lightly score the bark at the base of the cutting with a clean knife or your fingernail; this shallow wound encourages root development. Dip the prepared end of each cutting into rooting hormone powder or gel, ensuring the cut surface is thoroughly coated.
Create small holes in your pre-moistened rooting medium using a pencil or similar tool. Carefully insert each treated cutting into a hole, ensuring the stripped portion of the stem is fully buried. Gently firm the rooting medium around the base of each cutting to ensure good contact. After all cuttings are planted, thoroughly water the medium to settle it around the stems.
Caring for New Arborvitae Cuttings
Provide the correct environment for successful rooting.
Maintaining consistent moisture in the rooting medium is essential, but avoid overwatering, which can lead to rot. The medium should feel damp to the touch, similar to a wrung-out sponge.
Adequate humidity is also beneficial. You can achieve this by placing a clear plastic dome or bag over the cuttings, or by misting them regularly with a spray bottle. This creates a mini-greenhouse effect, reducing water loss from the leaves.
Position the cuttings in a location that receives bright, indirect light, as direct sunlight can be too intense for newly planted cuttings. Protecting them from extreme temperature fluctuations will also support their development. Rooting can take several weeks to a few months, and signs of successful rooting include new foliage growth or resistance when gently tugged.
Transplanting Young Arborvitae
Once cuttings develop a robust root system, they are ready for transplanting. This typically occurs in the spring after they have rooted over winter or in late spring to early summer if rooted in fall.
Before transplanting outdoors, harden off young plants. This process involves gradually acclimating them to outdoor conditions over several days by exposing them to increasing periods of sunlight and wind.
Choose a planting site that receives at least six hours of direct sunlight daily and has well-draining soil. Arborvitae prefer moist, loamy soil with a neutral to slightly alkaline pH.
Dig a hole that is twice as wide as the root ball and deep enough so the root collar sits at ground level. Carefully remove the rooted plant from its current container, gently loosen any circling roots, and place it in the prepared hole. Backfill with soil, gently firming it around the root ball, and water thoroughly to settle the soil.