Plant suckers are a common natural growth in gardens and landscapes. These shoots emerge from various parts of a plant, and understanding their nature is important for maintaining plant health and form. Their management is often a consideration for many plant types.
Understanding Plant Suckers
Plant suckers are vigorous, vertical growths originating from adventitious buds on the root system or lower main stem. They can also emerge from below a graft union on grafted plants. Suckering is a form of asexual reproduction, allowing plants to regenerate and create new plants genetically identical to the parent.
Sucker growth often responds to factors like plant stress, incorrect pruning, or it can be a natural characteristic of certain species. Stress from deep planting, excessive pruning, disease, or pests can stimulate sucker production. Common plants prone to suckering include roses, fruit trees, lilacs, sumac, forsythia, dogwood, and elm. For some, like quaking aspen, suckering is the primary propagation method, forming entire groves from one tree.
Why Removing Suckers is Important
Removing suckers benefits the main plant’s overall health and vigor. These growths divert water, nutrients, and energy that would otherwise support the primary plant’s growth, flowering, or fruit production. If unchecked, suckers compete with the main plant, leading to reduced vigor and potentially smaller or fewer flowers and fruits.
Suckers also negatively affect a plant’s aesthetic appeal, making it appear untidy or detracting from its intended shape. For grafted plants, rootstock suckers below the graft union can outcompete the desired cultivar. Additionally, dense sucker growth can harbor pests or diseases by reducing airflow and creating humid conditions.
Effective Sucker Removal Techniques
The most effective approach to removing suckers involves making clean cuts as close to their origin as possible. For basal suckers emerging from the trunk or stem base, use sharp hand pruners or loppers. Position the tool flush with the main stem or trunk and make a precise cut, avoiding stubs, as stubs can stimulate new sucker growth.
For root suckers emerging from the soil, expose their origin point. Carefully remove soil around the sucker to locate its connection to the root. Once exposed, tear the sucker away from the root if small enough, which helps remove dormant buds and reduce regrowth. If pulling is not feasible, cut the sucker as close to the root as possible using sharp pruners or a small pruning saw. The optimal timing for removal is when suckers are young and tender, often in early spring or as soon as they are noticed. Prompt removal minimizes stress on the main plant.
Preventing Future Sucker Growth
Proactive strategies can minimize sucker recurrence. Proper pruning techniques are important; avoid excessive or improper cuts, like topping, which stimulate sucker growth. Generally, remove no more than one-third of a plant’s total growth at one time. Making clean cuts above a healthy bud or lateral branch, rather than leaving stubs, helps prevent new shoots.
Plant selection is another consideration. Opt for non-suckering varieties or plants grown on their own roots, as grafted plants are prone to rootstock suckers. Maintaining the plant’s overall health also helps reduce stress-induced suckering. Ensure adequate watering, appropriate fertilization, and address pest or disease issues promptly. Planting at the correct depth, with the root flare visible above the soil, can also reduce sucker formation.