The question of whether a blueberry bush will spread in your garden is common, and the answer depends entirely on the variety. Blueberries are perennial shrubs, but their growth habit is often misunderstood because different species behave in fundamentally different ways. Identifying the specific type you have planted determines whether you will see a tall, self-contained bush or a low, spreading patch of plants.
The Core Difference Between Blueberry Varieties
The two primary types of blueberries relevant to home gardeners are Highbush and Lowbush varieties, and their botanical structure dictates their spread. Highbush blueberries (Vaccinium corymbosum) are the most commonly cultivated type, known for the large, sweet berries typically found in grocery stores. Lowbush blueberries (Vaccinium angustifolium), often called “wild” blueberries, are much shorter plants with smaller, intensely flavored fruit. They are frequently used in commercial production in colder regions and are sometimes planted in home gardens as a groundcover.
Growth Habit of Highbush Blueberries
Highbush blueberries have an upright, clumping growth pattern, forming a multistemmed shrub that can reach between six and twelve feet tall. The plant expands vertically, forming a dense cluster of canes emerging from a centralized crown near the soil line. They are considered crown-forming shrubs, meaning their expansion is primarily outward from the center. Highbush varieties do not spread via aggressive underground runners. While they may produce new stems (suckers), these shoots typically emerge very close to the original plant’s base, ensuring the bush remains a distinct, contained plant.
Understanding Lowbush Blueberry Spreading
Lowbush blueberries are the varieties responsible for the belief that blueberry bushes spread aggressively. These plants grow much shorter, typically reaching only six to twenty-four inches in height, but they expand widely across the ground. They achieve this spread through a specialized structure called a rhizome, which is a horizontal, underground stem. Rhizomes grow outward beneath the soil surface, periodically sending up new, genetically identical shoots some distance from the original plant. This process creates dense, wide-ranging mats or colonies that can stretch many feet over time, making Lowbush varieties an excellent choice for groundcover.
Managing and Encouraging New Growth
Managing the spread of Lowbush varieties often involves physical barriers or regular pruning of the edges. Home gardeners can contain rhizomes by mowing the edges of the patch or installing a root barrier, such as plastic or metal edging. Lowbush patches are also commonly rejuvenated by mowing or burning the entire area every two to three years, which encourages vigorous new shoot growth and better fruit production. Highbush varieties are managed through targeted pruning to encourage renewal from the crown. Gardeners should remove the oldest, least productive canes close to the ground to stimulate the growth of new, fruitful stems.
New Highbush plants are typically propagated through hardwood or softwood cuttings taken from the existing shrub. Lowbush varieties can be intentionally spread by transplanting segments of the rhizomes, which will root and form a new, independent colony.