Bamboo is a type of grass, not a tree, and it is defined by its rapid growth and unique woody culms. The answer to whether this plant can be successfully cultivated in Kentucky is a definitive yes. The temperate climate of the state, which primarily falls within USDA Hardiness Zones 6b to 7b, is welcoming to many cold-hardy bamboo species. Kentucky’s conditions allow these plants to thrive, making them a popular choice for everything from privacy screens to ornamental specimens.
Kentucky’s Climate and Suitable Bamboo Types
Kentucky’s climate, characterized by warm, humid summers and mild to moderately cold winters, is well-suited for specific genera of bamboo. The state’s hardiness zones, ranging from a minimum average temperature of -5°F in the north (Zone 6b) to 5°F in the warmer southern areas (Zone 7b), require the selection of species known for their exceptional cold tolerance. Successful growth depends on choosing varieties that can withstand the lower end of this temperature spectrum.
The genus Phyllostachys contains many of the most cold-hardy running bamboos, which can survive temperatures down to -10°F to -20°F without severe damage to the rhizomes. Specific species like Phyllostachys nuda, Phyllostachys bissettii, and Phyllostachys aureosulcata (Yellow Groove Bamboo) are excellent candidates for the region. These types often maintain green foliage throughout the winter, although harsh cold or drying winds can sometimes cause leaf curl or “winter burn,” which is typically recovered from in the spring.
For growers seeking non-invasive options, the clumping genus Fargesia is also a viable choice, with varieties like Fargesia rufa and Fargesia murieliae tolerating temperatures as low as -15°F to -20°F. These varieties often prefer some afternoon shade in Kentucky’s hot summers to prevent leaf scorching. Regardless of the type selected, bamboo prefers well-drained, fertile soil and requires consistent moisture, especially during its shooting season in spring and the establishment phase.
Understanding the Difference: Running versus Clumping Bamboo
The primary distinction between bamboo types lies in the structure of their underground stems, known as rhizomes, which dictate their growth pattern. Running bamboo, classified as monopodial, spreads aggressively via long, thin, horizontal rhizomes, often called leptomorphs. These rhizomes can travel several feet away from the parent plant before sending up a new cane, or culm, leading to rapid colonization of an area.
Most of the taller, timber-type bamboos that survive Kentucky’s winters fall into this monopodial category. They rely on this aggressive underground network to store energy and survive cold temperatures.
In contrast, clumping bamboo employs sympodial rhizomes, known as pachymorphs, which are short, thick, and U-shaped. These rhizomes turn upward almost immediately to produce a new culm directly adjacent to the parent plant. This growth pattern results in a dense, contained clump that expands outward slowly, often only a few inches per year. While much less invasive, the cold-hardy clumping varieties like Fargesia tend to be smaller in stature than their running counterparts.
Necessary Strategies for Containment
Given that the most robust, cold-hardy bamboos suitable for Kentucky are typically the running types, containment is a mandatory part of cultivation. The most effective method is the installation of a physical rhizome barrier made from high-density polyethylene (HDPE). This non-porous material, ideally 60 to 80 mil thick, should be installed vertically to a depth of 24 to 30 inches.
The barrier must encircle the entire planting area. A critical step is ensuring the barrier protrudes approximately two inches above the soil line. This exposed lip prevents rhizomes from simply “jumping” over the top of the barrier and allows for easy visual inspection and removal of any stray growth.
For growers who prefer a low-cost, active maintenance approach, trenching and root pruning are viable alternatives. This involves digging a shallow trench, about six to eight inches deep, around the perimeter of the desired growing area. The trench is then routinely patrolled with a sharp spade, often twice a year during the active growing season from late summer through fall.
Another containment option is growing running bamboo successfully in above-ground containers or raised beds, provided the vessel is made of a sturdy material like metal or concrete. Container-grown bamboo requires the root ball to be thinned out or divided every few years to prevent the plant from becoming root-bound and potentially stressing the container itself.