The number of main flowering clusters, commonly called “colas,” a single plant produces is highly variable, depending on biology, genetics, and cultivation practices. A cola is the dense, terminal cluster of flowers that forms along the main stems, representing the majority of the final harvestable yield. In its natural state, a plant typically produces one large, dominant terminal cola at the top. Cultivators, however, use techniques to alter the plant’s architecture, encouraging the development of many secondary colas and significantly increasing the overall potential yield.
Understanding Apical Dominance and Cola Formation
The plant’s natural tendency to produce a single, large terminal cola is governed by apical dominance. This biological mechanism ensures the central stem, or apex, grows preferentially upward, an evolutionary strategy to outcompete neighboring plants for sunlight. The primary chemical driver is the plant hormone auxin.
Auxin is synthesized in the shoot tip and transported downward, where its high concentration near the apex actively inhibits the growth of lateral buds located further down the stem. By suppressing side branches, the plant dedicates energy and resources to the main growth point. This results in the characteristic “Christmas tree” shape, featuring one main terminal cola and small, underdeveloped side clusters.
Genetic and Environmental Drivers of Cola Quantity
The inherent number and structure of colas are first determined by the plant’s genetic blueprint. Indica strains are predisposed to a shorter, bushier structure with dense, tightly packed colas forming close to the main nodes. Conversely, Sativa strains grow taller and more slender, naturally producing loose, elongated clusters distributed along the branches.
External conditions also control secondary cola development. Light intensity is a major factor, as strong, high-intensity light that penetrates the canopy is necessary to sustain robust growth at lower branching sites. When light is weak or blocked, lower potential cola sites remain underdeveloped, often yielding low-quality, airy clusters sometimes referred to as “popcorn” buds.
Plant spacing further affects light availability and branching propensity. In a crowded environment, plants instinctively stretch upward, reinforcing apical dominance to reach the light. Ample space allows light to reach lower axillary buds, encouraging lateral growth and promoting secondary cola development along the side branches.
Methods for Increasing Secondary Cola Sites
Cultivators employ several techniques, known as training, to disrupt apical dominance and maximize the number of colas.
Topping and FIMing
Topping is a direct method involving the physical removal of the apical meristem, or main growth tip. This immediately stops the flow of auxin from the apex, causing the plant to redistribute growth hormones and energy to the two lateral branches directly beneath the cut. This effectively turns the single terminal cola into two, and the technique can be repeated to double the number of colas again. A similar, less predictable technique is FIMing, where only a partial removal of the growth tip occurs. FIMing often results in the formation of three or four new secondary colas at the cut site, though the outcome is less symmetrical than topping.
Low-Stress Training (LST)
LST achieves a similar result without cutting the plant, which minimizes recovery time. This technique involves gently bending and securing the main stem horizontally below the level of the side branches. Since the highest point is no longer the apex, the lateral branches sense they are now the highest point and begin growing upward as new colas.
Pruning Techniques
Pruning techniques like defoliation and lollipopping focus the plant’s energy specifically on productive cola sites. Defoliation involves removing excess fan leaves that block light from reaching lower buds. Lollipopping is the removal of the lowest, underdeveloped branches and leaves that will never produce a worthwhile yield. By stripping away these non-productive lower sites, the plant redirects its finite energy and resources into the remaining, well-lit clusters, increasing the size and density of the secondary colas.