umpeenkasvu

umpeenkasvu is a Finnish horticultural term describing the regrowth of shoots on the upper parts of a plant after pruning or damage, often leading to increased height and a denser crown. The phrase translates roughly to “upper growth” and is used in Finnish guides and discussions of plant training and pruning.

The concept is most relevant when management aims to control plant shape and size. It is influenced by the plant’s hormonal balance, particularly the release of apical dominance after the apical bud is removed or damaged. Carbohydrate reserves stored in roots and stems, as well as light conditions and temperature, can also affect how vigorously upper shoots regrow.

In practice, umpeenkasvu can have both positive and negative consequences. For some training systems, rapid upper growth allows rapid establishment or renewal of a hedge or canopy. In other cases, it can lead to excessive height, shading of lower branches, or reduced fruiting in fruit trees. The tendency for upper shoots to grow vigorously can also increase susceptibility to wind damage if the canopy becomes too top-heavy.

Management typically involves timely pruning to control the angle, length, and direction of new shoots, and to balance vigor between the upper and lower parts of the plant. Training strategies may combine selective pruning, spacing of shoots, and adjustments in light exposure to shape the plant and maintain health and productivity.

See also: apical dominance, pruning, shoot growth, plant training.