Pystykasvu

Pystykasvu, literally "upright growth," is a Finnish horticultural term describing a growth habit in which plant shoots grow predominantly vertically with limited lateral spread. The term combines pysty (upright) and kasvu (growth). In English-language horticulture the concept is usually translated as upright or erect growth habit and appears in Finnish plant-trait descriptions, cultivar notes, and nursery catalogs.

Key characteristics are tall, straight stems, relatively narrow branching, and strong apical dominance that favors vertical over horizontal shoot development. The trait is influenced by genetics and environmental factors such as light, spacing, pruning, and training. Breeders and nurseries select for upright forms when vertical display, space efficiency, or wind resistance are desired. Management includes staking, formative pruning, and seasonal shaping to emphasize vertical growth; crowding or shade can shift development toward a more spreading habit.

Applications include ornamental horticulture, forestry, and fruit-tree cultivation. Upright cultivars are common in containers and street plantings where vertical presence is valued, and in early forest stands where straight trunk development is beneficial. While pystykasvu is a Finnish descriptor, it aligns with English terms such as erect or columnar growth habit used in international literature. The term helps breeders and growers communicate growth-form expectations and select suitable cultivars for a given space and climate.

See also: growth habit, erect growth, prostrate growth.