Groeiremmende

Groeiremmende is a Dutch term used to describe substances or practices that inhibit or slow down plant growth. In horticulture and agriculture, groeiremmende middelen (growth-retardants) are chemical or hormonal agents applied to crops and ornamentals to limit shoot elongation, control plant habit, and improve production efficiency. They are used to create compact, uniform plants, reduce lodging, and manage canopy size for better light penetration and harvest efficiency.

Most groeiremmende middelen act by inhibiting gibberellin biosynthesis or signaling, thereby reducing cell elongation. Others influence the balance of plant hormones such as auxin, cytokinins, or ethylene. Some compounds are systemic, absorbed and translocated within the plant, while others are contact-acting.

Common applications include ornamental shrubs, roses, chrysanthemums, grapes, fruit trees, and turfgrass. Examples of active compounds are paclobutrazol, uniconazole, chlormequat chloride (CCC), daminozide, and mepiquat chloride. Paclobutrazol and uniconazole primarily inhibit gibberellin production; CCC and daminozide affect growth by altering hormonal pathways; mepiquat chloride is widely used in cotton and other crops to reduce vegetative height.

Regulation and safety: The use of groeiremmende middelen is subject to regulatory approval in many countries, with restrictions on application timing, rates, and pre-harvest intervals (where applicable). Residue concerns and environmental effects are considered, and applications require adherence to label instructions and appropriate protective equipment for handlers.

See also: Plant growth regulator, Gibberellin antagonist, Horticultural management.