Many greenhouse growers regularly use plant growth regulators
or retardants (PGRs) to elicit desirable crop responses. Those
new to using PGRs should consider their goals and several
factors prior to making applications.
The MSU Extension floriculture team was visiting growers during week 14 (first week of April) and many growers were applying plant growth regulators/retardants (PGRs). Many were applying PGRs to prevent excessive elongation because of a recent string of cold, cloudy weather. Growers benefited from the relatively sunny and record-breaking warmth of February, which pushed the growth of plants in the greenhouse, but that was followed by a series of cool, cloudy days in March and early April that prevented shipping and caused leggy
growth.
These contrasting weather conditions make it challenging to keep plants on
track for their desired finished heights. Greenhouse growers can apply one
kind of PGRs, plant growth retardants, to aggressive varieties to prevent
crops from being overgrown or unwieldy in their containers.
Click here to read the complete e-Gro Alert (PDF).