Weather impacts garden mum height, flowering

Growers in New England are reporting their garden mums are shorter and are flowering earlier this season. Univ. of Mass. floriculture ext. specialist Tina Smith said cool temperatures and cloudy and rainy weather have been the norm this summer. Mum flower buds initiate easily and develop rapidly, especially if plants are stressed in any way. Lack of adequate fertilizer and cool nights are causes for premature budding. Both flower bud initiation and development occur more rapidly under short days. However, temperature has a greater influence than day length on garden mum flowering. With several cool nights in a row, garden mums can initiate many buds prematurely, which results in early flowering. Short plants are a result of plants setting bud too early. Cool weather early in the growing season reduces the number of leaves formed on each shoot, thereby, resulting in plants with fewer nodes and shorter stems. Another reason for smaller, harder plants may be due to the lack of nutrients. Frequent rain made it difficult to keep plants fertilized. As a result, nutrients were leached and plants stopped growing.