Growers seeking disease-resistant geraniums

"Very high on my priority list is the shape and size of individual leaves, because this is key to both disease control and plant habit," says Albert Grimm, Head Grower of Jeffery's Greenhouses in Ontario, Canada.

Click here to start slide show.

Grimm says botrytis is a saprophyte, and it needs dead or dying tissue to grow on to get a foothold in a crop. Lower leaves abandoned by the plant make an ideal location for this disease to get started. Some geranium varieties expand leaf size under low light more dramatically than others, Grimm says. Larger leaves allow less light to reach into the canopy, and this increases leaf abscission and botrytis incidence in high-density crops.

His operation is in Canada, so the geraniums are being grown at cooler temperatures and experience cool temperatures at garden centers. For this reason, Grimm looks for varieties that are cold-tolerant.

Vigor, Timing Important to Growers

Dominik Neisser of Vivero Internacional is looking for the opposite. He grows geraniums in California, so he orders heat-tolerant varieties. He says an ideal variety is even growing with the same vigor and flower timing, and most importantly, is disease-resistant.

Continue reading.

Photo created by serhii_bobyk - www.freepik.com

Source: Greenhouse Grower