COLD POTTED CROPS
Subject:
Illinois State Florists' Association
Abstract:
For many years, energy has been a very small part of our production costs so we aimed to grow highquality crops as fast as possible, often using 60°, 65°, and even 68°-70°F night temperatures for that pur pose. But energy has become much more expensive and growers are asking about cold crops or even con sidering closing down greenhouses during the winter months. In this discussion, I consider 50° and 55°F night temperatures (NT) to be cold, with day temperatures (DT) about 10°-15° higher. (Except where specially noted, the temperatures are degrees Fahrenheit night temperature.) WHY GROW CROPS COLD? 1. ENERGY CONSERVATION. Probably the No. 1 reason for cold crops is to save energy, because of escalating cost and potential restricted supply. In OARDC Spec. Circ. 104, "Management Practices to Conserve Energy in Ohio Greenhouses," Hugh Poole and Phillip Badger state that, for a year-round greenhouse operation, lowering the night temperature reduces annual fuel consumption by approximately 3% for each degree. With a heating cost of $100,000 per year, reducing the night temperature from 60° to 55° should save $15,000, and with 50°, the savings would be $30,000
Source: • Illinois State Florists' Association Bulletin # 399
Keywords: ENERGY CONSERVATION temperatures Cyclamen production Kalanchoe production Hybrid seed geraniums
Libraries: Floriculture