Growing coffee in a greenhouse can be both rewarding and challenging. There are some factors to consider before beginning greenhouse production. They include: type of coffee, nutrient requirements, and environmental conditions. Each of these issues will be addressed in the sections below.
Choosing the proper type of coffee for greenhouse production is important. Different attributes belong to the two major types of coffee. Coffea arabica, known as Arabica, is used to produce the majority of the world's coffee. Robusta coffee (Coffea canephora) does not procuce a high quality beverage. The flavor is poor, and the caffine content is higher.
Ideal soil and nutrient conditions are useful in increasing plant health and berry yield. Soil should be loamy and well drained. Young plants require high levels of phosphorous, but are balanced by about the second or third year of growth. Once strong plants are developed, applications of 10-5-20 fertilizers should be added at a rate of 1500 pounds/acre (or as needed) each year. Mixes containing zinc, magnesium, and iron are necessary. Suitable hydroponic solutions can be developed by experienced growers, but commercial mixes are available for amatuers.
Coffee grows best in strict environmental contitions. Plants will not produce well, possibly not at all, unless these conditions are met. Temperatures should be between 60 and 70 degrees F with high humidity. Mist and cloud-like conditions are helpful. It is very benefical to provide plants with adequate, but diffuse light. Moderate airflow is recommended to keep plants cool and relatively dry. Rainfall (watering) should be an even 6" per month, with a peak wet season. Drier conditions are needed for ripening and harvest.
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