12 Thing To Consider When Selecting Greenhouse Site - Expansion, Labour & Management Residence

10. Capability of Expansion – Purchase more land than you anticipate using in the beginning so that you have the ability to expand your operation. Locate the initial greenhouses such that future expansion will utilize the land area most efficiently.

11. Availability of Labor – The grower needs people who will want to work as laborers and who are “trainable” to become a retainable workforce.
*Such skills included pruning/training the plants and harvesting/packing the fruit.
*SPECIALTY LABOR will include people with additional training in such fields as plant production, plant nutrition, plant protection (insects and diseases) computers, labor management, marketing, etc. These may or may not be part of the regular workers, but could be call on as consultants as needed.

12. Management residence – The grower/manager residences should be close to the
greenhouse so that they can get to the greenhouse quickly in case of emergencies.

12 Things To Consider When Selecting Greenhouse Site - Pest Pressure & Level and Stable Ground

5. Pest Pressure – Choose a site away from existing agriculture production areas which could harbor insect pests in the fields. Insect pests of concern include white flies, aphids, spider mites and thrips (see here for pests and control methods).

6. Level and Stable Ground – The ground upon which the greenhouse will sit must be

• Graded for routing surface water to a drainage system or a holding pond. (Typical grade = ½ % or a 6 inch drop over a distance of 100 feet.)
• Compacted such that there will be no settling of the site after the greenhouse has been constructed.

12 THINGS TO CONSIDER WHEN SELECTING A GREENHOUSE SITE: Solar Radiation & Water Supply

Selecting a “good” site for the location of a greenhouse is crucial. But what constitutes a “good” site? There are several things that should and must be considered in order to increase the
chances of a successful operation and business.
12 THINGS TO CONSIDER WHEN SELECTING A GREENHOUSE SITE:
1) Solar Radiation – Plants require sunlight in order to perform photosynthesis. When plants experience cloudy days their photosynthetic rates, and therefore their ability to grow and yield a product, such as tomatoes, cucumbers, peppers, etc., will be reduced. Therefore, a region and location with high light intensity year-round is desired.

2) Water – Water quantity and quality is crucial. Water will be needed for irrigation (maximum of 1 gal/plant/day for tomatoes). Water will be needed for the evaporative cooling system and can equal or exceed the irrigation water amounts (10,000 – 15,000 gal/acre/day). In the past, excess irrigation and bleed-off water from the evaporative cooling system was allowed to “run off” onto the ground adjacent to the greenhouse (with a rec. minimum percolation rate into the soil of 1”/hr.).
*HOWEVER, due to more strict regulations and a desire to avoid ground water contamination with high concentrations of salts, large greenhouses are now recirculating the nutrient solution.
*THEREFORE, excess nutrient solution should be recycled and/or mixed with the cooler bleed-off water and redirected onto designated areas, such as grass, shrubs, trees/windbreaks, etc.
*No matter what the source of the water, a water analysis should be done.
*Note: Sea water = 32,000 ppm (mg/l) VS Tucson water = 200-400 ppm.
Note: 640 ppm TDS (total dissolved solids) = 1 mmhos/cm or 1 mS/cm.

*Desired salt levels in the source water:
SO4 < 240 ppm_____ Cl < 140 ppm___ Non-Fertilizer Salts
Ca < 120 ppm______ Fe < 5 ppm_____ Na <50 ppm
Mg < 24 ppm_______Zn < 5 ppm_____Al < 5 ppm
K < 10 ppm________Mn < 2 ppm_____F < 1 ppm
P < 5 ppm_________B < 0.8 ppm
NO3 < 5 ppm_______Cu < 0.2 ppm
Mo <>