Shade cloth agriculture is a technique in which you suspend a knit or woven cloth over crops to protect them from the sun and other environmental factors [4]. Shade cloth is commonly used in arid regions, similar to the Navajo Nation, as it helps protect against the environmental dangers associated with those climates (I.E. wind, drought, heat, UV rays).
Shade cloth agriculture has many advantages especially when you consider its simplicity. The shade provided by the cloth or net blocks harmful UV radiation from the sun [1]. While the amount of shade needed will depend on the crop and climate, there are a variety of shade cloth thickness and structures to tailor your setup to your situation [4].
The increased shade also helps regulate the temperature of the area where your crops are growing and you are working. The use of shading during the hottest hours of the day can reduce the air temperature around the crops reducing their transpiration rate [5]. Some farms have had success using mobile shading systems that provide shade at some times and remove it at others to minimize transpiration while maintaining photosynthesis rates [5]. Shade cloths have been found to be especially useful in greenhouses, where hot temperatures cause unnecessary water loss [5]. Simply implementing shading can lower greenhouse temperatures, subsequently lowering evaporation rates and plant transpiration rates [5]. A study tracking water efficiency with relation to shade cloth usage for cucumbers grown in greenhouses found that mobile shading can increase water efficiency by 62% [5].
Farmers have found non-heat related benefits to implementing shade cloth/shade net agriculture. In particular, farmers in South Africa use shade nets to protect against wind, pests, and diseases [4]. The wind protection in particular would be valuable in protecting plants and greenhouses from the winds and wind-blown sands of the Navajo Nation. Similar nets are used around baseball fields to block the wind, and could prove very useful for agriculture.
As with anything, shade cloth agriculture has its drawbacks. Obviously shade cloth and the materials needed to implement it cost time and money, adding an economic barrier to its usage. Additionally most shade cloths and nets are made of plastic, a non-biodegradable material that usually ends up in landfills or the ocean [3].
Approximate Unit Cost of Various Shade Cloth Structures
- Individual Row Shading: $211.30 for a 100 ft. long row + $45 of tools [1]
- Small Field Shading (T-Post Structure): $567.03 for a 40×40 square foot field + $75 of tools [1]
- High Tunnel Shading: $233.76 for a 14 feet wide by 7 feet tall by 42 feet long tunnel + $100 of tools [1]
- Shade Cloth (No Structure): ranges from $0.20-$0.50 per square foot [2]
Finally, here is a helpful guide for implementing shade cloth structures: Constructing Shade Structures: Small Area Vegetable and Fruit Production [1]
Individual Row Shading[1] Small Field Shading[1] High Tunnel Shading[1]
Works Cited:
[1] Trost, D., & Maughan, T. (2018, September 1). Constructing Shade Structures: Small Area Vegetable and Fruit Production. DigitalCommons@USU. Retrieved November 29, 2022, from https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=2930&context=extension_curall
[2] Shade Cloth Fabric – Landscape and Hardscape. (n.d.). Agriculture Solutions. Retrieved November 29, 2022, from https://www.agriculturesolutions.com/landscape-and-hardscape/shade-cloth-fabric
[3] Chen, A. (2018, October 21). Understand shade cloth & how its colour impacts plants’ growth. C-Mac Industries. Retrieved November 29, 2022, from https://www.cmac.com.au/blog/understand-shade-cloth-colour-impact-plant-growth
[4] Agricultural Shade Netting in South Africa. (2022, April 18). AGRIFOODSA.INFO. Retrieved November 29, 2022, from https://agrifoodsa.info/news/agricultural-shade-netting-south-africa
[5] Parbst, K. (2011, September 1). Increase Water Use Efficiency with Shading. Greenhouse Management. Retrieved November 29, 2022, from https://www.greenhousemag.com/article/gm0911-selective-shading-water-efficiency-greenhouse/