Solar Guard

Solar Guard FAQ

Solar Guard is a foliar spray that forms a transparent, protective coating on leaves. It uses SMART CAL++ nano-calcium technology to reduce heat stress, save water, and boost yields without blocking sunlight.

It scatters and redirects sunlight, reflecting harmful UV and infrared heat while letting in the wavelength’s plants need for photosynthesis. This keeps leaves cooler and crops growing during stressful conditions. Visit our How Solar Guard Works page to learn more.

No — unlike clay or sunscreen-type sprays, Solar Guard doesn’t block sunlight. It redirects light to increase the usable surface of the leaf for photosynthesis.

By lowering leaf temperature, Solar Guard reduces transpiration (water loss). University trials have shown 5–45% improvements in water use efficiency (WUE), even during extreme heat or irrigation loss.

Typically 14–21 days depending on weather and crop conditions. The cloaked nano-particles adhere to leaves, making the product longer-lasting than traditional sprays.
Best applied before periods of heat or drought stress, and at times when plants are using the most water (flowering, fruit set, pod development).
Yes, Solar Guard is compatible with most fungicides, insecticides, and foliar feeds. Avoid mixing with phosphate fertilizers, silicas, or acid-based products. Always do a jar test first. Download our Compatibility Chart to learn more.
It can leave a fine coating of calcium mineral on leaves or fruit, but this can be removed with acidified water (pH 3.5–5.0). To avoid residue on fresh-market crops, apply before coloring or market-ready stages.
Yes — Solar Guard can be applied by drone, tractor sprayer, or backpack sprayer, as long as even canopy coverage is achieved.
Solar Guard can be used on a wide range of crops including row crops, orchards, and specialty fruit. The only restriction is Christmas trees in the year of harvest.
Solar Guard is available in 4, 110, 220, and 250 gallon containers — designed for everything from small farms to large-scale distribution.
Traditional sprays use large particles that block light and absorb heat. Solar Guard uses nano-calcium particles that redirect light, keep photosynthesis active, and last longer on the leaf surface.

University and USDA trials have shown 5–45% improvements in drought resistance. Farmers consistently report cooler leaves, reduced stress, and stronger yields compared to untreated fields. 

Since 1999, Solar Guard has gone through 7–8 major improvements, each one increasing performance and ease of use.
Yes — Solar Guard is proudly manufactured in the USA, ensuring consistent quality and reliability for growers.
It’s Solar Guard’s patented nano-calcium formulation. The particles are 1,000x smaller than standard sprays and engineered to scatter light, reduce heat, and improve plant efficiency.
By reducing stress hours each day, plants spend more time photosynthesizing and less time shut down. This translates into healthier crops, better quality, and higher yields.
Yes — Solar Guard reduces water loss, lowers the need for reapplications, and helps farmers use resources more efficiently, supporting sustainable agriculture.
Solar Guard was developed by innovators working with Oregon State University, USDA, and industry engineers. It is distributed by Willamette Ag and backed by decades of research.

Because it’s not just a sunscreen or coating — it’s a smart, science-backed technology that keeps plants growing through stress. It combines protection, water savings, and yield benefits in one product.

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