What is SuperCal SO4?
SuperCal SO4 is a safe, natural, chemical-free product formulated to improve soil health and strengthen plants and turf. Made of 95% pure calcium sulfate dihydrite, it is finely ground and mixed with an organic bio-polymer to form a pellet. SO4 has 21% calcium and 17.5% sulfur (in sulfate form). SO4 is OMRI-listed and does not require any special licenses to apply, posting of warning signs, or re-entry intervals.
Read a testimonial about how well SO4 works at one golf course.
Pellet size
SO4 Ultra Greens Grade is for application on golf greens. Because of the micro prill, this product can be spread at any time of the day without interrupting play.
SO4 Fairway Grade is designed for application on fairways and tee boxes. This is a regular fertilizer-grade product, designed for broadcast applications and mixing with other products.
Benefits of SO4
- Amends and reclaims soils high in destructive magnesium. Magnesium has the opposite effect of calcium in soils; it destroys soil structure and reduces water, air movement and root growth.
- Improves soil structure by loosening compacted soils.
- Increases rooting depth.
- Enhances water use efficiency. 25-100% more water is available in SO4 treated soils vs. untreated soils; less irrigation water is required.
- Helps with high bicarbonate irrigation water. Bicarbonates form free lime when water evaporates, resulting in less available calcium and increased soil pH. The reduction of available calcium also leads to a loss of soil structure and reduced water infiltration.
- Decreases pH of sodic soils, and leaches sodium from soils.
- Replaces harmful salts with calcium. Sodium, chlorine and many other salts are often present at higher levels in effluent irrigation water. These salts are detrimental to plant growth and development since they rupture and destroy plant cells.
How does SO4 work?
SO4 works by leaching sodium salts and increasing soluble salts. This increases water infiltration into the soil. SO4 stimulates soil biology to breakdown thatch layers. In addition SO4 provides calcium and sulfur to turf, two important and often overlooked nutrients
With field turf, a dense thatch layer, surface crusts, or hydrophobic layers can severely reduce water infiltration rates. Unlike soil profile characteristics, these surface conditions can be readily corrected through cultivation, soil amendments or wetting agents. SO4 works to reduce surface crusting by moderating soluble salts. SO4 increases biological activity to break down thatch layers into stable carbon, reducing hydrophobic black layer formation.
Where thatch accumulation is excessive, significant amounts of irrigation water may be required just to wet the thatch layer. Evaporation losses are considerably higher from thatch than from soil. A heavily thatched turf is usually shallow-rooted, which also prevents effective utilization of irrigation water. When root systems are restricted to the thatch layer, light and frequent applications of water are needed to reduce runoff. This type of irrigation increases compaction, reduces soil oxygen, and increases disease.
The rate of movement of water into a soil is called the infiltration rate. Soils that have high sodium, low or high soluble salts, dense thatch layers, compaction, or hydrophobic black layers have poor infiltration rates. SO4 regulates soluble salts and leaches sodium, increases biological activity, and oxygen levels in soil, increasing water infiltration.
SO4 works by separating organic matter from clay soil particles making more pore space in soils. Soils consist of solid particles and pore spaces which are filled with either air or water. Pore space should account for 40 – 50% of soil, depending on texture, structure, degree of compaction, and other variables. SO4 alone does not break up compaction but can help to reduce its formation.
Depth of rooting is the most important factor in the drought resistance of a turf. A shallow-rooted turf is much more susceptible to drought injury than a deep-rooted turf. Close mowing, over-watering, excessive fertilization, soil compaction, and thatch accumulation all lead to shallow-rooted turf. The calcium and sulfur in SO4 works down into the soil profile increasing pore space and nutrients throughout the soil. This allows turf roots to grow deeper into the soil, reducing the need for frequent inefficient watering.
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Applying SO4
Soil samples should be obtained before any lime or fertilizer application. SO4 can be applied at anytime during the growing season. Best results are obtained when it is applied in the spring as grass breaks dormancy and in the fall as a winterizer.
SO4 Ultra Greens Grade is best applied using a drop spreader. SO4 Fairway Grade is easy to apply with either a drop spreader or a spinner spreader. Uniform coverage is important to avoid streaks or uneven turf color and growth. Since SO4 is pelletized, it spreads evenly with no dust, drift, or mess. SO4 is safe to use! It is non-toxic to humans and animals, doesn’t burn grass and will not cause pollution problems!
How much to apply
The amount of SO4 required will vary with the soil type. Standard application rates are:
- Ultra Greens Grade - 4#/1000 sq feet in spring and fall
- SO4 Fairway Grade - 10#/1000 sq feet in spring and fall
For sodium remediation consult your soil sample for rates.