Liquid sulfur, types, uses and benefits
Types of sulfur fertilizers
With over 20 different sulfur-containing fertilizers on the market, it can be a challenge for farmers to choose the best option. Farmers should speak with a local farmer or extension agent to determine how best to identify and correct deficiencies in their fields. This article will attempt to explain liquid sulfur , its types, and uses.
Liquid sulfur fertilizers
Sulfur fertilizers can be found in liquid form. Ammonium thiosulfate, potassium thiosulfate, and calcium thiosulfate are the most well-known types of liquid sulfur fertilizers.
Liquid sulfur, ammonium sulfate, thionyl sulfate
Ammonium thiosulfate solution (ATS) is a popular source of S for use in liquid fertilizers due to its solubility and compatibility with various ions. ATS fertilizer grade in its commercial form is a 60% aqueous solution by analysis (12-0-0-26S).
It is compatible in any ratio with neutral to slightly acidic phosphate-containing solutions or suspensions as well as with aqueous ammonia (NH3) and N solutions. It is not compatible with anhydrous NH3 or strong acids. Therefore, a wide range of NS, NPS and NPKS formulations are possible using this material. Ammonium thiosulfate can be applied directly by drip, sprinkler or flood irrigation.
Ammonium thiosulfate has gained attention in North America and is gaining importance in Europe due to its applicability and high S concentration in liquid formulations. Future demand for ATS is expected to continue to grow due to the overall increased recognition of S benefits and higher recommendation rates.
Liquid sulfur Potassium thiosulfate
Potassium thiosulfate and calcium thiosulfate solutions are not hazardous in terms of corrosion and control for agricultural crops and conditions that require these other nutrients in addition to S. Thiosulphates (S2O32-).
They are also well-suited to the methods used to apply fertilizer solutions. They are clear liquid fertilizers suitable for direct applications or mixing, making them versatile for farmers and fertilizer retailers.
Ingredients of liquid sulfur fertilizer
Liquid sulfur fertilizer comprises detoxified sulfur and a wetting agent and relates to a method for producing the same. The detoxified sulfur comprises sulfur, phyllite, loess, caustic soda, slaked salt and water. The wetting agent comprises caustic potash, canola oil and water.
In addition, liquid sulfur fertilizer is produced from the following steps: production of detoxified sulfur by mixing sulfur, phyllite, loess, caustic soda, odorous salt and water. Production of a wetting agent by mixing caustic potash, canola oil and water and production of liquid sulfur fertilizer by mixing detoxified sulfur and wetting agent.
The effect of liquid sulfur fertilizer on plant growth
Liquid sulfur is 100% water soluble and is immediately available to the plant through foliar feeding. It can be used to correct sulfur deficiency as indicated by leaf tissue analysis or visual inspection. Some indicators of sulfur deficiency are stunted growth, interveinal chlorosis, and new growth turning pale yellow while old growth remains green.
No living organism, large or small, can survive without a constant supply of sulfur. It is considered a vital secondary nutrient. In the case of plants, it is needed for at least two major reasons: it is an enzyme activator that the plant needs for nitrogen fixation, and it is essential for protein synthesis.
Most low-sulfur soils tend to be low in organic matter, coarse-textured, and likely to have a high pH. It is essential that plants be supplied with sulfur throughout the growing season.
Liquid sulfur is a highly concentrated product derived from ammonium sulfate and contains significant nitrogen. Care must be taken not to apply too much, however, as too much can cause burns.
Amount of liquid sulfur fertilizer used
- Bare Soil: Use 1-2 gallons with plenty of water per acre before planting. Incorporate into the top 1-2 inches. Apply when soil sulfur levels are low.
- Lawns: Use at 2-3 ounces per gallon of water and water sparingly. Do not use when the lawn is under heat or drought stress.
- Foliar Spray: Mist undersides and bottoms of leaves. Moisten only to runoff stage. A good spreader label will increase absorption and effectiveness. Do not use foliar feeding on flowering plants with this product. Nitrogen and sulfur content can burn leaves and flowers.
- Row crops: Mix 1-2 cups of liquid sulfur per acre using at least 15 gallons of water.
- Home gardens: Use with a pump or any type of pressurized sprayer that can produce a fine spray. Use a maximum of 2 ounces per gallon of water.
- Tree crops: Mix 2-3 liters of liquid sulfur with at least 100 gallons of water per acre.
Applications should be repeated monthly throughout the growing season or as testing indicates.
Uses of liquid sulfur
85% of the original sulfur removed by HDS is used in the production of sulfur dioxide (SO2). The primary use of sulfur dioxide is in the production of the final product sulfuric acid (H2SO4), one of the most important raw materials in the chemical industry.
Another major use of sulfur is in pesticides:
“Currently, sulfur is registered by the EPA for use as an insecticide, fungicide, and rodenticide in several hundred food and feed additives, ornamentals, turf, and residential applications. Sulfur is actually used in dust, granular, or liquid form and is an active ingredient in nearly 300 pesticide products.”
Sulfur has been known and used as a pesticide since very early times and has been registered for pesticide use in the UK since 1920.