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5 Different On How To Apply Sul Po Mag You Must Be Looking For

Organic Sul-Po-Mag is the short name for sulfate of potash-magnesia (langbeinite). It is also known as K-Mag Natural. Langbeinite is a natural mineral that is mined from the earth. It is a white to a yellow crystalline mineral that contains 22% sulfur, 10.8% magnesium, and 21.5% soluble potash. You must know how to apply Sul po mag to see its incredible results.’

The nutrient-dense Sul-Po-Mag is a popular fertilizer. It’s especially good where it needs to provide adequate plant nutrition in regions with low magnesium, potassium, and sulfur content.

That’s because K, Mg, and S are stored within each of its particles, which help provide uniform distribution. Read on for detailed instructions on how to apply Sul po mag so that you can reap its benefits.

How To Apply Sul Po Mag 1
Sul-Po-Mag 0-0-21.5 Sulfate of Potash Magnesia – via

Sul Po Mag – An Organic Fertilizer

Sul Po Mag is a natural crystalline material known as langbeinite. It is an organic fertilizer with significant potassium, magnesium, and sulfur levels. Organic fertilizers are the best way to enrich the soil and promote healthy plants. These fertilizers are natural and release nutrients slowly, which means that plants can absorb them for a longer time.

Langbeinite, a favorite fertilizer of many, provides all three of K, Mg, and S in each particle. It helps provide ample nutrients to plants without being too concentrated in one area.

Because of its higher density, langbeinite is water-soluble but doesn’t dissolve as quickly as other common K fertilizers. You will have to grind it and mix it with water before you can spread it on your crops.

Benefits of Using Organic Fertilizers on Plants

Fertilizers are a crucial part of the gardening process. They provide plants with the nutrients that they need to grow and thrive. But what if we told you that there was a way to get these nutrients without using chemical fertilizers?

Organic fertilizers such as Sul-Po-Mag are a great alternative to chemical fertilizers. These fertilizers are popular for providing nutrients to plants and helping them grow. Let’s examine what makes them preferred over chemical fertilizers.

  • Since organic fertilizer doesn’t contain any harmful chemicals or additives, it is more environmentally friendly. It doesn’t produce any harmful runoff into the environment as it doesn’t contain any synthetic chemicals like artificial nitrogen or phosphates.
  • Organic fertilizer is safer for people and animals who come into contact with them.
  • Naturally occurring fertilizers are more sustainable and non-toxic than chemical fertilizers.
  • It is less expensive.
  • Organic fertilizers provide numerous benefits in different areas, from plant growth to soil improvement.
  • They’re the safest option, and most importantly, they promote healthy growth and massive production.
  • The low absorption rate of these fertilizers makes them less likely to overfeed your plants.
  • It can survive heavy rainstorms and irrigation sessions that could wash chemical fertilizers away.
  • It improves soil structure by helping it to retain nutrients and moisture
  • It doesn’t contaminate lands and waters

Three Essential Ingredients In Sul Po Mag

As a secondary fertilizer, the Sulfate of Potash Magnesia supplies potassium, magnesium, and sulfur plants need to grow. The three components of this fertilizer completely break down in the soil and reach your crops without negatively affecting soil quality. Keep reading if you’d like to know about the three essential ingredients in Sul-po-mag and their advantages.


  • Potassium is an extremely important element – it regulates many of the plant’s internal processes and makes up part of the fluid.
  • A strong supply of potassium is crucial to the well-being and development of plants.
  • It aids in the synthesis and formation of protein.
  • It improves how fruit and vegetables taste.
  • It helps plants grow quicker, be hardier in drought, and be weather tolerant.
  • Fight off disease and insect infestation


  • Magnesium is found in the central core of the chlorophyll molecule in plant tissue, so it’s key for proper plant growth.
  • It’s responsible for producing chlorophyll, the compound behind photosynthesis.
  • It also activates specific enzyme systems.


  • Sulfur is a key component in plant proteins, amino acids, and oils.
  • It has been shown to help activate enzymes necessary for bodily functions.
  • Also, it promotes the formation of chlorophyll.
Chemical FormulaK2Mg2(SO4)3
Fertilizer Analysis22% S, 10.8% Mg, and 21.5% K2O
Water Solubility (20 °C)240 g/L
How To Apply Sul Po Mag 2
Sul-Po-Mag 0-0-21.5 Sulfate of Potash Magnesia – via Reddit

5 Different Ways On How To Apply Sul Po Mag

When adding langbeinite to soil, follow instructions on the packaging to get the proportions right. A few general guidelines on how to use langbeinite are given below:

1.      For Plants In Containers

  • Add 1 tbsp of fertilizer per gallon of soil
  • Apply it monthly for established plants or as needed

2.      For Vegetable Gardens And Flower Beds

  • The recommended use of langbeinite is 1-2 pounds (0.5-1 kg.) per 100 square feet
  • Apply Once a month for established plants during the growing reason
  • Add 1 to 2 tablespoons of side dressing to each plant

3.      Premixing Soil

  • it is advised to use a pound of langbeinite for every two and a half centimeters of tree trunk diameter
  • You can mix it in the soil starting at the drip line and make sure you only do this once a year

4.      For Trees

  • In the case of new trees, mix 1/4 to 1/2 cup with the backfill soil taken from around the tree. Then refill the hole with this amended soil.
  • For established trees, mix 1 to 2 pounds of fertilizer per 1″ of trunk diameter into the soil surface. Evenly distribute it toward the drip line (the area under the outer circumference of the tree’s branches).

5.      For Row Crops

  • Apply 200 to 500 pounds per acre, based on an analysis of the soil and the crop’s needs.

Make sure to water thoroughly as langbeinite is water-soluble. As long as you mix it with the soil and water for about two weeks, it is able to take up the nutrients.

Benefits Of Sul Po Mag (Langbeinite)

  • Langbeinite has a neutral pH so that it won’t affect the alkalinity or acidity of your soil. While other sources, such as dolomite, increase your soil’s pH. Langbeinite is also different from elemental S and ammonium sulfate, which decreases your soil’s pH.
  • This neutral nature makes this natural fertilizer a very good source of Potash and Magnesium for areas with acidic soil.
  • Sul po mag is a long-lasting formula. Since it is a crystalline compound, it will dissolve gradually throughout the growing season.
  • It is one of few 100% natural rocks exclusive of sewage sludges, manure, or filers.
  • The low amount of mineral chloride in Sul-po-mag makes it an excellent fertilizer unlikely to burn plants. Therefore, it is good for the plants that need high Potash and Magnesium and is sensitive to Chloride.
  • Sul-Po-Mag can be used in areas with either too much calcium or too little magnesium or potassium.
  • Sul-Po-Mag is an excellent fertilizer for any vegetable or fruit crops needing extra fertilization.


When applied at typical agronomic rates, Sul po mag fertilizer has no restrictions for the environment or nutritional purposes. So now that you know how to apply Sul Po Mag, you can enrich your garden. Feel free to share your experiences with this fertilizer by leaving a comment!