What Are Worm Castings?
Worm castings contain a highly active biological mixture of bacteria, enzymes, remnants of plant matter and animal manure. The castings are rich in water-soluble plant nutrients, and contain more than 50% more humus than what is normally found in topsoil.
Worm castings are packed with minerals that are essential for plant growth, such as concentrated nitrates, phosphorus, magnesium, potassium and calcium. It also contains manganese, copper, zinc, cobalt, borax, iron, carbon and nitrogen. However, the best of all is that these minerals are immediately available to the plant, without the risk of ever burning the plant. Remember that animal manure and chemical fertilizers have to be broken down in the soil before the plant can absorb them.
As the organic matter moves through the alimentary canal of the earthworm, a thin layer of oil is deposited on the castings. This layer erodes over a period of 2 months. Although the plant nutrients are immediately available, they are slowly released to last longer. The bacteria in the alimentary canal of the earthworm transform organic waste to a natural fertilizer. The chemical changes that the organic waste undergoes include deodorizing and neutralizing. This means that the pH of the castings is 7 (neutral) and the castings are odorless (they smell like a forest after rain). The worm castings also contain bacteria, so the process is continued in the soil, and microbiological activity is promoted.
What Can Worm Castings Be Used For?
Worm castings can be used as an ingredient of potting soil (as plant nutrients) for plants in and around the house. It can be used as a planting additive for trees, vegetables, shrubs and flowers. When used as a mulching material, worm castings will ensure that the minerals are absorbed directly into the soil when it is watered. Because worm castings will never burn plants, you can use as much of it as you like.
Benefits of Worm Castings
The humus in the worm castings extracts toxins and harmful fungi and bacteria from the soil. Worm castings therefore have the ability to fight off plant diseases. The worm castings also have the ability to fix heavy metals in organic waste. This prevents plants from absorbing more of these chemical compounds than they need. These compounds can then be released later when the plants need them.
Worm castings act as a barrier to help plants grow in soil where the pH levels are too high or too low. They prevent extreme pH levels from making it impossible for plants to absorb nutrients from the soil.
The humic acid in worm castings stimulates plant growth, even in very low concentrations. The humic acid is in an ionically distributed state in which it can easily be absorbed by the plant, over and above the normal mineral nutrients. Humic acid also stimulates the development of micro flora populations in the soil.
Worm castings increase the ability of the soil to retain water. The worm casts form aggregates, which are mineral clusters that combine in such a way that they can withstand water erosion and compactions and also increase water retention. Worm castings reduce the acid-forming carbon in the soil, and increase the nitrogen levels in a state that the plant can easily use. Organic plant wastes usually have a carbon-nitrogen ratio of more than 20 to 1. Because of this ratio, the nitrogen is unavailable to plants, and the soil around the organic waste becomes acidic.
How to use Worm Castings:
For Germination –Use 20 to 30% worm castings with sand as an excellent germination mixture. It will also ensure continuous and lush growth for about three months, without you having to add any other plant food.
As a Soil Conditioner—if you have a layer of barren soil, add a layer of worm castings and give it some water, you will be surprised at the growth of your first season’s plants.
As a Fertilizer—Sprinkle worm castings around the base of plants or lightly dig it in, and then add water. They can also be sprinkled on a larger scale with a spreader. Remember: you cannot use too much worm castings; they cannot damage your plants.
As a Liquid Fertilizer—Worm castings can easily be mixed with water. Use 1 cup worm casting for every gallon of water and wait 1 week. This liquid can be used as an excellent fertilizer or leaf foliate spray. It also helps to control insects. Many people prefer this method of application.
Worm Castings – What Are They? How Do They Work?” Tasteful Garden. N.p., n.d. Web. 20 Sept. 2013. <http://www.tastefulgarden.com/store/pc/worm-casting-d114.htm