Wool Pellets For Gardening: Natural Fertilizer, Water Management, & Pest Control
Written for Crooked Fence Ranch (https://crookedfenceranch.com). To see sources for this information, click here.
When sheep are sheared, the wool from the belly or backend of the sheep is often discolored, thin, and considered “waste wool.” This unusable wool can account for as much as 20% of the wool sheared from a sheep. Additionally, when market prices are low, sheep farmers often pile wool in the corner of the barn or throw it out rather than lose money having the wool transported and processed into useable fiber.
Pelletizing wool has many benefits for sheep farmers, for agriculture, and for the environment.
By pelletizing wool, waste wool is kept out of the landfill, and sheep farmers no longer have to throw away a valuable product but can instead be paid for what is turning out to be a valuable product. Wool is also considered an organic material in the USDA National Organic Program, making it a renewable and biodegradable product.
A study on the large-scale use of wool pellets in farming is underway. In May 2021, the University of Vermont began studying wool pellets in depth, knowing there was potential to help farmers reduce their use of phosphorus (and reduce the resulting run-off) as well as sequester the carbon found in the wool by putting it back into the soil.
It’s not just farmers who can benefit from wool pellets, however. Gardeners will also see such benefits in soil nutrition, water management, and pest control.
Wool pellets contain small amounts of phosphorous and potassium but impressive quantities of nitrogen. Generally, garden compost provides about 1-2% nitrogen, poultry manure provides about 4.5% nitrogen, and sheep wool can provide between 9.3 - 14% nitrogen.
Wool pellets can improve plant growth. Greenhouses using wool pellets could grow organic tomatoes from seed to market in around 38 days, far less than the usual 76 days without wool pellets. Some studies have shown that tomatoes grown using wool pellets are 58 - 69% larger than those grown without fertilizer.
Pest control, including against weeds when the pellets are used as a barrier, is a surprising benefit of using the pellets. This is particularly so regarding slugs, as the barbed nature of wool is an irritant to slugs. Though not tested, anecdotal evidence has suggested that wool pellets might also help protect plants, such as strawberries, against aphids. Testing continues to determine exactly how wool pellets work against garden pests.
Wool pellets have been used in wilt studies, in which a plant is allowed to wilt and die without water being added. The results have been impressive, with plants in traditional soils wilting on day 1 and 2, and dead by day 5 and 6. Plants in soil with wool pellets, however, did not wilt until day 7 and 8, dying on day 14. This is because wool can hold 20 - 30 times its weight in water, releasing it slowly over time. While many potting soils and products claim to retain water, the key is in the slower release over a longer time, which is what wool pellets can do. The pellets allow water to be held closer to the root than other methods.
Wool pellets also make excellent mulch, helping with water retention and reducing weed growth. While straw mulch tends to break down quickly and allow weeds a chance to get a foothold, wool mulch breaks down more slowly. Wool pellets that are worked into the soil will begin breaking down in about three months, while pellets that are used as mulch will last nearly 12 months. Some studies have shown that wool can last as long as two years before it is fully decomposed, so multiple growing season benefits may be possible.
As the sixth largest state in sheep production, South Dakota wool producers are in a good position to provide a completely natural and renewable product to increase productivity for both farmers and gardeners.
When sheep are sheared, the wool from the belly or backend of the sheep is often discolored, thin, and considered “waste wool.” This unusable wool can account for as much as 20% of the wool sheared from a sheep. Additionally, when market prices are low, sheep farmers often pile wool in the corner of the barn or throw it out rather than lose money having the wool transported and processed into useable fiber.
Pelletizing wool has many benefits for sheep farmers, for agriculture, and for the environment.
By pelletizing wool, waste wool is kept out of the landfill, and sheep farmers no longer have to throw away a valuable product but can instead be paid for what is turning out to be a valuable product. Wool is also considered an organic material in the USDA National Organic Program, making it a renewable and biodegradable product.
A study on the large-scale use of wool pellets in farming is underway. In May 2021, the University of Vermont began studying wool pellets in depth, knowing there was potential to help farmers reduce their use of phosphorus (and reduce the resulting run-off) as well as sequester the carbon found in the wool by putting it back into the soil.
It’s not just farmers who can benefit from wool pellets, however. Gardeners will also see such benefits in soil nutrition, water management, and pest control.
Wool pellets contain small amounts of phosphorous and potassium but impressive quantities of nitrogen. Generally, garden compost provides about 1-2% nitrogen, poultry manure provides about 4.5% nitrogen, and sheep wool can provide between 9.3 - 14% nitrogen.
Wool pellets can improve plant growth. Greenhouses using wool pellets could grow organic tomatoes from seed to market in around 38 days, far less than the usual 76 days without wool pellets. Some studies have shown that tomatoes grown using wool pellets are 58 - 69% larger than those grown without fertilizer.
Pest control, including against weeds when the pellets are used as a barrier, is a surprising benefit of using the pellets. This is particularly so regarding slugs, as the barbed nature of wool is an irritant to slugs. Though not tested, anecdotal evidence has suggested that wool pellets might also help protect plants, such as strawberries, against aphids. Testing continues to determine exactly how wool pellets work against garden pests.
Wool pellets have been used in wilt studies, in which a plant is allowed to wilt and die without water being added. The results have been impressive, with plants in traditional soils wilting on day 1 and 2, and dead by day 5 and 6. Plants in soil with wool pellets, however, did not wilt until day 7 and 8, dying on day 14. This is because wool can hold 20 - 30 times its weight in water, releasing it slowly over time. While many potting soils and products claim to retain water, the key is in the slower release over a longer time, which is what wool pellets can do. The pellets allow water to be held closer to the root than other methods.
Wool pellets also make excellent mulch, helping with water retention and reducing weed growth. While straw mulch tends to break down quickly and allow weeds a chance to get a foothold, wool mulch breaks down more slowly. Wool pellets that are worked into the soil will begin breaking down in about three months, while pellets that are used as mulch will last nearly 12 months. Some studies have shown that wool can last as long as two years before it is fully decomposed, so multiple growing season benefits may be possible.
As the sixth largest state in sheep production, South Dakota wool producers are in a good position to provide a completely natural and renewable product to increase productivity for both farmers and gardeners.