What Is Cotton Burr Compost?

Cotton Burr

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Cotton burr compost is a product made from materials left over after the cotton fibers are harvested and processed. As compost, it's much like any other-it's made up of scraps, however it has other uses in the home landscape and is described as a soil amendment excellent for plants. It was first introduced in the late 1970's but has recently become more widely available and is drawing the attention of home gardeners. While some experts extol it's virtues citing high levels of nutrients present in the discarded burr, environmentalists and organic growers caution about the high load of synthetic pesticides and herbicides commonly applied to cotton crops.

In recent years, cotton has garnered attention and a certain degree of notoriety due to the high levels of synthetic pest management products as well as the amount of waste generated. As a result, cotton growers and industry organizations are focusing on ways to reduce synthetic substances and developing new uses and products from cotton crop waste. One of these is cotton burr compost. If you decide to try it in your own garden there are several important factors and questions to consider before making a purchase.

What Is a Cotton Burr?

The cotton “burr” is the bud leaf (sepal) of the cotton plant. Similar to teasel or thistle, the burr is the sharp, spiny growth that brackets the cotton pod.

What Materials Make Cotton Burr Compost

Cotton burr compost may be made up of leaves, seeds, stalks, lint and burrs. However, the cotton burr is the part of the plant that contains beneficial nutrients and works as an effective soil amendment.

Benefits of Cotton Burr Compost

Cotton burrs contain the three main macronutrients needed by plants; nitrogen phosphate and potassium. A high nitrogen ratio facilitates quick release and bypasses the slow process of nitrogren delivery required by wood mulch products which first must break down in the soil. The burr also has numerous micronutrients, which serve as a food source for beneficial organisms, and aerate the soil by breaking down dense clay. This organic compost helps to neutralize soil pH and has superior water retention compared to peat moss.

How to Use Cotton Burr Compost

When properly processed, cotton burr compost is used as a soil amendment or as a top or side dressing in gardens. It is also added to lawns, potted plants and to mulch trees, shrubs and flowerbeds. It can be purchased in either coarse grade or fine grade form.

  1. Soil amendment: Add a 3 to 5 inch layer on top of the soil before planting and dig, hoe or til it in.
  2. Top or side dressing: Add a 2 to 3 inch layer around plants and work it into the soil.
  3. Lawns: Add a 1/4 inch layer of fine grade mulch to the lawn and rake it through the grass.
  4. Potted plants: Add 1 inch of fine grade on top of the soil and work it in with your fingers.
  5. Mulch: Apply a 1-inch layer, water thoroughly then add a light layer of heavier material such as wood chips on top. Cotton burr mulch is light and can be easily displaced by wind and runoff.

A bit pricier than standard wood based mulches, cotton burr compost has an effective soil life of up to two full growing seasons, according to test results compiled by the website garden.org,

Consider the Source

There are many products made from cotton waste. Depending on how the cotton is harvested, this waste might include fibers, lint, leaves, stems, and burrs. However, when the cotton is harvested using a picking machine instead of a stripping machine, the cotton burr is left on the plant to be turned back into the soil.

Because cotton has been traditionally grown using heavy applications of pesticide and, in some cases defoliants, it must be composted at high heat levels in order to remove synthetic impurities and petrochemical byproducts.

Texas is the largest producer of cotton in the United States. Other states growing cotton crop include Georgia, Mississippi, Arkansas, Tennessee and North Carolina. Some, such as North Carolina, have put specific regulations into place in order for companies to sell cotton waste as compost.

For cotton manufacturers, investing in the facilities and equipment needed to produce certified cotton burr compost is an expensive proposition. With potential for additional applications, which may even include a feed source for livestock, this by-product of cotton may continue to grow as an attractive recycling opportunity for cotton growers and processors.

Article Sources
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  2. https://citizensforconservation.org/2016/06/15/is-cotton-burr-mulch-safe-for-gardens/

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  7. https://www.ers.usda.gov/topics/crops/cotton-wool/cotton-sector-at-a-glance