The 411 on Compost Tea

Post courtesy of Guest Blogger Mike Lee, author of the Compost411.com blog.

 

A batch of bubbling compost tea.

 

Generations of gardeners have used compost teas to benefit plants and soil. Making your own compost tea can stretch the impact of your compost on your yard and garden, bringing different benefits to plants and soils.

Let’s start with the basics: what is compost tea and how does it work? Simply put, compost tea is water that has been exposed to compost. Compost teas in the past were made by letting compost soak in water. Gardeners then strained out compost debris from the water, using the liquid to water gardens or spray on plants. Today’s organic farmers, gardeners, and scientists studying plants and soils have discovered making compost tea with “active aeration” (in short, bubbling) helps release even more beneficial bacteria from compost into the liquid. Sending air bubbles into the compost tea brew increases the amount oxygen available in the water. This means the aerobic bacteria that seem to most benefit plants and soils can thrive while the compost tea is brewing.

 

That brings us to how compost tea works to benefit your plants and soils: “Steeping” compost in water releases microbes and water soluble nutrients into the liquid. These can benefit soil fertility (with vitamins and nutrients) and plant health (some compost teas sprayed on plants seem to help control diseases and create healthier plants). There are many possible benefits from the mix of nutrients and microbes in compost teas; in fact, farm and garden researchers continue cutting-edge scientific studies to figure out exactly why many plants seem to so greatly enjoy their compost teas.

This type of sack is perfect for brewing homemade compost tea.

 

Home gardeners have long brewed compost teas by letting compost steep in water, usually with the compost kept in some sort of “teabag.” Some gardeners continue this method, using materials as simple as a mesh bag to hold the compost and a five-gallon bucket to hold the brew. Small, bucket-sized aerators are available for home gardeners wanting to add more air while the compost tea is brewing; this is the most recommended brewing method by today’s garden researchers and organic farming experts. Certified organic farmers follow certain restrictions for applying compost and compost teas to edible fruits and vegetables; if you would like to use compost tea in the home garden, check with your local garden center or university extension office for compost tea application recommendations.

The gardener wanting to make her own compost tea for the first time can locate many compost tea kits with instructions for proper brewing. These kits usually include the essentials for making a good compost tea: compost tea bags, buckets, and aerators. If you decide to brew your own compost tea, remember that compost is still one of the most important ingredients; be sure to use your best, high-quality compost. Compost made from vermicomposting (worm bins) is often recommended for brewing up your own compost tea.

A lot of resources checked for this one, including:

http://www.ext.colostate.edu/sam/nl/16-spring.pdf
http://www.extension.umn.edu/garden/yard-garden/soils/vermicompost-tea/
http://extension.oregonstate.edu/douglas/sites/default/files/documents/hort/WhyUseCompostTea.pdf
http://extension.oregonstate.edu/lane/horticulture/documents/25gallonRubbermaidbrewerplans_2_.pdf