The Good, the Bad, the Microbial

SoilSoup creator receives AHS award for creative use of technology.

Some years, late tomato blight would kill everyone’s tomatoes on Bainbridge.

Then Jerry Erickson encountered “compost tea” – a home-brewed garden remedy that, when sprayed on the plants, would eliminate late blight.

“Why is this natural material so effective at doing what no chemical can?” Erickson asked himself.

One thing led to another, and this year Erickson’s SoilSoup in Seattle received the American Horticulture Society’s G.B. Gunlogson Award for “creative use of new technology to make home gardening more productive and enjoyable.”

Erickson had not even heard of compost tea until 1998, when a compost tea maker gave a demonstration at Winslow Green. The idea that this brown, tea-like liquid containing millions of microbes could eliminate diseases and be good for the soil intrigued him.

There was one drawback: the brewing device Erickson saw demonstrated was expensive and large. So, when two friends said they were thinking of getting one, Erickson offered to build one of his own.

A consultant for machine design by trade, Erickson worked on a gadget to aerate a mass of water in his machine shop at home.

The aerator, which he eventually patented, mixed air into every part of the compost tea, encouraging the growth of the beneficial microbes that need oxygen over the anaerobic microbes that are bad for plant life.

Erickson also studied up on microbiology starting with his wife’s nursing book, and then an English translation of N.A. Krasil’nikov’s “Soil Microorganisms and Higher Plants” he found on the internet.

Working with local farmers such as Art Biggert, he tested and refined his brewer.

“Jerry would say, ‘I think I have something that might work,’ and then the ‘bioslime’ would clog the pipes and burn out the motors and he’d redesign it,” Biggert said.

Over the course of two years, Erickson came up with an aerator design and mix of nutrients that could brew a tea full of beneficial microbes from a worm compost tea bag.

Erickson and his business partner Eric Neff marketed SoilSoup’s first compost tea kits, including the aerator – dubbed the Bio-Blender – and its nutrient mix, to small organic farmers and home gardeners.

While they still sell the kits to consumers, their most successful products have been large-scale “SoilSoup Kitchens” to garden supply stores, which cook up and sell small quantities of the compost tea to individual gardeners.

Dawn Levy of Bainbridge Gardens says they sell up to 200 gallons a day, and sold well over 5,000 gallons last year. That’s despite the fact that compost tea is less convenient to apply than chemical fertilizers – because the brew contains living microbes, it has to be used the same day it is brewed.

“It takes some convincing for some people,” she said. “But I haven’t heard any complaints yet. Compost tea is the least toxic thing you can do.

“Usually, it’s the home gardeners who misuse chemicals. The first reaction to a problem is to spray.”

As concern over the health effects of chemical pesticides has grown, so has the popularity of compost tea. Many chemical treatments, says Biggert, will kill beneficial microbes, while pathogens hide in a dormant protein shell, only to emerge later. The aerobic microbes in compost tea, by contrast, will eat through that shell.

“Pathogens are poor competitors but good at reproduction,” he said. “In a biodiverse soil, the pathogens would be eaten by the others.”

Levy says that she switched from chemical to organic gardening three years ago, and although the first year was tough, she isn’t seeing aphids in her garden this year.

“From the position of doing the right thing, it’s rewarding,” Erickson said. “I’ve never been in a business that (had) a feeling of contribution, and this definitely does.”

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