California: A mere puff of steam could be the key to larger, healthier and more reliable strawberry yields in California – without toxic chemical fumigants.
Researchers at the University of California, Santa Cruz (UCSC) have been developing boiling water vapor as an alternative to chemical fumigants used to sterilize soil, chemicals that are believed to harm the environment, wildlife and growers themselves.
The team recently enrolled four organic strawberry growers in a trial that used sophisticated machines to inject gouts of steam into growing beds before planting.
Longtime strawberry farmer Rod Koda was among the participants. He told the LA Times the results were bigger plants, healthier plants and more strawberries.
The steam kills soil bacteria, fungi and weeds that can harm, kill or delay strawberry plants. For years, strawberry farmers had no alternative to chemical fumigants other than to “roll the dice” on losing an entire harvest to soil-borne diseases like fusarium wilt.
Certified organic produce cannot be grown with such toxins, forcing organic growers to either gamble with bankruptcy or switch to hydroponics. Steam fumigation now offers a promising alternative.
In reality, steam has been used for decades in greenhouses as a pesticide. Injecting it directly into soil is a novel take on a classic technique.”We’re going back to the future, where we’re looking back at an older technology but we’re finding more ways to engineer more efficiently and use it,” said Jenny Broome, a UCSC researcher working on the project.
The stakes are high. Strawberries are one of California’s most valuable and largest crops, with some 35,000 acres dedicated to the delicate fruit.
Growing close to the ground, in shade, with soft fruit, strawberries are a tempting target for pests of all classes, making organic cultivation especially challenging. That challenge has driven agri-tech innovation, from hydroponics to a new 3D textile originally developed as insect-proof body armor lining for the U.S. military, which recently tripled strawberry yields in North Carolina field tests by draping over fields.
For California’s organic growers, the old-fashioned power of steam may now offer the cleanest path forward.
