Mar 13, 2023

Worm Force: Vermiculture helps soil, protects crops

Earthworms can rejuvenate soil to create healthy crops.

Through earthworms, unhealthy soil can quickly be made healthy, said George Hahn, owner and president of the Worm Gold/California Vermiculture LLC. 

“Go to a redwood forest or any forest,” Hahn said. “There are no bags of fertilizer behind those trees. How did they get enough nutrition to grow to the size they are?”

The answer, according to Hahn, is earthworms.

Earthworms provide the diversity of more than 30,000 different biological species, including bacteria, fungi, protozoa and beneficial nematodes, and promote the development of “soil food webs.” Healthy soil is teeming with tiny organisms that decompose organic material and enrich the soil, creating soil food webs. At the Jan. 16-17 Soilcraft Regenerative Agriculture conference in Pasco, Washington, Hahn discussed how soil is a living organism and said growers must understand soil biology. The conference was in-person and virtual. The Cardiff, California-based supplier said his organic soil solutions can help reduce soil salts and improve soil structure.

One ton an acre of earthworm castings applied to rootzones and spread throughout fields could provide 10% to 20% increase in yield, an optimal rate. Alternatively, brewing a mix kit of WormGold Plus, an organic non-toxic mixture consisting of pure worm castings (92%), fossilized kelp (for calcium) and rock mineral (for mineral balance), and other components for 16 to 24 hours would produce 4 billion earthworms following a biological multiplication of the earthworm produced biology.

The product includes chitin degraders and cellulose degraders, organisms which excrete chitinase and cellulase and then consume chitin and cellulose fungi. The product can be sprayed and added to irrigation and fertigation systems. 

“Think of the Pac Man game, which most of us played at one time or another,” Hahn said. “If a Pac Man string is a cellulose-based fungus, a pythium or a phytophthora, the cellulose-eating bacteria will excrete an enzyme called cellulase, which licks the line and then eats it. When excreted, it’s now a food source for the plant. What’s potentially a pathogen for the plant becomes food. The Pac Man eats it and feeds it to the plant.”

By delivering the beneficial excrement through castings, earthworms, produced from fertilized eggs, replenish soil nutrition. The process can lower soil salts, eliminate soil compaction and improve soil penetration as well as increase the soil’s carbon sequestration. Vermiculture also provides insect repellency and disease prevention, allowing trees and plants to mature faster plus extends crop shelf life.

“We found that over the past 15 years, every single insect pest when we apply this won’t touch the plant,” Hahn said.

Growers growing in high salt sand land experience small water retention, with plants using only an inch of 10-acre inches of water applications during the season. The product increases moisture retention from 10% to 20%, reducing irrigation needs by up to 50%, Hahn said. Using vermiculture, the same 10-acre inches could consume 3-acre inches, allowing growers to watch their soil retain moisture and irrigate only when necessary. The earthworms could potentially cut water consumption by two-thirds, Hahn said. 

“The increase in recyclers will dramatically increase the plants’ root mass,” Hahn said. “We are sure this will help on that water retention because the roots are now being fed by biology, not just chemical salts.”

An apple grower using the solution reduced bitter pit incidences to below 3% while a blueberry grower experienced higher plant vitality and a 21% yield increase as well as few pests and diseases, Hahn said. In a lettuce and crickets experiment, the insects didn’t attack the treated lettuce versus the untreated sample. A New Mexico chili pepper grower experienced higher yield and compared to the ineffectiveness of numerous herbicides, saw the suppression of the verticillium dahliae, botrytis and epiphyllum diseases and destructive pepper pathogens.

In nuts, as part of a USDA study, a California pecan grower witnessed a 400% increase in yield as well as eliminating pecan weevil and pecan scab threats, Hahn said. The added nutrition helped eliminate fruit drop by the end of the four-year study, he said.