By Doug Halphin
One of the earliest childhood memories I have is helping my grandfather plant his vegetable garden each spring. He never used a tiller. Instead he carefully turned the garden soil with a fork. “Oh look” he would say “There’s a worm! Let him alone cause you always need as many worms in your garden as you can get”. I never knew why. Grandpa never said. But, at the age of 5, I took him at his word because he was the smartest man I knew. I often speak with people today who were told the same thing at the knee of a veteran gardener. They know they should have lots of worms in their garden but don’t understand why anymore than I did in my youth the reason. They just know it a good thing.
Today I understand why Gramps wanted worms in his garden. Worms are wonderful creatures that have been working the soil since the beginning of time. They are nature’s way of returning organic materials back to the soil depleted over the course of time and chemical usage. A worm’s job is to eat decaying and composting materials in the soil. Worms don’t eat soil. Instead they create a soil-like substance called worm castings. What happens in the digestive tract of worms is still a question that scientists at both Cornell and University of Ohio are currently studying. The benefits of the worm castings to the biological composition of the soil have been the focus of their studies for the last 10 years.
Simply adding worms to lifeless soil won’t solve your problems. Given a choice, most living creatures will not stay in an unhealthy environment. Each time a chemical is added to the soil in an effort to increase growth, kill a pest or treat a disease, beneficial microorganisms are destroyed. If gardeners add worms to soil that is not healthy, the worms will die or leave for better living conditions.
So, how do you encourage natural populations of worms into your garden? By adding organic amendments like worm castings and compost to the garden. A combination of the two will create a healthy environment in which the worms want to populate. Both are sold in garden centers and nurseries. A little goes a long way when it comes to worm castings. Research has concluded that by adding as little as 10% by volume seed germination increased over 50%. By adding as little as 20% by volume to potting or garden soil plant size increased by 48 to 50 percent, production of fruit by up to 50% and size and weight of produce by up to 19%. Similar results were derived from studies done on bedding plants as well. In addition they found that diseases were significantly depressed.
Worm castings are more than just organic fertilizer. They have high concentrations of two components that are essential for healthy and robust plants: humic acid and mycorrhizae. Humic acid helps the root system grow larger, increases the efficiency of the soil, transforms insoluble nutrients into usable ones, retards pathogenic fungi build-up, and stimulates microbial activity. Mycorrhizae is a symbiotic soil fungi that attaches itself to the root system of plants to help root systems better adsorb nutrients and increase water intake into plants. It will improve root growth and yield, increase the viability of transplants and lessen stress brought on by drought conditions.
Compost also provides many benefits to the garden, including improving soil structure, adding essential plant nutrients in a safe, slow-release form, and increasing water-holding capacity and drainage. It also attracts beneficial organisms like bacteria, fungi, insects – and worms! Both compost and worm castings are also helpful in suppressing diseases and harmful pests in the garden.
So, if you want a healthier garden and happier plants, tickle their roots by adding some worm-attracting compost and worm castings to the soil.
Doug Halphin is a Master Gardener and co-owner of Windswept Worm Farm located in an underground cave facility in Kansas City, MO. The business includes both the marketing of worm castings as an organic fertilizer and a bait route for recreational purposes encompassing 6 states.