Growing Vegetables with Worm Castings - Lincoln County Master Gardener™ Association

Worm Poo, do your plants love it?

With my Master Gardener™ Apprentice Project I hoped to show whether or not feeding plants using worm castings (also called vermicompost) and worm casting tea resulted in healthier, more productive plants.

I started with two beds, each receiving the same amount of sunlight and having the same growing conditions, as well as starting with the same soil type and nutrient density in each bed. I planted the same plants in the same location in each bed: 1 Tomato, 1 Zucchini, 5 Green Beans, 1 Pepper, 2 Cilantro.

I already had an “under the counter worm bin” that was home to red wigglers as well as an old cooler that I used as another worm bin, so I had access to plenty of worm castings to use. I feed them garden scraps as needed and topped them with dried plant material and a layer of cardboard.

When I planted the Worm Bed I included a handful of worm castings into each planting hole, I also scuffed worm castings into the top of the soil around each plant; the control bed was planted directly into the existing soil with no added fertilizers.

I added more worm casting to the worm bed 3 times during the growing season, about once a month I would scuff a handful of worm castings into the soil around each plant. I also watered it with worm casting tea at least once a month. Both beds received the same amount of water throughout the season.

The final produce count for each bed:

Worm bed: 44 Green Beans, 6 Zucchini, 1 bunch of Cilantro, 3 Tomatoes, 1 Pepper,
Control Bed: 31 Green Beans, 3 Zucchini, 1 Tomato,

The worm bed produced more on each plant, the plants grew
faster as well, though this slowed down around the middle to the end of season.

I never noticed any pests on any of the plants so I can’t say if the worm bed was more pest resistant or not but in the last few weeks the tomato in the worm bed has begun to look sickly; yellowing and dying leaves, and now mold has started to grow on it’s main stem. This could be due to over-watering but with so many people in and out of the garden it’s hard to tell.

Red Wiggler—Eisenia andrei

Overall, I think that the worm bed produced healthier, faster growing plants; they produced more and started producing sooner than the control bed. Worms are easy to feed and care for and make a safe and easy to use nutrient boost for your plants! They don’t require much attention other than occasional feedings, and they like to eat most garden and kitchen scraps.

To set up your own worm bin:

Find a container, two nested plastic bins work well, the top will have drainage holes and will house the worms and their bedding and the bottom will collect the leachate (a dark liquid that is rich in beneficial microbes and nutrients – mix with water and feed to your plants)

Fill the top bin with 4 to 6 inches of damp bedding, shredded paper or newspaper (nothing glossy), cardboard, coconut coir, leaves, or dried grass or plant material. Soak or dampen the bedding before adding to the bin.

Worms don’t have teeth so they need grit to help grind the food, add a handful of garden soil or ground egg shells to the bin (I like to mix a shovelful of native soil with the bedding).

Add your worms! Place them on top of the bedding and they will burrow down to escape the light.

Red wigglers are most active in a temperature range of 55-77°, they will eat less if temperatures are hotter or cooler than this. Place in a garage or somewhere protected during extreme cold or heat.

Maintain moisture level, if too wet add more bedding, if too dry add water but don’t water too often to avoid anaerobic conditions.

Feed your worms fruit and vegetable scraps, coffee grounds and filters, tea bags, and crushed eggshells. For faster decomposition you can chop scraps into smaller pieces if you want.

Do not add meat, dairy products, oily foods, pet waste, acidic items such as citrus, or onion or garlic (onion and garlic skin is fine to add).

For a new bin feed slowly at first, adding food about once a week and only adding what the worms can eat within that week.

Bury the food in a new location in the bin each week (if possible), bury under the top layer of bedding, covering food to help prevent fruit flies and odors.

Your vermicompost will be ready to harvest in three to six months, it will look like rich, dark soil.You can add another bin directly on top of current bedding material (will require drainage holes big enough for the worms to pass through). Add bedding and start feeding in the new bin. After a few weeks the worms will have left the old bin and will be feeding in the new bin.

Dump the bin onto a tarp under a bright light, the worms will burrow down to escape the light. You can scrape off the top layer of castings and repeat as the worms burrow deeper.

Images Courtesy of Oregon State University Extension Service.
You can find out more about worm casting composting here:
https://extension.oregonstate.edu/catalog/em-9034-composting-worms

Lincoln County Master Gardener™ Association

Worm Poo, do your plants love it?

To set up your own worm bin:

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Lincoln County Master Gardener™ Association

Worm Poo, do your plants love it?

To set up your own worm bin:

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