How to Use Worm Castings in Your Organic Garden

Thank you to Mind & Soil founder, Jordan Mara, for writing today’s post!

Nothing says Spring like those first warm evenings and shoots of growth throughout the garden – a welcome sight to every gardener! And with the 2022 season quickly approaching, countless gardeners are moving to more natural and organic organic gardening practices and beginning to incorporate one of the best kept secrets into their garden plan: worm castings. 

Why use worm castings in my organic garden?

Over the past decade numerous studies have been completed showing that worm castings are not only an incredibly sustainable amendment for your garden, but that they can help produce incredible results: 

• Increased  Germination: Given that worm castings are 100% organic matter, they retain significantly more moisture than sterile potting mixes. Because seeds need a  moist environment to germinate, this makes it significantly easier for seeds to germinate (and you don’t need to be watering them every day!). 
• Healthier & Happier Plants: What makes worm castings unique is that all the organic matter (think compost) passed through the worm’s digestive tract. When it comes out the other end (yes, worm castings are worm poop!) it has been coated with beneficial bacteria and enzymes that happen to be one of Mother Nature’s miracles and have been proven to help plants suppress plant diseases, according to a study completed by Cornell Researchers. 
• +200% Increase in Yield: From home-gardener experiments to studies done by the University of California, it’s been proven time and time again how much worm castings increase yield – with studies ranging anywhere from 57% to +200%!

So if you’re wanting bigger, healthier, and higher yielding plants this season, be sure to incorporate some worm castings!

When do I use worm castings? 

The two best times to be using worm castings are when:

• Starting Seeds
• Transplanting Seedlings into the garden

This ensures that your precious worm castings are put to use directly where the seed will be germinating and where the roots will be developing – allowing the plant to make the absolute most of the black gold! 

Bonus tip: Add 1-2” of organic compost across the top of your garden bed at the beginning and end of each season to ensure you’re always building your soil by replenishing the nutrients and microbial life. 

How much worm castings should I use? 

For seed starting, our favourite recipe (after more than 3 years of experimenting!) is to use:

• 4 parts finely sifted compost
• 2 parts pure worm castings
• 2 parts medium (i.e. peat moss, coco coir, pitt moss)
• 1 part perlite 

Combine these four inputs and mix (just like making a cake!) to create an incredible seedling mix. This can be used for both starting seeds in and potting up into. Alternatively,  we ship our perfectly measured and pre-mixed Worm Casting Seedling Mix all across Canada. All you have to do is open the bag and fill your seed cells! 

For transplanting, follow these simple steps for incredible results:

1. Transplant hole: Dig a hole approximately 6” deep for transplanting your seedling into.
2. Sprinkle: Sprinkle 1x handful of worm castings into the bottom of this hole and massage it in lightly. (bonus tip: Add 1tbsp of an all purpose organic fertilizer for an extra nutrient boost!)
3. Transplant: Pop your seedling out from its seed cell, gently loosen the roots, and place it into the transplant hole. Backfill with the surrounding soil and gently compact.
4. Top Dressing: Lastly, sprinkle an additional 1x handful of worm castings around the stem where it enters the soil. Gently massage it into the top 1” of soil. (bonus: Once again add 1tbsp of an all purpose organic fertilizer and massage it in as well!)
5. Water: Water thoroughly and your plant will be thriving in no time! 

Can I use worm castings instead of fertilizer?

Worm castings are decomposed organic matter (the same as compost, except that they have passed through the digestive tract of the worms), and generally have a very moderate nutrient profile. Therefore, they actually perform best when supplemented with an organic fertilizer. The combination of these two ensures that your plants are receiving both the nutrients from the organic fertilizer, as well as the microbial life and beneficial bacteria from the worm castings.

You can’t go wrong with worm castings and by incorporating them into your 2022 Garden Plan you are setting yourself up for an incredible gardening season full of big, healthy, and strong plants! 

Jordan is a gardener out of Canada who believes in the mental health benefits of gardening and runs an amazing YouTube channel and garden-focused Instagram account. He also sells some of the best gardening products on the market via his brand, Mind & Soil. Definitely go check out his page and give him a follow!