using worm castings in potting mix

The Biggest Secret To Vegetable & Flower Power – Using Worm Castings!

Yes, using worm castings really is one of the biggest and best secrets of all time when it comes to growing amazingly healthy and productive plants. Period!

Worm castings are quite simply the most powerful, incredible, plant-energizing fertilizer & soil conditioner around. Yes, even more than compost – which, of course, is pretty special in its own right.

Worm castings are easy to use everywhere, and on any type of plant. That includes in the vegetable garden and in flowerbeds. And on hanging baskets, potted plants and containers, and shrubs and trees.

Best of all, castings are 100 percent safe, natural and completely organic.

Here is a look at just exactly what they are, and how using worm castings can be a great way to growing healthier, more productive plants.

What Are Worm Castings – And How Do They Work?

Worm castings are the dried manure of worms. Unlike the manure of chickens, horses, cows or rabbits, castings are ready to use immediately.

As worms move through soil, they chew and digest tiny organisms and bits of organic material. Those materials are then ground down in their digestive system. It exits as a perfect blend of organic nutrients.

Worm castings contain all kinds of powerful organic material and minerals. Minerals such as calcium, nitrogen, phosphorous, potassium and magnesium. All of which, coincidentally, are critical nutrients needed for plants to grow strong and healthy.

How To Use Worm Castings

As you will see below in detail, we use worm castings in a variety of ways and methods. We mix dry castings in our seed starting soil and potting soil. And we mix them into planting holes for vegetable plants, flowers, shrubs, bushes and trees too.

But it doesn’t end there. By soaking the castings in water, it creates an incredible liquid fertilizer. One that helps grow bigger and more productive containers plants and hanging baskets. (See : How To Make Your Own Natural Liquid Fertilizer)

Although you can raise and harvest worm castings with a homemade “worm-farm” set up, they can also be readily purchased. The key when purchasing is to make sure you are getting 100% castings.

There are many knock-off products that contain mostly fillers, with just a fraction of worm castings. But it is the all-natural, 100 percent pure castings that work like no other. Product Links : 100% Worm Castings 30lb. Bag – 100% Castings 15lb. Bag

Here is an in-depth look at how to use worm castings all throughout the landscape:

Using Worm Castings – The Where & How

For Seedlings – We mix worm castings into our seed starting soil at a rate 1 cup of castings for every 1 cup of potting soil.

The slow release of nutrients is perfect for young seedlings to get off to a strong, healthy start. See : How To Create The Perfect Potting Soil

For Vegetable & Flower Transplants – When transplanting vegetable plants and flowers into the soil, we use a quarter cup of castings mixed into every planting hole.

We also sprinkle a few tablespoons mixed into the soil around the surface of the plant. This acts as a slow release fertilizer every time it rains, or you water.

Baskets & Containers

Hanging Baskets – If you are creating your own hanging baskets, mix in 1/2 of cup of castings in the potting soil at planting time.

If purchasing pre-planted baskets, sprinkle in a quarter cup of castings on top of the soil. As you water, or as it rains, the nutrients leach down into the plant’s roots to provide big power.

Re-apply ever month to keep baskets looking great all season long.

Container Plantings – Much like hanging baskets, mix in a 1/2 cup of castings to the soil in your containers. Once a month, add a quarter cup of castings to the top of the soil.

Liquid Compost Tea – As mentioned earlier in the article, you can create an incredible all-natural homemade “miracle growing liquid fertilizer” with castings.

To create, mix 1/2 to 3/4 cups of castings with 2 gallons of water. Let the solution soak for 24 hours.

You can then use the solution to fertilize vegetable plants, flowerbeds, hanging baskets, containers and more. For vegetable plants, we apply 1/4 gallon to each root zone when fertilizing.

For containers and hanging baskets, we water with the solution every few weeks. You will be shocked at the power it provides to your plants.

Perennials – When planting, transplanting, or splitting and dividing perennials, mix in a quarter cup of castings to each new planting hole.

Shrubs and Trees – Castings are excellent for planting shrubs and trees too! For traditional 1 gallon containers, mix in 1 cup of castings when planting.

Here is to using worm castings to power your plants to new heights this year!

Worm castings are quite simply the most powerful, incredible, plant energizing all-purpose organic fertilizer you will ever use. See why, and how to use!

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Assessing the Ratio of Worm Castings to Peat-based Potting Mix for Greenhouse-grown Organic Basil

Guest Authors: Anisah Madden, Summer Research Intern and Mehdi Sharifi, Assistant Professor/Canada Research Chair in Sustainable Agriculture, Trent University

There is evidence that the use of worm castings as an amendment have the potential to supply sufficient nutrients to leafy vegetables during their growth period. A greenhouse experiment was recently conducted at Sustainable Agriculture Program in Trent University to access the optimum ratio of worm castings to growing media for organic basil (Ocimum basilicum).

Worm casting treatments were combined with an organic peat-based potting mix1 in different percentages (0, 15 and 30% weight basis) to study the effects on basil plant growth and nutrient availability. The total concentrations of carbon, nitrogen and sulphur in the worm casting were 13%, 1.05 % and 0.24% respectively on a dry weight basis. The moisture content of the worm casting amendment was between 20 to 22%.

Worm castings, (also called vermicompost), are the end product of the breakdown (digestion) of organic matter by earthworms. Vermicompost is rich in nutrients, beneficial bacteria and enzymes, and has been shown to improve soil structure, aeration, porosity, drainage, and moisture holding capacity, while exhibiting a positive effect on plant growth and health.2

The results of this project indicated that a mixture of 15% worm castings to 85% peat-based potting mix provided sufficient nutrients for basil plants during their growing cycle (8 weeks), significantly enhancing the majority of basil traits including plant height, biomass, leaf area, and number of branches compared with other treatments – without any need for supplemental nutrient application (Table 1).

Worm castings applied to the potting mix at the higher rate of 30% did not further enhance the growth traits observed, and only showed a marginal increase in nitrogen and sulphur uptake by the plants compared with the 15% treatment rate.

In addition, the study looked at the effects of adding biochar 3 and mycorrhiza 4 to the three different worm casting/potting soil treatments.

Biochar is the name for charcoal used as a soil amendment, and is produced by the pyrolysis (thermophilic decomposition of organic matter under high temperatures, in the absence of oxygen) of biomass (crop residues, or wood). Biochar is being researched for its carbon sequestration potential as well as its ability to improve soil fertility and agricultural productivity.

A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant. This beneficial relationship improves the plant’s ability to uptake water and nutrients, and additionally protects the plant roots from infection by pathogenic organisms.

In this study, mycorrhizal inoculation showed a positive significant effect on some basil plant growth parameters (shoot dry weight, leaf/stem ratio), and mycorrhizal dependency, and also improved nitrogen and sulphur uptake by plants; however, the addition of biochar did not show a significant effect on measured parameters.

This research project will help organic greenhouse producers to use the optimal amount of worm castings as an amendment for their growing media mix. The results of this project are also relevant to growers using integrated production methods as well as conventional growers who wish to minimise their synthetic fertilizer use, thereby reducing the risk of environmental damage while improving the sustainability of their production systems.

Ontario Ministry of Agriculture and Food