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How To Use Worm Castings To Fertilize Tomato Plants – Grow Your Best Tomatoes Ever!

When it comes to powering your tomato plants to amazing growth and an incredible harvest, you simply can’t get better than fertilizing your plants with worm castings!

Worm castings are a 100% fully organic natural fertilizer that has the perfect balance of nutrients to help power tomato plants. Not only that, they also improve the structure of the soil that tomatoes grow in – all while helping to retain moisture for the roots of plants as well. 

One of the best parts of using worm castings is that you can use them all throughout the stages of a tomato plant’s life. From helping to power young seedlings and transplants, to using castings as a liquid fertilizer on mature plants, they truly are a must for helping to grow strong and healthy tomato plants.

fertilize tomato plants with worm castings
They might be small – but worm castings are packed full of nutrients. The little pellets above are perfect for powering your tomato plants!

What Are Worm Castings?

Worm castings are quite simply the dried manure of worms. As worms travel through the soil, they are constantly consuming the soil and all sorts of organic materials. Their food sources can range from bits and pieces of decaying roots to old leaves, stems and more.

These materials mix with the soil and break down as they travel through a worm’s digestive tract. The end result is worm castings. And are they ever powerful! Castings are loaded with nutrients such as calcium, nitrogen, magnesium, phosphorus, and potassium – all of which tomato plants need to thrive and grow strong. 

When used with growing plants, the castings release all of their beneficial nutrients as they break down and leach into the soil. Even better, they do so in a way that tomato plants can absorb all of the power easily and quickly into their root systems.

A chicken standing in the grass.
While manure created by animals like chickens is amazing for powering plants, it has to age before it can be used around tomato plants. That isn’t the case for worm castings, which can be used right away.

Worm castings are similar to the manure created by chickens, horses and other farm animals. Both are perfect for powering tomato plants and improving the soil’s structure. However, they are also quite different in one important way.

Animal manure is very “hot” and ultra powerful when fresh. These manures need time to age and become safe to use around tomato plants without the worry of burning the plants. But you can use worm castings right away!

Although they are full of energy, castings will not burn plants. Instead, they gently but consistently release their nutrients to power the plants at a slow and steady pace – without any worry of burning or harming the plants as they grow.

How To Use Worm Castings With Tomato Plants

You can create your own homemade worm castings by a process called vermicomposting. The fancy name is nothing more than the process of farming worms in bins and allowing them to break down organic matter and food waste. In the end, the worms then provide homemade castings to use for your tomato plants. 

However, for most gardeners, it’s far more simple to purchase commercial castings. Castings have become quite popular in recent years and are readily available. Even better, they are also quite affordable – although you do want to make sure when purchasing to buy 100% pure worm castings to get the most bang for your buck. (Affiliate Product Link: Worm Bliss – Pure Organic Earthworm Castings

fertilize tomato plants with worm castings
You can add castings to your seed starting soil to get the seedlings off to a powerful start.

When, Where & How To Use Castings On Tomato Plants

There are a whole slew of ways to use worm castings to power your tomato plants – and it all starts with using castings when starting your own plants from seed indoors.

Using Worm Castings When Starting Seeds 

You can use worm castings right from the beginning of a tomato’s life. They will provide your seeds with an initial boost of nutrients and power to help them both germinate and grow strong and healthy. 

Whether you are using commercial seed starting soil or creating your own mixture, you can include worm castings. And, there’s no worry about burning delicate seeds and the new emerging tomato seedlings with them! 

Simply mix in 1/4 cup of castings for every 1 cup of seed starting soil or potting soil. The castings will help to lighten the soil, all while adding vital nutrients at the same time. See our article: “The Best Way To Start Tomato Seeds Indoors”

Tomato Transplants

When it’s time to get your tomato transplants in the ground, you can once again use worm castings. This will help set up your transplants for success since castings are the perfect slow-release fertilizer. When planting transplants, mix a quarter cup of worm castings into each planting hole

Fertilize tomato plants with worm castings
Before placing your tomato transplant into the soil, add a quarter cup into each planting hole to help power the plant’s roots right from the start.

The castings will get your transplants off to an amazing start. Why? Because they provide plants with exactly what they need right at their root level. You can also use the castings if you are planting your tomatoes in containers. For each container, mix one-half to one full cup of castings into the soil prior to planting the tomato.

Top Dressing Tomato Plants – How To Use Worm Castings To Fertilize Tomato Plants

As tomato plants grow and mature, you can also use worm castings as a powerful top dressing. To do this, simply sprinkle castings on the surface of the soil surrounding the root zone of each tomato plant. For this, a quarter cup of castings around each plant will do the trick.

Every time you water or it rains, the castings act as a slow-release fertilizer. It’s actually best to do this monthly to keep a steady supply of nutrients going down to your plants. Again, there is no worry about the castings touching and burning the foliage or stems of the plant. 

Creating A Powerful Tea – How To Use Worm Castings To Fertilize Tomato Plants

Last but not least, you can use castings to help power your tomato plants by creating a high energy worm casting tea. You can use this liquid on the soil around the plants as well as directly applying it to the foliage. And it can really help tomato plants thrive!

watering vegetable plants
Worm casting tea acts like an all-natural, power-packed liquid fertilizer.

To make worm casting tea, add one-half to one cup of castings to a gallon of water. Allow the mixture to soak for 24 to 48 hours. Stir or shake up the mixture a few times each day during the time frame to allow the castings to leach more easily into the water.

Strain the liquid from the remaining castings. Next, apply the liquid tea to each plant’s root zone at a rate of about 1/4 gallon per plant. The powerful liquid will give your tomato plants the perfect dose of all-natural fertilizer! And in return, your tomato plants will thank you with serious growth and production!

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