As spring approaches, it’s time to begin making preparations for our spring garden. This includes taking an assessment of our soil health and amending it as needed.

You can test your soil’s health through your local Ag extension. If you’re local to Tennessee, you can view these soil testing instructions from the TN Ag extension.

Two organic fertilizers for your soil include manure and worm castings (or vermicomposting). In this post, we’re going to discuss the differences between these two compost options.


Manure from omnivores like cow, horse, sheep, goats, or even alpacas, is a potential tool you can use for improving your soil. It adds organic material to your soil and helps with moisture retention and drainage. 

However, it’s not as simple as mixing in some manure with your soil and calling it a day. 

Fresh manure has too high of a nitrogen content in it, and can do more harm than good if you add it directly into your soil. Generally, it takes about six months to compost manure effectively before you can mix it in with your soil.

Additionally, using manure as a soil amendment tool raises your risk of weeds, as weed seeds can still be present within the manure.

When choosing which manure to add to your soil, keep in mind that there will be a different range of nitrogen, phosphorus, and potassium present in each type of manure. 

According to Fine Gardening, “Unless you have a manure tested, there’s no way of knowing for sure what its nutrient content is. Many factors influence the varying nutrient content of manures, including the type and age of the animal, the food eaten by the animal, the manure’s moisture content, the amount of bedding mixed in, the way the manure has been handled or stored, and its age.”

However, studies have produced generalized numbers for the N-P-K content of various manure types. Fine Gardening offers a great list, as well as the steps for composting fresh manure. You can find that here.

Finally, unless you have your own animals like cows or horses present on your farm or homestead, 

In our experience, we like using cow manure versus horse manure because of the possibility of more weeds in horse manure. Cows have a different digestive system (4 chambers) than horses, so we’ve noticed that weed and grass seeds seem to be more prevalent in horse manure. Horse manure is also higher in nitrogen than cow manure and considered “hot” so it’s recommended that gardeners use a hot composting method to deactivate germination when using horse manure.

We have cows and goats at Stoney Creek Farm, so we use their manure compost in our raised beds, but not in the U-Pick Garden—the garden is too big of an area to amend.

Use what you have, if possible. If you don’t have livestock, you’ll need to purchase manure that has already been composted. Some home hardware stores carry compost manures.

As always, we recommend making friends with other area farmers who can help you out with things like this!

Worm Castings / Vermicomposting

For most of us, using worm castings as organic fertilizer for your soil is an easier and more cost effective option than manure.

Creating your own vermicompost takes a shorter amount of time than composting manure—you can have compost ready in as little as 3 months. Generally, it takes between 3 – 6 months to have vermicompost ready for your garden.

It’s also relatively inexpensive to create—you just need a few starter materials, some worms, and then you’re ready to begin! 

In the next post in this series, we’ll be providing instructions for how to create your own “worm farm.”

Vermicompost has also been shown to have high concentrations of nutrients like:

  • Magnesium
  • Calcium
  • Potassium
  • Phosphorus
  • Nitrogen

… All things your soil needs to produce healthy, fruitful plants this spring season!


As you begin prepping for the upcoming spring and summer planting seasons, have you taken care of these 9 early spring chores for your garden?