How to Determine if Horse Manure is Properly Composted

How to Tell If Horse Manure Is Composted

An Introduction to Composting

Composting is the process of decomposing organic materials into nutrient-rich soil amendments. It is an excellent way to recycle waste and contribute to a sustainable environment. Among the various compostable materials, horse manure can be a valuable resource for gardeners and farmers due to its high nitrogen content.

The Importance of Compost Quality

Using properly composted horse manure ensures that your plants receive essential nutrients while minimizing the risk of pathogens or weed seeds contaminating your garden. To determine if horse manure has been adequately composted, follow these simple steps:

Step 1: Visual Inspection

Absence of Foul Odor

When composting occurs efficiently, foul odors associated with fresh animal waste disappear during decomposition. Properly composted horse manure should have an earthy smell resembling rich soil rather than a pungent or ammonia-like odor.

Dark Brown Color

As microorganisms break down organic matter, they transform it into humus – a dark brown material often referred to as “black gold.” Well-composted horse manure should exhibit this characteristic dark brown color throughout the entire pile.

Step 2: Texture Test

Crumbling Consistency

Take a handful of the suspected compost and gently squeeze it in your palm. If it crumbles easily like dry soil, then it indicates proper decomposition. On the other hand, if the material remains sticky or clumpy, further aging may be needed before using it in your garden beds.

Step 3: Heating Activity Assessment

No Active Heat Generation

During initial stages of decomposition, microbial activity generates heat, causing the compost pile to warm up significantly. However, as decomposition progresses and the materials break down further, this heating activity subsides. By using a thermometer or simply feeling the temperature of the manure pile with your hand (with caution), you can assess whether it has cooled down sufficiently.

Step 4: Weed Seeds Evaluation

Absence of Sprouting Seeds

One common issue when using uncomposted manure is an abundance of weed seeds that can take root in your garden beds. Composting should effectively kill most weed seeds due to high temperatures reached during the process. When inspecting horse manure for compost readiness, look for a noticeable reduction in sprouting weeds compared to fresh manure.


By following these guidelines, you can determine whether horse manure has undergone proper composting before using it in your garden or farm. Remember that patience is key – allowing sufficient time for decomposition will result in safe and nutrient-rich compost that benefits both plants and soil health. By incorporating well-composted horse manure into your gardening practices, you contribute not only to sustainable waste management but also to cultivating thriving green spaces.