Composted horse manure is not a good fertilizer for established lawns. This is because the nitrogen in manure mostly comes from uric acid, which evaporates when exposed to air. If horse manure is spread on the top of a lawn, this uric acid will dissipate before it enters the soil, meaning your grass won’t receive much of that precious nitrogen.
- The nitrogen in horse manure compost evaporates if used as a top dressing.
- Horse manure compost must be mixed with soil in order to be an effective fertilizer.
- Use horse manure compost only when you can till it into the soil, such as in gardening applications or when tilling an entire yard for reseeding or sodding.
- Never use fresh manure as fertilizer. It harbors harmful bacteria. Use composted horse manure only.
Horse manure compost is an excellent fertilizer when used in applications when it can be mixed into the soil, such as in gardens. If you are tilling an area to seed an entire lawn, horse manure can be used, but it is a poor top dressing fertilizer for grass.
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New Lawns: Till Horse Manure Compost Into the Soil
If you’re planning to start a new lawn from scratch, you can use horse manure compost as a soil amendment to give new grass seeds or sod a boost. Here’s how:
- Remove all existing grass using a sod cutter or this non-selective weed killer.
- Till the soil to 6 inches in depth.
- Water the soil and wait 1–2 weeks for weed seeds brought to the surface by tilling to sprout.
- Kill any weeds that appear.
- Till the soil again, this time mixing in horse manure compost. Use 20 pounds per 100 square feet.
- Spread grass seed or lay sod.
Horse manure compost used in this manner works as an excellent natural fertilizer because it is not exposed to air. If you want to use horse manure to grow grass, this is the way to do it.
Established Lawns: Use a Natural Fertilizer Made for Lawns
Because the nitrogen in horse manure evaporates if it is spread on top of the grass, do not use it on established lawns. Instead, use a natural fertilizer designed for use on grass.
Milorganite is a natural fertilizer made from microbes that feed on wastewater. When it is spread on a lawn, the pellets break down, allowing nitrogen and other nutrients to penetrate the soil. This is a natural, sustainable product that will yield far better results for your grass than horse manure.
What Kind of Manure is Best for Lawns?
Like horse manure, all types of manure contain uric acid as the main source of nitrogen. This compound evaporates if it is not mixed with the soil, making it almost useless as a top dressing on your lawn. This includes cow, sheep, chicken, and bat manure (guano).
To provide natural fertilizer for your lawn, use this commercial natural fertilizer. Milorganite won’t burn your grass and is not harmful to pets. Other natural fertilizers, including bone meal, fish meal, and blood meal, are potentially dangerous to pets. Do not use them in areas where your dogs, cats, or other pets may come in contact with the fertilizer.
How to Use Horse Manure as Fertilizer
Never use fresh horse manure as fertilizer on your lawn, garden, or any other area. Undecomposed, fresh manure harbors many harmful bacterias, including E. coli. You risk disease for yourself and others if you use uncomposted manure.
- Do not use uncomposted manure. It is a breeding ground for harmful bacteria.
- Use composted manure only.
- Composted horse manure is dark brown and crumbly and does not resemble manure at all.
- Mix this manure compost with garden soil for the best results.
- Manure compost is an ineffective fertilizer when spread on top of your lawn.
Horse manure is safe for use as a fertilizer once it has been composted. This is because horse manure is piled and mixed with straw and other substances, then periodically turned. The decomposition process generates heat, killing bacteria and rendering the manure safe for use as fertilizer.
Does Manure Kill Grass?
Properly composted horse manure fertilizer will not kill your grass if it is spread on top of your lawn. However, it won’t provide much benefit either. As the nitrogen evaporates due to air contact, you’ll be left with a thin top dressing of mostly useless material.
As long as you don’t smother your grass with a thick layer of horse manure, you won’t kill it. Manure won’t harm your lawn, but it won’t give your grass much help either.
Can You Use Horse Manure to Grow Grass?
Horse manure is only an effective fertilizer when it has been tilled into the soil. Exposure to air and sunlight causes the nitrogen-carrying uric acid in manure to evaporate instead of feeding the soil. For this reason, horse manure can only be used to grow grass if it has been tilled into the soil. This is only possible if you are tilling an area and growing the new grass on it from seed or sod.
If you wish to fertilize an established lawn, do not use horse manure compost. Seek out a sustainable, natural fertilizer made for lawns. This will produce much better results and save you time and money. Spreading horse manure compost on top of your lawn won’t give you much benefit, so the cost and labor will go to waste. Save that horse manure compost in your garden, where it can help your flowers and vegetables grow better than ever.