Few would anticipate it affecting gardening, but the war in Ukraine has caused a shift in plant cultivation across the globe. As one of the largest exporters of nitrogen, potash, and other important plant nutrients, Russia plays a critical role in the agricultural sector. Without fertilizers, crop yield and quality are significantly reduced. That, in turn, directly impacts the global food supply. After the invasion of Ukraine, fertilizer prices more than doubled year over year, forcing many farmers to stop buying it. Due to lower demand, prices have started to fall in recent weeks, but that has resulted in supplies piling up and further volatility in the fertilizer market.
While it has yet to greatly affect home gardeners, the fertilizer shortage offers an opportunity to explore alternatives to synthetic plant food. Whether it’s due to short supply, increased costs, or simply to be more self-sufficient when it comes to feeding your lawn and garden, composted manure is worth considering for your 2022 gardening season and beyond.
Only Feed Your Garden What Needs
While most lawns and gardens benefit from some type of fertilizer, it’s a good idea to know what yours actually needs. Start with a soil test. Test kits like this highly rated option available at Amazon—a favorite in our tested buyer’s guide—can be purchased online and at local garden centers, or get help from your local Cooperative Extension Service.
Identifying the nitrogen, phosphorus, and potassium (NPK) values of the soil can help determine imbalances. Of course, plants require more than just those three macronutrients, and commercial fertilizers are designed to have various combinations of NPK along with micronutrients to serve different plant needs.
Synthetic fertilizers are typically more affordable, but don’t contribute microorganisms to the soil, so they don’t last as long as organic fertilizers. Synthetics generally have an indefinite shelf life, if stored properly.
Organic fertilizers contribute microorganisms to the soil that will improve the soil’s quality over time. They tend to cost more and work more slowly, but are long-lasting. Their shelf life is shorter than that of synthetics.
Composted Manure Fertilizer Alternatives
Compost—decomposed organic matter—is often considered an amendment rather than a fertilizer because it can improve the structure of soil for better drainage, aeration, and moisture retention. While compost also contains beneficial microorganisms that contribute to better plant health and disease resistance, it may not contain the specific nutrients your plants lack.
Composted animal manure is a complete fertilizer that contains nitrogen, phosphorus, potassium, and micronutrients. However, its NPK ratio depends on the source animal. Applying it to your garden makes use of otherwise waste from local livestock. While it’s readily available at garden centers and online, it’s also possible to make your own composted manure at home or get it from a local farm.
For DIYers, it’s important to thoroughly research your source of manure and allow it to decompose for at least four months to remove pathogens and odors. Not all manure is suitable for fertilizer, especially when it comes to food crops. Dog and cat manure, for example, should be avoided as it can contain toxoplasmosis or roundworms that can be transmitted to humans. Pig manure is another no-no for the garden because of its high risk for spreading disease. When in doubt, it’s best to purchase prepackaged bags of composted manure with clear labels noting all of the ingredients.
The Best Animal Manure for Fertilizer
Nutrient values vary from one type of animal manure to another. Use the following breakdown as a starting place to determine which animal manure is best for your garden.
- Cow manure is a good all-purpose fertilizer because it’s low in nitrogen, so it won’t burn plants. Because cows are ruminants, there’s little weed seed to worry about if you compost it yourself.
- Alpaca manure has higher NPK numbers than cow manure but is still low enough in nitrogen that it won’t burn plants. It’s low in weed seed because alpacas are also ruminants.
- Horse manure can be a good all-purpose fertilizer, but it tends to be high in weed seed. Slightly higher in nutrients than cow manure, it’s considered a “hot” manure and can burn plants if not aged or composted.
- Goat and sheep manure is easy to collect and use because it’s drier than cow manure. It’s higher in nitrogen and potassium than horse manure, but it’s also high in weed seed. It doesn’t attract insects like cow and horse manure, and is low-to-no odor.
- Rabbit manure is also easy to collect and is high in nitrogen and potassium, making it a good all-purpose fertilizer. It has four times the nutrients of cow and horse manure and doesn’t even need to be composted.
- Chicken manure is the highest manure in nitrogen, which is good for leafy greens, but can burn plants if not thoroughly composted for at least six months. It’s also the highest in potassium, phosphorus, and calcium. Its slow release of macro- and micronutrients has long-term benefits.
- Bat guano comes in commercial formulations high in either phosphorus or nitrogen, or an average NPK ratio of 10-3-1 in nature. Used since the 1600s in Peru, its bioremediation microbes fight fungus, soil-borne disease, nematodes, and toxic substances.
- Fish emulsion, made up of partially decomposed and pulverized fish, has an NPK ratio of 2-4-1. It should be applied as a foliar spray. The odor fades over time.