Manure is an amazing waste product that can transform the health and vitality of your garden. There is a lot of information out there about using manures in the garden, but it can be confusing. Which type should you use for what, do you need to compost it, where can you find it?
Let’s cut the crap: manures are faeces, the end result of different animals’ culinary consumption. Which animal, what they eat and how they process their food is what makes the difference. All manures are beneficial, but practically speaking, the best manure is the one that’s easiest and/or cheapest for you to access.
This article is not discussing human, dog or cat faeces. Although these can be valuable waste products when safely composted, they need special attention and should not be used directly on edible plants. Using manure from chickens, horses, sheep, cows, rabbits, alpacas and pigs however can yield great results in the garden.
Manure, generally considered a waste product, is gold for the permaculture garden. Many permaculture systems have some sort of animal contributing to the cycle, whether it’s chooks, alpacas, worms, sheep, cows, horses, or even rabbits and guinea pigs.
When integrated, these can be of great benefit. This integration is part of what permaculture calls a closed loop system or zero waste system, where all materials within the farm are recycled continuously. The three major components of a closed loop system are soil, plant waste and animal waste. As an added bonus, animals’ collective manures have valuable nitrogen (N) and plant loving phosphorus (P) and potassium (K).
Manures are generally broken down into two types:
- Hot, from omnivores and carnivores (such as chickens and pigs). High in nitrogen and appears slimier and smelly.
- Cool, from herbivores (such as cows and horses). Has a mild odour and is dry and crumbly with bits of organic matter visible.
All hot manures need composting and/or ageing so that their high nutrient content doesn’t burn the plants. Cool manures can be used directly into the garden but do benefit from a month or so of ageing. Even though alpacas, sheep, goats and rabbits are herbivores, their manures are nitrogen-concentrated in pellet form and therefore need composting or ageing before being used (unless collected with carbon rich bedding which ensures a balanced carbon:nitrogen ratio).
Buyer beware: What goes in, must come out, so be aware of the source of your manures. If stables or farmers are using antibiotics or have recently wormed their chickens, horses or cows, you’re best to avoid it (even if it’s free).
Apply composted manure lightly tilled into the topsoil preferably a week or so before planting and at key growing stages so your plants take up the nutrients.
Balance is key. Too much manure can make your soil acidic or make the garden nitrogen heavy. Be aware that high nitrogen levels will make for quick growth but weaker plants, more susceptible to attacks by diseases and pests.
AGEING VS COMPOSTING MANURE
Ageing manure simply means letting it sit and dry out. Over time the nitrogen content converts and gasses off, leaving the manure cooler and more plant friendly.
Composting, in contrast, is layering the manure with alternating layers of a carbon-rich materials (such as leaves, straw or grass clippings) and keeping it moist and aerated until the pile decomposes into crumbly black earth.
Hot composting effectively kills weed seeds (passed undigested through a horse’s stomach) and pathogens but must reach a temperature of at least 60-70 °C. The humus created by hot composting is laden with millions of beneficial bacteria that assist in the uptake of soil fertility via the roots of the plants.
THE MOST COMMON MANURES AND THEIR USES
Chook manure can be collected from chicken owners or bought from commercial outlets.
It’s highly prized as a fertiliser as it’s very high in nitrogen and other nutrients. However it must be aged and/or composted to prevent burning or even killing plants.
Use a ratio of 1 manure: 4 carbon-rich material (such as straw, dried leaves and shredded paper) for a balanced compost. Phosphorus is an important nutrient for your flower and fruit development, and poultry manure has a higher phosphorus content than the other manures.
Chook manure (and all other manures) can also be used as liquid fertiliser. With chook manure, add a cup or so of manure to a 7 litre bucket and leave it for a few days to leach the nutrients out of the manure. Give it a stir each day and when it’s the colour of tea, dilute 5:1 with water and use on the garden. It’s particularly good for young seedlings in its diluted form and is best applied in spring and autumn. Err on the side of weaker, so as not to risk burning the plants.
Horse manure has a higher nitrogen and nutrient rate than cow manure, but unlike chook manure, when it’s dry it can be directly applied to the garden as it has a balanced carbon to nitrogen ratio of 20:1.
Fresh manure should be aged or hot composted, as horses don’t digest weed seeds but pass them straight through. Horse manure is generally quite easy to access through stables and horse riding establishments, bags for sale on the side of the road, rural areas or commercially in a garden centre.
Be aware that horse manure collected from stables will be much higher in nitrogen than paddock manure as it will have urine concentrate too, so it must be composted. You also have to be careful about horses being wormed and what effect that can have on their manure, so if you’re unsure, ask at the stable.
Like horse manure, cow manure already has the 25:1 carbon to nitrogen ratio. It’s wonderful as it can be directly tilled into the soil without the worry of over fertilising, but again ageing it for a month or so is optimum.
Cow manure can be readily collected from dairies, farm gates or bought from commercial outlets.
While harder to collect (except in shearing sheds or sale yards), sheep manure is a gardener’s favourite as it’s lower in nutrient content so it won’t harm the plants. It can be applied as a slow release fertiliser as it naturally comes in round pellets. It contains potash and is great for improving structure to the soil.
If you aren’t able to collect it yourself, keep an eye out for bags in your local nurseries and garden centres.
Alpacas are one of nature’s great composters as they have an efficient digestive system. The nitrogen and potassium content of alpaca manure is comparatively high, an indication of good fertiliser.
If the alpaca pellets are collected with bedding, they can be spread around fruit trees as a slow release fertiliser (similar to sheep manure). Alpacas conveniently poop in piles, making collection easier, and you can pick this manure up from alpaca farms.
These herbivores produce poo with a punch, in very tidy pellet forms. Smaller in quantity perhaps but comparatively high in nitrogen, if the rabbit manure is collected with the bedding material, it should be a good balanced mix for composting.
Rabbit pellets also make fabulous liquid fertiliser, which when diluted will give the plants a valuable boost at critical times in their growth.
Rabbit manure is most commonly collected from your own rabbit hutch, or visit breeders and specialty farms.
Pig poo gets bad press because it stinks. The smell permeates everything but the manure is fantastic. Worms adore it and plants thrive in it.
Pig manure definitely needs to be composted though. Get the compost wet and hot so that it will break down and kill any organisms that may be a danger to your health.
It can be hard to find at your local nursery but if you have a pig farm near you, get stuck into it to get wonderful results.