We all realize the benefit of compost but if you need a lot, it can get pricey. If you are wanting to learn how to get compost for free, this guide is for you.
Free has two generally accepted meanings:
- Complete crap
- Not actually free
Almost any free item you receive is either totally worthless or comes with pricey strings attached.
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That rule does not apply to compost.
Technically speaking, compost is complete crap. It is the result of trillions of microorganisms eating, digesting, and pooping out organic material. This results in the most valuable crap in the world, except for those weird coffee beans that come from cat feces.
So, how do you go about getting free compost, and how do you decide which free stuff belongs in your pile of poop?
Let’s talk about it.
How Do I Make Compost For Free?
Totally free compost is the result of free ingredients assembled in an open pile. So, costs will arise when you have to pay for ingredients and bins.
The structure of your pile can influence whether or not you have to pay for ingredients.
If you are building an active compost pile, you will need all of your ingredients at one time. This means you will need a 4’ cube of organic material in a 2:1 carbon-to-nitrogen volume ratio.
For a compost pile made of paper and grass clippings, this means you need about 200 lbs of ingredients. If you don’t have that much organic material, but you still want to build an active compost pile, you will either need to rethink your ingredients or purchase some.
Carbon is the main bulk of your compost pile, and you will need roughly 43 cubic feet of ingredients like:
- Shredded newspaper
- Shredded cardboard
- Shredded paper
- Dead leaves
- Wood chips
If you don’t have these around the house, there are many places you can pick them up for free.
Shredded paper is hard to come by since most businesses have a professional service pick it up to prevent a data breach. Wood chips are also difficult to find for free since landscaping and lawn mowing businesses chip waste material and sell it as mulch.
Dead leaves and twigs are a tossup. The problem with picking them up from someone else is that there’s a lot you don’t know. They could have herbicide residue, which can harm seedlings grown in your finished compost.
Twigs may have also had diseases that are no longer able to be identified but can infect plants in your garden later on.
Both of these scenarios are unlikely, but it is something to be aware of. If you know the source of this plant material, it is usually available for free if you pick it up.
Contact local parks and college campuses who have large outdoor areas that need to be maintained. Ask if you can come rake for free and haul off the waste. It’s a win for them, and you can get plenty of material in one afternoon of work.
Newspaper and cardboard are probably the easiest free compost ingredients to find.
Many cities have cardboard dumpsters for recycling, and you can grab a few if you don’t mind hipster dumpster diving. Grocery stores and department stores bring in hundreds of boxes per day, and if you ask a manager for the best time to pick them up, you can grab some before they are crushed and packaged for recycling.
Make sure you get boxes that are plain, and not glossy or colorful.
Contact local newspaper offices about where to pick up extra copies. They may not have any, but they will know where the extras go and who to contact. You can also contact local zoos and farms to see where they get their shredded paper for animal bedding.
Nitrogen makes up 21 cubic feet of a new, active compost pile. The easiest green ingredients are:
- Grass clippings
- Fruit & veggie scraps
- Garden waste
- Coffee grounds
Although green material only makes up ⅓ of the initial pile, the ingredients are much more dense, and harder to find in large quantities.
Local restaurants are a great place to check for free food scraps, and hotels are a great source of coffee grounds. However, most restaurants are busy and do not understand what can be composted and what can’t.
You may pick up a bucket of “compost” material, only to find meat or bread mixed in with rotten tomatoes. Skip the chain restaurants and ask local diners or steakhouses if you can take their prep waste.
Manure is a gamble as a free ingredient. Generally speaking, it’s free as long as you go collect it. If you’re willing to spend the day mucking out horse stalls, you can get enough manure to make a substantial addition to your compost.
Manure is an awesome green ingredient because you can pile it off to the side for future additions, and it will hold most of its volume and nutrients for up to a year, unlike plant waste, which wilts and dries out very quickly.
However, manure is high in nitrogen and can contain weed seeds and pathogens. If you trust the source of manure, find a vehicle that you can use for transportation, and grab a few containers that are small and easy to lift when full.
Keep in mind that too much manure can cause nitrogen burn if it is not allowed to mature.
Grass clippings and garden waste are risky ingredients unless you know where they came from.
Although lawn mowing businesses have large piles of clippings, they are not good additions for compost due to the large number of sprays lawns receive.
Grass clippings can also have weed seeds and rhizomatous roots of invasive grass that will wreak havoc on your garden. The best source of grass clippings is your neighbors. You can easily examine their lawns and see if they are full of weeds or have been sprayed.
Garden waste is less risky than grass clippings, but you may end up with diseased material that spreads to plants in the future. This is not likely in an active compost pile, but very likely in a passive compost pile.
Find local community gardens and landscape maintenance companies, and ask if they have waste material you can pick up.
If you are building a passive compost pile, you can choose between patience and a day’s labor.
Passive compost is a pile you add to as you have material. It takes much longer to decompose, but you can start it with very few ingredients, and add them as you get them. However, as you add them, you still have to keep in mind the carbon-to-nitrogen ratio.
You need to add twice as much brown material as you do green material, so if you are consistently heavy in one and short on the other, you may need to supplement.
Since you are building a pile at a much slower rate, you only need to find a few things at a time to build a successful pile. Save a few boxes from Amazon, ask a neighbor if you can take their leaf pile, or start a compost bucket at work. Small, consistent supplements are easier to find and have a much higher chance of being free.
Use Bins To Make Free Compost
Free-range compost is happy compost. Unless you have a reason to build a bin, it’s best not to. Build your pile directly on the soil near your garden.
If you must build a bin, the easiest free method is to find three heat-treated pallets and put them together into a three-sided bin. Heat-treated wood is free from chemicals that could leach into your compost, so be sure to ask first.
Almost any local business that receives shipments will have pallets available. Some larger companies get rebates for returning them, so you may have better luck finding a few free ones if you contact smaller, local businesses.
Pallets are an easy source of free scrap wood, but you can find scraps by contacting a woodshop at a local tech school or high school, or by contacting local construction companies. However, these scraps will probably make a bin that is functional but not aesthetic.
How Do I Find Compost For Free?
It is fairly easy to find compost-like substances for free. Many cities have “compost piles” where people can drop off grass clippings, leaves, branches, and other yard waste for free. This saves the city money, and it prevents yard waste from going to the dump.
Some cities use these materials to create compost. This is a great way to recycle, but probably not the best source of garden compost. There is no way to tell what chemicals, pathogens, or weeds are included in the finished product.
Also, most community yard-waste dumps are only looking for ways to save space and money. They aren’t too concerned about high-quality compost; they just want the piles to shrink.
If someone is building compost piles on a large scale, and producing a quality product, you will have to pay for it. Many lawn and landscape businesses will compost waste materials and sell it as their custom product.
It may be cheaper than bagged compost, but it will still cost about $3/cu’, which will cover a 6’x8’ garden bed at ¼” depth.
Aged manure is another popular free compost. Manure that has been piled up and allowed to rest for a year can be safely added into your soil. Cow, horse, and chicken manures are generally safe as far as pathogens are concerned, but their manure may contain weed seeds.
The most important aspect of free, composted manure is the nitrogen content.
Aged manure is very high in nitrogen, and without a soil test, you may be doing more harm than good. Manure can also lower pH, and cause temporary nitrogen deficiencies if it was not aged properly.
If you find a farmer you can trust, use a small amount of manure in one location and test the soil after a few months. A balanced soil test and lack of weed seeds mean you’ve found a good source of free compost.
How Do I Find Cheap Compost?
Free compost is a risk; people who care about the quality will be selling the finished product, not giving it away.
However, there are cheap ways to buy compost that can save a substantial amount of money if you need to buy in bulk.
Compost is relatively cheap, even at retail price. On average, one cubic foot will be roughly $3 per bag. The heaviest recommended application rate is 2” thick. So, if you have a garden space that is 20’x20’, you will need 67 bags of compost. That’s about $200 for bagged compost, which is probably overkill in most situations.
The cheaper way to purchase compost is by the yard. For the same 20’x20’ plot, a 2” application rate is about 2.5 cubic yards of compost. Home Depot sells twice this amount for $256, with a $99 delivery fee. That’s a total of $2.64/bag, and you don’t have to transport it.
However, local nurseries and landscaping companies generally sell compost for cheaper, so it’s best to shop around to find a balance between value and quality.
Free, high-quality compost is easy to make if you can find free, high-quality ingredients. Making your own allows you to examine the ingredients beforehand, and gives you more control over the finished product.
Free compost, on the other hand, is a tossup. You may find a great product, but it’s more likely that you find mediocre compost that takes a lot of work to transport home.
If you can’t make free compost, the next best option is to buy cheap compost. Use a simple worksheet to calculate how many cubic yards you need, and then make some calls. Compost can sit for a while without losing too much volume or nutrition. So, buying extra is fine as long as you use it within the year.
Bottom line; don’t use compost unless you know where the ingredients came from. Whether it’s cheap or free, poor ingredients can destroy a garden or landscape with disease and weeds.
Once you have your ingredients, learn how to build an active compost pile, and discover how to spot the signs of unhealthy decomposition.
If you are ready to learn everything you need to know about how compost is made, read my definitive guide to composting.
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