I was talking to a person about planting this year’s garden and told them to compost the garden, then mulch heavy. He looked at me like I had 3 heads and asked, “isn’t compost and mulching the same thing?” It hit me that the 2 processes may not be understood by all. So, let’s talk about mulch (mulching) and compost (composting).
Compost is nutrient rich and full of life that improves the soil and feeds roots. For people that till, this is what they till in the ground, but generally, they don’t lay it on the surface of the soil.
Compost is what growers like to make by following compost rules to assure that the right bacteria grow and break down organic matter. When done right, the compost will conduct heat that will kill bad bacteria and most weed seeds.
If you have a small homestead learn how to make small batches of compost here: https://pmnlive.wpengine.com/2017/01/12/small-scale-composting/
Now, mulch is used to keep consistent moisture and keep weeds (plants you don’t want growing in an area) down. It insulates the soil, makes for low maintenance walkways, and keeps precious topsoil from run off. Mulches can be plastic (synthetics), stone, wood chips, rocks, straw, grass clippings and even paper.
This part can be a little tricky if you are new to gardening. You cannot use mulches in place of compost, especially if you are tilling. What I mean is that you would not till in stone, wood chips, rocks and such. Even if you don’t till, adding these common mulches overtime will not act like compost, not typically. These mulch options should be used only as mulch.
Compost can be used as mulch. Compost can be put on top of the earth and is usually done by no-till gardeners and permculturists. It’s best to make positive that the compost was well made to kill as many of the weed seeds or you will most likely have a garden full of plants you didn’t intend on.
Why would you want to use compost as mulch? Compost, again, will be nutrient rich, and as rain and snow happens, it will leach into your soil and introduce that goodness, naturally, into the earth. It will bring worms and other positive bacteria.
If you are worried about weed seed, make or bring in composted wood chips from tree trimming services. They won’t have any weed seeds and can smother out what you don’t want growing. So, I hope you can tell what should and shouldn’t be used for compost and much.
Wood mulches are commonly found in bags or you can get them by the scoop. They are usually used for landscaping, but they are of low value.
Grass clippings can and should be used as a mulch. They will smother weeds, but as they break down, they add nitrogen to the soil.
Straw is basically a grass. The benefit is that the seed heads are harvested for a grain crop which makes them good cover that won’t seed.
Stones can be pebbles, brick, or other concrete pathways. Stone should have a landscape cloth barrier, or you will have a nightmare of plants growing through your rock.
Plastic, landscape cloth
This is about the most secure way to easily hold moisture and prevent plants you don’t want growing. I find that I don’t feel right about using plastic mulches because they don’t let the earth breathe, so I prefer landscape cloth.
For more on mulching take a look at: https://pmnlive.wpengine.com/2016/01/22/mulching-with-purpose-and-precision/
Spread out the grass clippings for a few days while turning them a few times a day so they may dry out. If you add fresh cut grass to a compost pile, it will turn it anaerobic which leads to a smelly pile. This improves Nitrogen content by 10%.
Food waste should not be tossed in the trash bin. Most food wastes can and should be composted. Foods like popcorn, spices, fish, brew waste, molasses, potato peels, carrot peels, old bread, coffee grounds, tea bags, old pasta, milk, citrus waste, weeds (before they make seed heads) and even paper products that are not shiny can be composted. People say not to put meat because animals may attack your pile, but you can add them to your pile as long as it is hot enough to kill pathogens.
Not all leaves compost well! Some leaves, like oak leaves, can take years to break down. I’m not saying not to use them, but you should chop them up first or use them as a natural mulch. Pine needles should only be used for acid-loving plants like berries or not more than 10% of compost for all plants. Leaves make an amazing compost because they have minerals that normal compost won’t have. Trees have very deep roots that bring those old minerals up via the leaves that they drop in the fall. Don’t bypass this amazing source or nutrients.
manures make great compost, but not all manure is equal. Some manures like rabbit and goat manure can be used fresh. Other manures from cattle and poultry should be hot composted for a year to make usable. They are high in nitrogen and pathogens. Composting for a year kills the pathogens and makes it usable for your garden.
Vermicomposting uses worms, usually red wigglers, to eat the food and turn it into worm poop. This is a very valuable additive to soil and is safe to use fresh.
Mushroom soil is organic matter used to grow mushrooms in. Mushrooms are perfect for breaking down organic matter and turning it into great earth.
The thing about wood is that while it breaks down, it robs the soil of its nitrogen, so, if you don’t use it right, or you till it into your soil, you have some serious problems. If you compost the wood chips, till them until they fully break down, and you will have a fantastic additive for your soil. Like the tree leaves, your wood chips are full of goodness that was buried deep down in the earth and brought back up for use.
You may not have thought about the difference between mulches and compost, but there is a clear difference. Both are important and should be used properly in order to get the best results out of your garden!