Questions and Answers About What You Can Compost
What about composting leaves?
There are many recommendations that I have seen for composting leaves, putting them in green garbage bags for two years, making a leaf pile all by themselves, but I prefer a simpler way. I try to mow my leaves and then rake them onto the garden. I get a mulch with no work, and the worms and other soil microorganisms turn these leaves into great soil.
But yes, you can compost leaves — they make excellent compost.
What about composting grass clippings?
Not this lazy gardener. I leave grass clippings, right on the lawn where they fall, so they’ll feed the lawn. A significant amount of nitrogen is in those cut tips, we want to leave those if possible to feed the grass.
The only place to collect and compost grass clippings is in the South where the grass gross so quickly and there is a danger of thatch developing.
What about composting diseased plants?
The deal is fairly simple. If your plant is suffering from a soil-borne disease such as club root, then the diseased plant should not be added to the pile. If your plant has suffered from any other problem. It can be safely composted in a hot pile.
I note that the microorganisms in a compost pile will feed on the various molds, mildews and pathogens. They will simply not get them all. But most of these problems exist outside of a compost pile naturally, so we’re not really creating problems by adding small amounts of diseased material to the pile. Hot compost piles kill more than cold compost piles.
There are diseases that require living tissue to survive, e.g., tomato and potato blight, so these are fine to add to the compost pile.
Rule of thumb for beginners
- If the root is diseased, don’t add to the compost
- If it’s the tops, you’re fine.
What about perennial weeds?
Many of the very troublesome, perennial weeds require a very hot compost pile to kill them. These plants are so tough that cold compost piles simply gives them a place to grow. A simple trick is to dump all your perennial weeds (like pulled grass with roots attached) into a green garbage bag and tie it tight. Tuck the bag out of the way for a few months until the weeds are no longer recognizable or alive. Once they are truly dead, you can add them to the compost pile.
What about weed seeds?
Unless you have a very hot compost pile, do not add these. 🙂 Mind you, I don’t know anybody who deliberately adds weed seeds to their compost. Weed seeds will not be killed except in very hot compost piles. I live with this and accept I’ll have some weeds from my cold compost bins. Don’t get bent out of shape by it — instead, put mulch on the gardens to stop the weed seeds from germinating.
What about hard stems or woody prunings?
You can add these materials to a compost bin, but they will not decompose quickly. They decompose better if shredded and mixed with grass or other high nitrogen materials.
Can I add animal manure?
Manure mixed with wood shavings should be composted until the shavings have decomposed.
Household pets such as guinea pigs and hamsters don’t produce a lot of manure,and while generally considered safe, I’ve never done this.
Cat and dog feces should not be added to the compost.
Can I add sawdust and wood shavings?
These are very slow to compost; they are the ultimate “brown” or cellulose material and require significant amounts of green or nitrogen material to turn them into useful compost. Generally, we say don’t add them to compost piles.
What about tree trimmings?
Tree trimmings that have been chipped make an excellent mulch. As a mulch, they will slowly break down into compost. Frankly, I try to get as much of this free material as possible.
You’ll often see “Green ingredients” recommended for compost piles. Here’s what that means and what they are.
Green ingredients are quick to decompose and are high in nitrogen
- Urine, diluted with water 20:1.
- Comfrey leaves, nettles and grass clippings.
- Raw vegetable peelings.
- Tea bags, leaves, coffee grounds.
- Young green leaves or weeds, avoid plants with seeds.
- Soft green pruning.
- Animal manure.
- Grass clippings from lawn
- Poultry manure.
Similarly, “brown ingredients” have their role in the compost cycle.
These are carbon rich or slow to decompose materials.
- Cardboard such as cereal boxes and egg cartons
- Waste paper or junk mail, I personally enjoy shredding income tax forms.
- Cardboard cubes.
- Glossy magazines. While these compost is often better to recycle them than compost.
- Newspaper. This is the same as for glossy magazines.
- Any bedding from veggie-eating pets such as rabbits or guinea pigs.
- Tough woody clippings. Note these will compost faster if chipped up with a shredder
- Old bedding plants.
- Sawdust or wood shavings.
- Leaves in the fall.
- Other things you can compost.
- Very small amounts of wood ash. Very small.
- Crushed eggshells.
- Natural fibers such as 100% wool or cotton