Herself's Houston Garden

Conservation through cultivation

Proper mixes speeds up your compost




There are several ways to compost your yard waste. You can lay it down as mulch on top of beds. You can grind it up with your lawnmower and leave it on the lawn. You can lay it down between raised rows in your vegetable garden. Or you can use a mulching bin.

You want your compost pile to break down aerobically, which uses oxygen. This will prevent odors, and waste from bacteria will be released as heat, speeding up the process and killing weed seed.

If it breaks down anaerobically ( with out oxygen ) it will be releasing methane and it will smell bad. Not much heat will be generated in the pile and weeds will not be killed off.

Compost activators are a waste of money. Properly built compost piles will reduce very quickly on their own.

The carbon to nitrogen ratio is important for maintaining heat and speeding up the breakdown of the leaves and grass, etc. You want a ratio of 30:1 Carbon to Nitrogen. A 30:1 ratio will give you a temperature of about 160’F, 40:1 tops at about 140’F and 60:1 tops at about 120’F. You want a temperature between 110′-150’F. Over 160’F and you kill off the bacteria making your compost, less than 110′ and you don’t kill off weeds and it will take longer to decompose. The proper ratio is achieved by mixing brown and green material in equal weights.

Carbon is found in brown stuff; dried material, fall leaves, corn cobs/stalks, paper, straw, pine needles, newspaper, sawdust etc.

Nitrogen is found in green stuff; eggshells, fruits and vegetables, grass clippings, manure, coffee grounds, meal and garden trimmings. (* note: I’m told if you heat your eggshells first they won’t attract fire ants. If you do get fire ants pour some boiling water on them. )

Do not use: Meat, fish, fats, or dairy products. Weed seeds will be killed if you get the pile to a nice hot temperature excepting grass runners. They will survive so do not add them to your pile.

Turning the pile is not necessary but will speed up decomposition and help heat the pile up. The more you can turn the pile the better. If you turn the compost pile every three days you should be able to reach 160’F, every 10 days 140’F, and once a month will only get you to about 120’F.

The amount of moisture in your pile is extremely important. If you grab a handful and squeeze it should not have water running out, nor should it be so dry as to crumble. Try to keep it about the dampness of a well wrung out sponge. Too much water you gt anaerobic conditions turning the pile sour. Turn the pile after a rain storm. If we are getting lots of rain, cover the pile.

Smaller particles break down faster due to their higher surface area. But keep a variety of sized material in your compost bin. This helps to keep it from packing down and allows air to circulate. You can shred material before adding it to your compost bin.

In the beginning bacteria do most of breaking down of the waste material. As it breaks down and cools down fungi step in to help followed by protozoa. Lastly we have your larger critters like earth worms helping.

You can just pile up your compost or you can use a bin. Any bin will work, just use what makes things easiest for you. You do want it to be a minimum of 3’x3’x3′ or you won’t get a heat buildup. It does not matter if you put your bin in sun or shade. Don’t set it too close to your home or fence however. Set the bin on bare ground and make sure you can reach it with a garden hose.

To build the pile:

Wet ground with garden hose

Add about 6″ of brown stuff

Add about 2″ of green stuff

Mix and water — it is very important to water as you go

Repeat

The pile will heat up and shrink as time goes on. You can add new materials to the pile as you get them.

Use hot pepper flakes to keep raccoons and other critters out of the pile.

Finished compost is dark, crumbly and no longer heats up.

If the pile smells bad it is either too wet or needs more air. If all else is well but only middle is warm the pile is too small. If all else is well but it is not heating up, add more green stuff ( nitrogen ).

If you add compost to your plants before it is done, then it will use the nitrogen in the soil. You will need to add more nitrogen for your plants use.

More information:
How to compost