National Wildlife Federation/ San Diego County

Compost

WHAT IT IS AND WHAT IT DOES

Compost is the end product of decomposition of organic matter – in other words, it is what remains when something that was once alive rots.

Back before the ancient Egyptians, farmers were composting. Native Americans composted before the coming of the Europeans. It seems that everyone has always known that compost is good for the soil.

Compost happens because microorganisms break down organic matter creating humus. This humus causes the mineral particles in soil to clump together, improving soil structure, holding moisture in the soil, and promoting soil health.

This is what compost does for your soil:

Improves soil structure

Acts like pieces of sponge in the soil to hold moisture

Improves aeration so that plant roots can get the air they need

Holds the nutrients in the soil instead of letting them leach with the groundwater

Increases the number of microorganisms in the soil

Neutralizes acid soil and acidifies alkaline soil

Digests the spores of harmful fungi

Contains trace elements that are difficult to obtain otherwise

Destroys pathogens in the soil making plants disease-free

Helps plants resist stress and insect attacks.

HOW TO MAKE COMPOST

Combine an equal WEIGHT of greens and browns. Greens are wet materials which are a source of Nitrogen. Grass clippings, garbage, manures are all green materials. Browns are the dry twiggy materials that are a source of Carbon. Browns include straw, dead leaves, dead weeds, corncobs, etc. Simply balancing your compost pile with equal WEIGHTS of greens and browns will give you the 30 carbon to 1 nitrogen ratio that is the ideal.

The more variety in your compost, the better your compost!

In addition to greens and browns, your compost pile needs moisture and air. Your compost pile should always be as damp as a wrung out sponge. Eastern books tell you to cover your pile. In California we are grateful for every drop of water that falls on our piles, so we would NOT want to cover it. Keeping air in your pile means it is well aerated and will not begin to stink. Don’t let anyone step on your pile or compress it. Air is necessary to promote aerobic decomposition.

Ideally your pile needs to be 3’ x 3’ x 3’ but that is just an ideal. You can compost in any container bigger than a five gallon bucket.

The key to faster compost is smaller particles. The more air the pieces are exposed to, the faster the rot (oxidation) takes place. It is not necessary to own a shredder to make compost, though that certainly speeds up the process. If you have huge piles of leaves you can run a lawn mower over them to shred them to speed things up.

WHAT DOES NOT GO IN A COMPOST PILE

Meat and meat products like grease and bones and gravy

Any pet or human manure

Coal or charcoal ashes

Diseased plants

Glossy paper with colors, from magazines

Bermuda grass

Weeds with mature seeds

Sunflower seed hulls

Plywood dust and debris

Sawdust from pressure treated wood

Seeds and fronds from palm trees

Plant debris from plants that were killed with herbicides

Plastic or styrofoam



WHAT DOES GO IN A COMPOST PILE

Coffee grounds

Corncobs and stalks

Pea and bean stalks

Eggshells

Fish

Fruit wastes

Grass clippings (spread these in layers no more than 3” deep)

Hair

Hay

Leaves

Manure

Paper

Nut shells

Pine needles (they will break down slowly, they might be better used as a mulch)

Sawdust

Wood chips

Tree prunings

Seaweed (in moderation!)

Stable bedding

Vegetable waste

Green weeds

Fireplace ashes (in moderation!)


HOW TO USE COMPOST

Spread a thin layer of it on the soil around your plants as a mulch in a bed

Use it as a fertilizer and spread it on your plants

Make it into compost tea by soaking a bag of it in water for several days, then diluting it and pouring it around your plants

Mix it half and half with perlite and use it as a potting soil

HOW MUCH COMPOST TO USE

As much as you have. You can grow plants in straight compost so don’t worry about using too much!

ACTIVE VERSUS PASSIVE

Active simply means you turn the pile occasionally. Passive means you watch TV or read a book and let the pile take care of itself. Both methods yield compost eventually.

HOW TO MAKE COMPOST

Find a level site out of the way and out of sight. Think about putting it where you can get a wheelbarrow to it easily to bring materials to the pile and to haul compost away to use.

Dig a pit, or build a circle of wire, or make a bunch of fancy bins, or buy an expensive compost maker bin, or use old trash barrels or steel drums in which you have punched holes in the bottom and the sides. It doesn’t make any difference. You can also just pile it on the ground.

Assemble the browns and greens. Cut them up as small as you can one way or another.

Put a layer of twiggy dry stuff on the bottom for good aeration.

Now start making layers of greens and browns. The green layers will be quite thin in comparison to the brown layers of dry materials.

Make your layers slightly concave in the center so that the pile does not look like a mound but like a cake with a sunken top.

Sprinkle the dry layers with plenty of water as you build the pile. Spread some dirt or old compost on the green layers.

Be sure to end with a layer of old compost or soil or dry materials. You do not want to attract flies or rats or possums with garbage they can smell and reach.

If you are of a scientific mind you can take the pile’s temperature occasionally and turn it whenever it reaches 140 degrees. This is not necessary but it gives you some nice exercise.

PROBLEMS IN THE COMPOST PILE

Nothing is happening. It’s too dry or the materials are not chopped small enough. A pile of brush is not a compost pile. Try again.

Stinks. It’s way too wet and it’s gone anaerobic. Turn it and add dry materaials to it.

Fire. It was almost 100% green materials and you didn’t pay attention to it so it got so hot inside that it started smouldering. This is not likely with a home compost pile, to say the least. But if you had 12 yards of fresh green shredded tree prunings delivered, it could happen. Pull the pile down to no more than 18” in height and water it down.

Too cold. Nothing is happening. Add greens. Or the pile may be way to small and out in the open.

Flies. You didn’t cover the food scraps. Turn it again and put browns or soil on top. Put the outside on the inside.

Animals in your pile. Same thing. Cover those food scraps.

CREATIVE COMPOSTING

Just dig small trenches and bury what you would otherwise compost. You can do it somewhat like you would doubledig by digging a small trench, burying tonight’s food waste in it and covering it with the soil you take out of tomorrow night’s trench. This is a wonderful way to enrich the soil around a fruit tree. Just dig a hole at the edge of the dripline. By the time you’ve made it around the tree with your buried compost the tree will have grown and your second circle will be at the edge of the new expanded dripline. I saw peaches as large as cantaloupes that were grown using this method.

Whenever you want a new garden bed, just build your compost pile there. After a year or so, rake it down into the size and shape you want and put some rocks around it for a border. This is the easiest garden bed you will ever create, and probably the most successful.

Blend and pour. You will want an extra blender for this! Take your daily food scraps and put them through the blender. Pour this directly around your plants. Cover with a thin layer of soil or mulch.

Dry leaves and green weeds can be used as mulch directly on the soil and will eventually be decomposed into the soil by microbial action without your help.

Anaerobic composting can be achieved by following these instructions exactly! Put a mixture of green weeds and dry leaves and soil into a black trash bag. Shoot in some water with a hose to moisten it very well. Tie the bag shut very tightly. Leave it in the sun for about 4 months in the winter, at least 2 months in the summer. After it has shrunk down in mass and become somewhat lighter you can open it. It should be beautiful compost. If you opened it too soon it will stink more than you could ever believe.

If you have no room for a compost pile you can make a worm farm in a plastic tub. That’s something to discuss in another article.

SOME FINAL WORDS

A few tricks I’ve learned in thirty some years of composting are the following:

The richest soil you will have in your garden will be under the compost pile. Treasure it.

A Chinese trick for growing awesome tomatoes is to plant them at the edge of a compost pile. If your pile is rich and moist you won’t ever have to water your tomatoes while they grow.

Hog wire in a 6’ circle makes a great compost bin but it’s not very attractive on its own. It disappears and looks wonderful if you grow sweetpeas or some other vine on the wire.

IF YOU HAVE TO BUY COMPOST OR FIND IT SOMEWHERE ELSE

There is a good product on the market called Farmer’s Compost. I have bought good compost from Alpine Rock and Block on Los Coches and Highway 8 in Lakeside. You can also get compost and mulch free from the city landfills. Just take a good look at what you are getting.

Very well composted and aged horse and cow manure is good provided it is a soft brown color and very light in weight. Any fresh manures need to be composted, aged, and leached of salts before use.


Cb/01/05