Author Pat Welsh at her home in Del Mar

Childhood experiences in England demonstrate composting as an easy, beneficial way to recycle organic waste, but in San Diego County the author encounters drought, animal pests, and the concerns of neighbors. Ancient compost piles were rubbish heaps where organic materials rotted slowly; modern hot compost involves layering materials, keeping the pile damp, and tossing and turning it. The author has also tried surface composting, direct burial, and French trench composting.

All was well for a few years until disaster struck: Tree roots invaded the trench. While I was busily composting and raising vegetables, a friendly family of industrious scrub jays were gardening, too. Their major interest was planting Torrey pines from seeds, and they were hugely successful. Within a few years, lovely but invasive Torrey pines grew from small saplings to massive trees, slunk their hidden support mechanisms into my composting trench, slurped up all the moisture, and filled the pile with a mass of wiry roots. Overnight, my compost dried out completely and stopped rotting. The vegetable garden soon followed suit, and I had to move it as well. Finding my slow, French trench compost process ruined, I shed a silent tear and moved the pile to a new spot, hidden behind a hedge. Within a couple of years, roots invaded and again ruined my compost. In this new composting area there were no trees. This time the culprits were the invasive roots of shrubs and vines.

No other likely spot existed anywhere else in my large garden that was not already host to invasive roots. I gave up old-fashioned, slow-method compost piles forever, and I have to admit they had attracted mice. Families of mice nested contentedly in the gentle warmth of my slowly rotting compost and raised joyous little batches of babies. Undoubtedly, these open compost piles of mine also attracted and fed some fat and happy, and probably sassy, rats. But I didn’t see the rats, and when we don’t actually see the problem, we can pretend it isn’t there. But roof rats are rife in most old neighborhoods in Southern California, and that includes the neighborhood in which I live.

Next, I switched to an expensive three-bin system. My late husband, Judge Lou Welsh, joked that I had designed the Cadillac of compost bins, and he couldn’t believe the cost. I hired a carpenter to build the bins to the tune of $500 and also bought a chipper so I could grind up our woody clippings and corn stalks. But I soon discovered that I could not make my gardener wear goggles or use a chipper safely, and to do so myself was hard on my knees. The design of this compost pile solved most problems. I had tiles placed under the bins and over them installed a thick Visqueen sheet. This successfully kept out tree roots. I had small-gauge hardware cloth nailed on the walls of the bins on all sides, including the hinged top, and I had boards installed on the fronts of the bins that one could slide out in order to toss and turn the pile and then dig out the finished product.

All this worked well, but what I had not realized was that the heavy work of lifting boards and lids and tossing and turning was too great for my replaced knees. I tried to get my gardener to do the tossing and turning, or to keep the pile damp, but he appeared to think I’d gone stark raving mad, or maybe always was. A final blow was the discovery that, though this properly constructed and well-maintained bin system kept out rats, it nonetheless attracted them. This time, I actually saw them running across the top, sniffing around and wishing they could find a way inside. Despite the difficulties and hard work, I made a number of batches of excellent hot compost in these bins before my strength gave out.

About three years ago, I went to an entirely new method of composting. A company gave me a digester for all kitchen waste called the Solarcone — or Green Cone Solar Digester — so I could try it out. This is an anaerobic, or airless, composter. Since the stuff rots without oxygen, the contents inside are smelly, but the same is true if you bury wet organic stuff in the ground. I have promoted the Solarcone to my garden classes and recommended it in the book I published last year. This contraption works well, but one must have full sun to put it in, and it is most successful in sandy soil like the soil in my garden. In heavy clay soil, one needs to dig a deeper hole and fill the lower part with gravel.

The Solarcone did not bring rats or any other kind of animal. For three years it accepted every bit of my kitchen garbage, including meat, fat, bones, fish, and table scraps, thus making the kitchen garbage disposal unnecessary. Instead of using the garbage disposal, I threw everything into the top of the Solarcone, and it cooked down in volume, so the cone never filled up. Whenever we had a few hot sunny days, it cooked more quickly. But the Solarcone needs full sun, and in an ornamental garden, it is not attractive. Last year, I remodeled that area of the garden, so I had to empty it out. I asked my workmen to bury the remainder of the smelly contents and remove the cone. The plants where they buried the contents of the Solarcone are now going crazy with growth. Unfortunately, I had no other sunny spot in which to put my Solarcone, so I gave it to a neighbor who is using it now.

Last year, I sent for a two-compartment Jora drum composter for the vegetable garden only. Drum composting works well if one follows the directions available on the internet or arriving with the composter. (No directions came with the Jora, and it is not easy to put together. The men working on my garden remodel did this job.) The process begins by filling the drum with layers of half nitrogenous and half carbonaceous waste — bagged rabbit litter or sawdust is handiest and can be kept next to the drum. An important point is that one needs two drums, so while one of them is cooking, the other can be emptied out and refilled. The Jora is a good type of drum composter because it’s well made, not flimsy plastic as are some other two-compartment types, and because it contains two compartments that are unaffected by climate. Jora is the type of composter used by everyone in Sweden. Each of my daughters own and use a Jora composter to make excellent compost. (I recommend taping fly screen over the ventilation holes and also covering it with a sheet of plastic in the event of rain.) Other drum composters work, but one needs two of them.

I am now also using another homemade kind of garbage-disposal system, which slowly adds kitchen garbage into the ground, like the Solarcone, but it would work better in sun. I got the idea from a woman whom I interviewed about 30 years ago. This woman was a creative gardener who had an organic vegetable garden in a suburban neighborhood. She said an uncovered compost pile was not practical for all the reasons I have outlined here, and this was long before drum composters arrived on the market. This gal’s creative solution to her compost problem was to cut the bottoms off six plastic trash cans and bury them almost up to the top in a row in full sun next to her extensive vegetable garden. She kept the covers on them and did all her composting inside, just letting the stuff rot slowly. When the last trash can filled up, she dug out the first and started over. She had successfully used these bins to digest all her garden and kitchen trimmings for many years.

Taking a leaf from the book of this smart gardener, with a sharp knife I cut the bottom off a large plastic trash can and asked my gardener to dig a hole in the ground of the same circumference. I then sunk the bottomless trash can into the ground with only about a foot on top exposed. I now throw all my kitchen waste into this and keep it tightly closed with a bungee cord over the top. It does not attract rats, raccoons, or any other kind of animal. Though my homemade anaerobic composter is filling up quicker than the Solarcone did — the Solarcone accepted everything for three years and cooked it down to almost nothing — the trash-can system also works. It gradually liquefies kitchen waste, just as the Solarcone did. We had much cool weather last winter, but on one hot and sunny day, the materials inside the trash container dropped a foot and a half. So, then I knew it was going to work. My homemade trash-can composter fills with kitchen clippings more quickly than it would for most people, due to the fact that I begin each day with a large glass of fresh-squeezed organic orange juice. After squeezing the oranges, I slice up their peels into narrow pieces. They don’t rot as rapidly as other organic materials, especially in an anaerobic composting system; nonetheless, when this trash can is filled up, I will start another. Finally, I have a stress-free composting system that works for me and does not attract animals. Thanks to Solarcone and my homemade buried-trash-can composter, I have not used the kitchen garbage disposal in my house for going on five years, at a great saving of power and water.

I hope this tale of many compost piles will help readers to find a composting system that works for them, without going through as many stages of discovery as I have needed to do. Nonetheless, anything that involves gardening is fun, at least for me. In retrospect, even the reversals are part of the overall adventure and pleasure of organic gardening in a Mediterranean climate. ■
— Pat Welsh

In case you missed it: Adventures of the Compost Pile, Part 1