STONE MULCHING IN THE GARDEN
J. I. RODALE
RODALE PRESS 1949
Chapter 6: The Stone Vegetable Garden
In an earlier section of this book I mentioned an observation of Joseph A. Cocannouer, in his valuable Tramping Out the Vintage, about how the Bavarians spread stones over the ground between the rows of growing crops for the purpose of preserving soil moisture. I thought of thee Bavarians and their stones often.
Our countryside is full of stones to be had free for the hauling. One day in thinking how I could experiment with Faulkner’s plowless method of gardening, the thought occurred, why not combine both ideas – rocks and plowless gardening.
We had made an essay into Faulkner’s theory a few years before, but in merely discing the land the weeds had sprung up stronger than the crop seeds. Plowing permits your seeds to sprout ahead of the weeds. This experiment had been a disastrous failure, but others with different soil conditions have had success with plowless farming. There is no question that keeping your best surface top-soil always near the surface has numerous advantages. In a few days we were hauling stones and laying them down in neat rows, the stone sections being about two feet wide and the soil section being about eight to ten inches. These were not going to be used in the Bavarian manner but were to stay there permanently, thus canceling forever the need for plowing. The only cultivation would be in the rows, which would get a vigorous stirring before each planting.
- Before putting down the stones we applied a generous dressing of compost and built up the level of soil in the rows with soil and compost.
- We made one serious mistake. We should have given the land one farewell plowing.
- Stones should be dug into the ground a bit so that the flat surfaces show up to be neat and flat, affording a pleasure in looking at it.
I am not suggesting this stone method for farmers or truck gardeners, but believe it has splendid possibilities for those who have the room for it and a copious supply of stones. The labor in handling and laying the rocks is not small, but since the advantages and labor reduction that will accrue in the years to come will be so considerable, it will pay an eventual handsome reward. One can work it on a five-year basis, putting in a section each year. Stones can be gathered in the fall, when the gardening season is at a low ebb, as well as in early spring before the gardening springs into action. With one of these gardens you become independent of the plowman, and do not have to worry about a wet spring which retards plowing. Nor do you have to sit and wait while the plowman seems to plow everybody else’s garden but your own. You are way ahead of the neighbors.
- This stone vegetable garden is ideal for Mr. Lazyman, for weeding is pared down to a minimum.
One of the principal advantages is the conservation of moisture under the rocks, and for this reason such a garden should be ideal for arid country. Moving air over ordinary garden soil tends to dry it out easily. In a rain more of the water is caught, due to the presence of the stones. Less of it washes away. The stones also precipitate more dew, as well as prevent the hot sun from reaching the roots.
The stones create a temperature underneath of at least 10° higher than the outside surface, which is an extremely important factor in early spring and late fall, thus adding to the growing season. It encourages the microbes to multiply. The stones themselves retain heat, and in the spring I noticed tomato seedlings bent over toward one side, apparently hugging the stone to garner a bit of warmth. One of our readers, Cora Barnett of New York City writes, “In Japan I noticed in so many little vegetable gardens, a sizeable stone somewhere near the middle. I asked the purpose of the stone and was told it was for heat, as it absorbs during the day and gives off at night.”
As an erosion preventative it is ideal. It stops ordinary as well as sheet or wind erosion. In fact such erosion is non-existent. It is ideal for use on steep or inclined land, where ordinarily one would fear to grow a vegetable garden because a heavy rain would wash soil down by the bucket-full. The stone-garden plan on an incline is a natural method of terracing, as the dirt rows between the stones become pretty level. Some of our garden is on mildly inclined land which was out of use for that very reason.
- The aeration under a stone is better than that of the open ground or sod. The conditions under a stone, its darkness and warmth, stimulate biologic life.
- The bacteria multiply prolifically. The earthworms, beetles and other insects thrive. The sum total of all their activities shows up in a nice granular surface of the soil.
- The miracle of it is that the biologic life under the stones will improve from year to year and eventually create a condition of fertility that will be as near perfect as it is possible to attain.
The earthworm, or earthworker as we should by right call him, is the principal actor in this little underworld drama. There is an affinity between an earthworm and a rock. Pick up a sizeable rock in a field and your chances of seeing an earthworm or two right on the soil surface is very good.
- The earthworm likes the darkness, moisture and warmth under the rock, but in addition, he actually chews on it.
- These very conditions – darkness, moisture and warmth – make the hardest rocks break down and crumble underneath, ever so slightly to be sure, but sufficient to furnish food for the earthworm.
This little soil digger, thus through his castings, distributes some of the mineral matter of the stones through the ssoil. It is known that the earthworm has a triturating mechanism in his digestive system which can completely break down small stone particles. As the years go on, the action of the elements will make the stones weather underneath, thus furnishing the soil a valuable mineral amendment. A wide array of kinds of stones would thus be much more effective than a dressing of ground limestone which comes from one quarry and is thus more limited in the number of mineral elements. In our stone garden there are a dozen kinds of rock including limestone, granite, sandstone, gneiss, etc. There is a sufficiency in them of practically every kind of mineral needed by the soil.
- Just as the earthworm likes a stone, so do roots. The roots of plants may place themselves alongside of pieces of rock, and by their action derive some nourishment from them.
- These roots contain organic acids which act with much vigor upon mineral substances. Humus in the soil in its processes of decay gives off numerous organic acids.
- In this stone garden you can more easily control succession planting. You also can more easily regulate the amount you need for your family. There is something about the stone rows that makes a better yard-stick.
- In this garden, you not only get in weeks before your neighbor but you do away with the weary chore of spring spading.
- Every row and section is numbered so that you can rotate crops year to year.
- The asparagus bed will find a secure home in the rock rows and stay put.
- We started 14 rows of strawberries last fall. Harvesting is marvelously simple. You can control the acidity or alkalinity of each row. When we made our strawberry bed we brought in acid soil from the woods and there will never be an application of lime there. We will dig in from time to time thoroughly decayed acid leaf mould.
- Turnips, parsley and watermelons prefer an acid soil. Our Vegetable Pocket Guide tabulates plants with the lime preferences.
- We had steady rain of three days duration and when it stopped I went into the garden immediately and began weeding. In neighboring gardens they didn’t dare enter for three or four days.
- This method is a great time-saver. You limit your self to working in only eight or nine inches of row.
- It is in the row that you put most of your compost so that as the years pass, it will become extremely rich. The ground there should become a marvelous seedbed for starting plants.
Sir Albert Howard in his Agricultural Testament explains how he witnessed a condition of infestation of aphids in plants, which seemed to be spotty. The aphids were present in some rows and not in others. When he investigated he discovered that where they were present the soil underneath was extremely hard but where they were absent, the soil was softer.
- The general beauty seems to be enhanced if one confines oneself to low-growing vegetables.
- When the head of a big system of parks saw the amazing one-year growth of asparagus in the stones, he went home and immediately put out a new bed of asparagus in a rock setting.
- In Part Two will be reproduced a few articles that have appeared in Organic Magazine, written by persons who have applied rock mulches of various kinds.
Chapter 7: The Vegetable Rock Garden by Raymond Green
Chapter 8: My Rock Orchard by Robert E. Baum
Chapter 9: Pot-Holers and Rock-Pilers
Chapter 10: Rock Mulch by John C. Gifford
Chapter 11: Increase of Earthworm Activity through Rock Mulching by Herbert Clarence White
- During the past eight months since that article appeared, some very interesting, if not startling results have been observed by this writer, especially with regard to the tremendous increase in the earthworm population and activity under the fruit trees and grape vines where the rock mulches were applied over the heavy leaf mulches.
- My three-inch leaf mulches were disappearing as if by magic. Whereas in the Boysenberry patch it took nine to ten months for the earthworm population to devour the three-inch mulch, under the rock mulches the same amount of leaves vanished completely in only sixty days.
- The conditions created by the presence of these cobblestones, stimulated earthworm activity by at least 500%.
- On average it takes about 15 minutes to remove the rocks, apply the leaf mulch and restore the rocks to their former position on top of the leaf mulch.
- The extra time employed in gathering the raw materials and applying these leaf-and-rock mulches is largely, if not wholly compensated for in saving both the time and effort in the after-care of the orchard.
- First in importance to the California gardener is the saving in irrigation. The problem of weeding is automatically solved; no weeds will grow through the heavy leaf-and-rock mulch.
- The problem of fertilizing the orchard is largely solved, for the earthworms convert the mineral-rich leaf mulches into water soluble plant food and distribute it where the feeder roots can take it up most readily.
- The large earthworm population also cultivates and aerates the soil without the danger of disturbing the tender feeder roots near the surface.
- Last but not least, is the large degree of immunity conferred upon the trees and vines thus treated, with the consequent saving in time and materials for poisonous sprays, as well as expensive spraying equipment, which in many orchards has reached an all-time high.
- The soil thus enriched seems to impart a keeping quality and extra flavor to the fruit, not found in fruit that has been grown in soils that have been poisoned by artificial fertilizers and lethal sprays.
- Sound cell structure in tree and fruit also results in a remarkable ‘resistance’ to virus and fungous diseases, and most remarkable of all – a large degree of freedom from insect pests of every description.
- The crowning achievement in this little experiment came when I discovered up to three inches of pure, black, velvety earthworm castings under my trees that had been rock-mulched. Three inches of castings in only four months!
- I am still a bit breathless over this latest discovery. Twice the results in one-third of the time! That is a 600% gain over the results obtained in my Boysenberry patch, as reported in the June issue.
- As I write these lines I am getting a bit dizzy, for if the statisticians are correct, a single one-inch layer of topsoil over an acre of land will weigh approximately 428,571 pounds. Three inches of earthworm castings over an equal area will weigh 1,285,713 pounds – nearly 643 tons of topsoil – rich neutral colloidal humus, the finest plant food known to agriculture in only four months!
- The remarkable thing about all this is that these results were obtained without ‘planting’ one domesticated red manure worm, or a single wild grey worm in the soil. They just ‘moved in’ when I provided simple living conditions and good food in the form of elm and oak leaves.
- According to statistics from the Government Experiment Stations, and confirmed by leading scientists, the soil which passes through the bodies of these little animals is somehow miraculously changed in both texture and quality. Minerals ‘hidden’ in the soil, which are unavailable for plant nutrition are suddenly released and made available.
- It has been demonstrated that earthworm castings contain 300% more magnesium, 500% more nitrogen, 700% more available phosphates, and 1100% more potassium than the soil from which they came.
- Worms constitute a perpetual fertilizer factory; and once a large earthworm population is established in the soil, little else need be done to keep the land fertile and in top physical condition.
- As Mr. Oliver reports in his famous earthworm classic: “Most soils are deficient in elements necessary for plant life not because the elements are not present, but because they are unavailable to the plant roots. All the elements are in the soil, but which are hidden and unavailable to the plant roots, are broken down by the earthworm and made available. Man has yet to invent, devise or manufacture any machine, any solid or liquid fertilizer as efficient as the earthworm. In this invertebrate animal, Nature has a perpetual soil builder, a four-in-one creature that acts upon the soil as chemist, triturator, cultivator and distributor of plant food. Few creatures equal the burrowing earthworm as a necessity to better health and greater growth to plant and vegetable life, and therefore, indirectly it is of the utmost importance to man.”
- What a pity that modern (so-called ‘improved’) agricultural methods, through the free use of lethal sprays and poisonous chemical fertilizers result in the wholesale destruction and ruthless slaughter of these beneficient little helpers and friends of mankind.
- It would seem that in following popular agricultural procedures the American farmer and gardener is actually ‘killing the goose that lays the golden egg.’ Henceforth our motto should be, ‘LET THEM LIVE!’
- Should not a ‘Soil Building Program’ in place of an ‘Insect Extermination Program’ be the order of the day in America’s new agriculture?