Raised beds outperform rows at harvesttime

A dairy-farming acquaintance of mine once commented disparagingly about the size of a new neighbor's kitchen garden: ''He'll never grow anything worth a dime on a plot as small as that,'' he said. At the time I had to wonder what he would think of my even-smaller plot in suburban Boston.

The farmer in question has a large garden - maybe a quarter of an acre - which each year produces most of his family's vegetable needs. But then so does my 1,200-square-foot plot. In fact, I suggest that my garden outproduces his on a square-foot basis even given all the free manure he has available.

This is no reflection on the farmer's ability to grow things. He gets great results from the look of it. But where he follows the conventional one-row, one-path approach, I go in for intensive gardening where a narrow path separates each four-foot-wide raised planting bed. Put another way, I plant in blocks rather than in individual rows, which helps to eliminate many nonproductive paths.

Let's face it, if you can grow daffodils, pansies, or petunias in wide beds, there's no reason why you can't do the same thing with carrots, cabbage, and most other edible plants. Indeed, there are several impelling reasons why you should do so.

* Save space: Obviously, if you can eliminate two-thirds, or even half, the paths in your garden, you will have that much more space for planting. Assuming your paths are 25 feet long and 12 inches wide, you have only to eliminate four paths to gain an additional 100 square feet of growing space.

You could grow 100 pounds of potatoes in that amount of space with relative ease; and if the soil is very rich, you might raise considerably more.

My beds are 4 feet wide because I can easily reach 2 feet into the center of the bed. Some folks go as wide as 5 feet while others feel more comfortable with 3.

Vermont gardener Dick Raymond grows some of his produce in 4-foot-wide beds, but has many that are the width of his rake - about 16 inches. Raymond suggests that newcomers to the wide-row system might start with rake-wide beds, and then work up to wider beds as they begin to feel comfortable with the new approach.

* Boost production: In the Raymond test gardens last year 10-foot-long, 16 -inch-wide rows were tested against single rows of equal length for total productivity. The results were: onions - 28 pounds, 1 ounce vs. 12 pounds, 3 ounces; carrots - 30 pounds vs. 19 pounds, 8 ounces; lettuce - 32 pounds, 12 ounces vs. 13 pounds, 8 ounces; and cabbage - 110 pounds vs. 35 pounds, 12 ounces.

As a general rule, wide-row gardeners find that when growing conditions are good, individual plants are slightly more productive in single rows, but that the intensive wide rows are far more productive on a square-foot basis.

* Save labor: In a wide row, plants are set out so that at maturity the outer leaves touch one another. In these tight but not overcrowded conditions the leaves form a complete canopy which shades the soil and effectively prevents most weeds from sprouting. Watering time also is reduced and weeding time cut dramatically.

* Reduce water needs: The living mulch of plants shading the soil prevents water loss from evaporation. By protecting one another from drying winds and forming a moist miniclimate beneath the leaves, plants transpire less, which again reduces water loss.

In contrast, single rows of plants are buffeted by winds from both sides and there is no chance of a beneficial miniclimate forming. In hot, dry weather it is noticeable how much better plants grow in the center of the bed because of the greater effects of the miniclimate there.

Wide rows, or planting beds, are nothing really new. The Chinese have been growing food this way for thousands of years. So did the French-intensive gardeners around Paris in the last century as well as the English who were quick to copy a good thing when they saw it.

My father-in-law grew all his family's vegetables in wide beds that were also raised - and that's another important aspect of intensive vegetable production.

In most situations plants grow much better in raised soil than in flat beds. Gardeners who have adopted raised beds all seem to agree on this point. An exception would be in desert regions where it is best to grow in dish-shaped beds so that any rain water will drain into the bed rather than away from it.

One of the easiest ways to make raised beds is to spread manure, compost, and such other organic waste which you may have over the entire garden area. Then rototill it into the top 8 to 10 inches of soil. Rent a tiller for this work if you do not own one.

Now mark off your beds to the width you prefer and spade out the paths in between the beds. Remove all the top soil from the paths and throw it onto the beds. This way you will be lowering the paths and raising the beds at one and the same time.

If your soil is a good loam or somewhat on the heavy side, you can simply form the raised beds into gently rounded mounds. My soil is very sandy so that erosion was a minor problem for the first several years in which I gardened this way. Two years ago I enclosed the raised beds, using old boards, and can now grow plants up to the very edge of the bed.

Once the beds are raised, never, never step on them. Part of the success of intensive food production lies in the soft, cushionlike nature of the soil, which allows air and water to penetrate easily and roots to go where they want to go without a struggle.

Maintaining a fluffy soil is much more than simply a mechanical digging operation. Organic matter, in the form of compost, manures, leaves, and the like , must be added every year to maintain a satisfying level of humus in the soil. Humus is the final and most durable stage of decayed organic matter, sometimes referred to as the ''fat of the land.'' It not only improves the soil structure, but it also makes plant nutrients more readily available to the searching roots.

You will know when your soil is adequately supplied with humus and decaying organic matter when every turn of a spading fork reveals several earthworms. Don't look for the worms at the height of summer because they sometimes burrow deeply to escape the heat.

In deep, soft soil that is well supplied with nutrients, plant roots will go down in search of moisture and food rather than spreading wide and competing with their fellows. This is the key to successful intensive gardening. I add compost or fertilizer (sometimes a little of both) to every planting hole. In addition, compost is spread around the base of each plant to a depth of one inch if I have enough. A shredded leaf mulch goes on top of that once the soil has adequately warmed up.

Several books are available on intensive gardening. Two new and very good ones, in my opinion, are Dick Raymond's Joy of Gardening (Charlotte, Vt.: Gardenway Publishing Company) and Jeff Ball's The Self-Sufficient Suburban Gardener (Emmaus, Pa.: Rodale Press). An older but still very useful reference is Duane Newcombe's The Postage Stamp Garden Book (Los Angeles: J.P. Tarcher Inc.).