AFTER the bulldozers had cleared the trees for a garden site alongside our cottage here, I learned firsthand why New England farmers packed up in droves and headed for the Midwest a century ago. It wasn't merely the paper-thin layer of topsoil, disappointing as that might be; far more disheartening was the number and size of rocks that lay barely inches apart immediately below the surface.
Digging the first moderate garden bed took the better part of a morning. And with every rock removed, the hay-bale culture of Europe seemed more appealing.
If English commercial growers could plant tomatoes directly into bales of hay indoors on the concrete floors of greenhouses, then surely I could raise them outdoors on stony Maine soil. The no-digging aspect was too appealing to ignore.
Building the hay bale garden beds was relatively simple, and we were able to have a far larger garden last year than we would have by simply gardening the conventional way.
The hay bales were a most successful experiment, too - my wife rated it our most productive garden yet. Along with the tomatoes, the cucumbers and the winter and the summer squash produced in amazing quantities, though the potatoes yielded in more moderate quantities.
Some people have made hay gardens by spreading 6 inches of soil on top of the bales before planting them in the conventional way. I adopted the English greenhouse method, in which holes are punched into the bales and then filled with soil.
The method is straightforward:
1.Place the bales side by side and water them until they are thoroughly soaked through. If you can buy spoiled, partly decomposed hay from farmers, so much the better.
2.Liberally sprinkle nitrogen-rich fertilizer or an inch-thick layer of manure on top. This is done to stimulate the decay organisms and get the composting process under way. In fact, using this method you will be making a compost heap and a growing bed at the same time. I used Nitro, a 10-0-0 fertilizer made from leather tankage on my hay bales. Blood meal or chicken manure would prove equally effective.
3.Using a pry bar or thick, pointed stick, punch planting holes in the bales 3 to 4 inches wide and about 12 inches deep. Place fertilizer in the bottom of the hole and fill it with a rich garden loam. I used Ringer's biological vegetable fertilizer in the hole and topped it with a compost-soil mix. In effect I made vertical soil columns in the hay bale to support the seedlings until they started drawing nutrients from the decaying hay.
Most experts recommend that two to three weeks elapse between making the hay bale bed and planting. This is to give the composting a head start and is the preferred way to go.
I didn't have the time for this luxury, so I sowed the seeds and set out the tomatoes right away, with no noticeable adverse affects. Possibly this was because I used a slow-acting nitrogen fertilizer on the bales. Fresh manure or blood meal might have sparked a more vigorous reaction in the bales, making them too hot for the seedlings during the first two to three weeks.
Initially I had to water the hay bale garden more frequently than the adjacent conventional bed, because the hay drained so rapidly. But after about four or five weeks, the decaying hay absorbed and held water readily. Moreover, by this time some of the roots of the plants had moved into the soil below the hay - soil that remained consistently moist. At the same time, the roots were still able to draw on the nutrients as they leached down from the composting hay.
In any event, during some hot dry weeks in August it was noticeable that winter squash, planted the conventional way, drooped far sooner than its hay bale relatives.
This coming season I plan to wrap black plastic around the sides of the hay bale garden to prevent irrigation or rainwater from wasting away out of the sides of the bales.
In his book ``Designing and Maintaining your Edible Landscape'' (Metamorphic Press), author Robert Kourick describes his experience with hay bale gardens in California: ``After several seasons the bales `wear out' but you will find a well-textured soil underneath their loamy remains.'' He found he could even dig down a foot with his bare hands in this now soft soil.
I expect the hay will have done much to improve the quality of my garden soil, too. As for the rocks - well, their presence will probably keep me with hay bale culture for some while yet!