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Laidback Gardening with Robert Kourik

The double-edged sword of nature: the good, the bad, & the unbelievable

Old-fashioned fighting swords cut in both directions. The irony was you didn’t know when the other side was coming. All gardening techniques and assumptions have a double edge. One we expect and the other side is a surprise, sort of like two sides to a coin. One side remains hidden until revealed.

In reality, positive approaches to gardening can have hidden negative consequences. Likewise, socalled negative garden concepts often have a germ of the positive.

The trick to a lifetime of good, effective gardening is to stay flexible and to be willing to change with the feedback of unprejudiced observation and the guidance of modern research. Like a poorly staked tree, if you don’t stay limber and flex with the winds of change, you’ll soon stiffen into a person whose outlook is determined more by constraints than by growth. Check those assumptions, and watch out for unquestioning routine and unchanging predictability. And remember, if you don’t keep growing, you really won’t be growing.

Amending planting “holes”

Seems most articles and people in the organic gardening world still say to add a generous amount of compost to the planting holes of trees and shrubs.

Flip side of the coin: Groundbreaking (so to speak) work by Carl Whitcomb in the early 1970s disproved this oft-repeated advice. In controlled studies using percentages of different amendments (up to 40%), roots of ornamental trees and shrubs were consistently larger in unamended soils, and the textural difference between the amended and natural soil seemed to actually limit roots to the area of their amended planting holes. Organic matter in the holes also seemed to pass moisture from the planting hole into the coarser surrounding soil, leading to drought stress. Dr. Linda Chalker-Scott of the Washington State University Puyallup Research and Extension Center also agrees that amendments are counterproductive to a healthy tree planting.

I’ve weaned my trees off all soil amendments over the past decade and found by observation that fruittree growth equals or exceeds that in my previous experience. The trick is to choose only those trees with roots well-suited to the native, unamended soil. In other words, no peach trees in heavy, clay soil.