RENEGADE GARDENER

The lone voice of horticultural reason

Don’t go all nuts planting trees and shrubs this fall without submitting a soil test.

I sheepishly admit that the first few years I operated my humble little residential landscaping business, I planted some yards in the western metro without submitting soil for testing to the University of Minnesota soil lab. I’ve been telling people for years that soil in the western ‘burbs runs fairly uniformly in the 6.5 to 7.0 pH range, because that’s what the garden elders told me when I was a youngster.

My bad. Slightly acidic may be the general average, but I’m discovering that soil pH can vary greatly from neighborhood to neighborhood and even neighbor to neighbor. I’ve done three landscaping jobs in the western metro this season, took soil samples for each, and in all cases have had to drastically amend the soil to include soil sulfur to lower the pH. One yard I’m doing in Minnetonka right now has soil that tested 7.7 on the pH scale. And phosphorus levels approaching ground-glow, of course. Four years ago, a relatively straightforward job in Minnetonka, I’d have been tempted to think hell, skip the soil test. And I’d have planted ten evergreen trees and shrubs in horrifically sweet soil. Now is a great week to plant trees and shrubs, but you can plant into early October as well. So submit a soil test before you plant-the University has been sending the results back to me in just five to six days.

Don Engebretson
The Renegade Gardener