Abetting the soil cycle

I’ve learned something new from ecological garden designer Larry Weaner: soil can be too rich. In Garden Revolution, Weaner describes telling contractors that he doesn’t want to add topsoil, compost or fertilizer before he plants a meadow. They think he’s crazy to turn down traditional first steps for establishing a new landscape. His point is that the plants he’s going to be growing can outcompete weeds in lean soil but not in soil that’s full of nutrients and organic matter. Those will only jump-start invasive weeds.

Northeastern meadow plants such as goldenrod thrive on lean, dry soil

    Weaner and other ecological gardeners aim to restore and imitate natural processes. When he plants a native meadow, he works with the soil that’s present and the plants that are adapted to grow on it. How does this principle apply in my garden setting, which becomes more like a woodland every year as the trees grow taller?

The yard is starting to resemble a clearing in a forest

    Last fall I doubled down on my strategy of letting fall leaves lie on the garden through the winter. Some of those will be raked off to mix with wood chips in the sheet composting experiment. The rest will stay where they are under trees and shrubs. 

    Bagging up and sending away those fall leaves would deplete my own soil, because what the trees drew from the soil to make leaves wouldn’t be replenished through decomposition. Trees have their own recycling operation going, if we just stay out of the way. I want those leaves on the ground, and not just to provide shelter for native insects in various stages of development. They’re also there to build soil that will nourish plants and sequester carbon.

Leaves on the ground serve important purposes

     But is it possible that the leaves and the compost I spread around will make my sandy soil too rich? Not for the woodland plants I want to grow. 

     A neighbor told us that our yard was once part of a gravel quarry. That’s easy to believe when I dig through a thin layer of topsoil and hit sand and gravel. If this were an unsettled area, it would probably be an oak-hickory woodland, the most common plant community for the region. The ground would be covered with forest duff—fallen leaves and twigs that would gradually break down and become part of the soil.

What the yard would look like without human intervention?

    In my garden I want to foster this soil cycle that converts leaves to humus and back to leaves again. The natural system will maintain the right nutrient balance.

    Over the years I’ve focused hard on making compost, and I still love the idea that you can turn garden waste into something great for your soil and plants. But by moving dead plants and fall leaves to the compost piles, I’ve been taking them away from where they’d otherwise decompose in place. Then I have to load compost into the wheelbarrow to replace organic material in the spots I removed it from. That’s starting to seem foolish.

Why carry compost ingredients to the pile and back?

    By letting the leaves compost where they fall, I hope to imitate the natural process more closely—and save work, too.

Witch hazel is blooming. Can spring be far off?

I'll be away for two weeks. See you the week of March 18.