Smothering some lawn

On Friday Kevin Newman’s team did some long-overdue pruning in my yard. They cut out dead branches, pruned back our trees where they were hanging over the fence, and removed branches that had grown over our property from next door. They fed all the branches into the big chipping machine parked in the driveway. Before they left, they carefully dumped a portion of the chips in front of the garage.

A new trove of wood chips

    This puts me right where I want to be. I’ve got big plans. I’m going to add a big swath to one of the shrub and perennial beds by trying out sheet composting.

    The spot I have in mind is some lawn in front of the dawn redwood (Metasequoia glyptostroboides). When we planted the tree in 1997, it was slender and just 10 feet tall. Now it’s rooftop height and wider every year, with feathery branches overshadowing the perennials I planted around its base. By commandeering some of the lawn in front of this bed, I can grow plants that need more sun than they can get under the tree’s branches. And I can forward my mission to subtract lawn.

Now covered with snow, this patch of lawn doesn't know what's about to hit

    My planting plan for the new part of the bed is still vague. I’m picturing low native plants. I’ve got time to study my ecoregion’s plant community to decide what these should be. The flower color scheme so far has been blue and deep pink. I’ll try to harmonize with the dusky pink blooms of a growing patch of purple coneflower (Echinacea purpurea) at the front of the existing bed.

What goes with purple coneflower?

    Sheet composting is the same process that happens in compost bins, but spread out over a wider area. 

Master Gardener Eve Werner, Butte County, CA, demonstrates sheet composting over lawn

The technique I’ll use is adapted from Toby Hemenway’s permaculture book Gaia’s Garden. Usually I skip recipes for “lasagna composting,” because I can make compost more easily by dumping plant waste on the compost piles as it comes. This time, though, I’m going to try the recipe to speed things up. If I just put down a layer of wood chips and fall leaves, they’d take years to decompose.

Wood chips on paths decompose very slowly

Here’s the recipe from the ground up:

1) A thin layer of blood meal for nitrogen (Blood meal powder is a byproduct of slaughterhouses. It appeals more to me than a high-nitrogen chemical fertilizer, which could leach nitrogen into the groundwater).
2) A layer of newspaper, minus glossy supplements, an eighth to half an inch thick, to smother grass
3) Composted manure for more nitrogen 
4) Twelve inches of wood chips mixed with fall leaves
5) A couple of inches of compost to inoculate the pile with soil organisms
6) Two inches of clean straw that’s free of weed seeds

    It’ll take a couple of years for soil organisms to weave through these layers and convert them into rich soil. I can plant seeds and seedlings this year in pockets of compost. 

Tomatoes planted into sheet compost-photo Natureln

Bigger plants will wait until next year. Meanwhile I can gloat over the lawn decomposing underneath.