Raised Garden Bed, Part 2

After putting in the structure of my cedar raised garden bed, I have been gradually filling it with layers of compostable material along with the soil I had taken out. This is called “sheet mulching” or “lasagna gardening” and is a great easy method to enrich the soil. In its most complete form, sheet mulching includes laying down cardboard or newspapers on top of whatever is growing on the ground (lawn, etc.) without any digging required. But since I wanted to have a deeper root zone in this raised bed, I did weed the soil and dig down deeper. Autumn is an excellent time to sheet mulch because the bed will have all winter to decompose and be ready for planting in the spring.

This is a form of composting in place, so you alternate layers using amendments rich in nitrogen (called “green”) or carbon (“brown”), but it also depends on what you happen to have in your yard. A basic permaculture principle is that waste is just nourishment for another part of the life cycle. So we are taking “waste” and giving it a chance to grow food next year. We have lots of leaves in our yard, so that is an important source of “brown”, and we also live within a half hour of the beach, so we use seaweed gathered at the shore as a source of “green.” I had a chance to go to Kettle Cove on Sunday to gather a bunch.

Kettle cove beach with seaweed.

Here is my list of layers from the bottom (5 inches below ground level) up, with some photos along the way:

  • soil from the site
  • rock dust: I added some handfuls of rock dust, which adds trace minerals (I had collected a bucket-full a few years ago from a local quarry.)
Rock dust over soil in raised bed.
Rock Dust over soil
  • a bit of old seaweed, collected earlier this year.
  • leaves mixed with a little bit of grass clippings, from Margy’s leaf collecting.
  • a few branches (I remembered this from my hugelkultur adventures) These are good for water retention, slow release of nutrients—I just added a few, and then buried them in the leaves—I could have done a lot more, but also didn’t want to limit the roots.
leaves, branches
  • more soil
  • After my trip to the beach, I added more fresh seaweed, a generous layer of it: seaweed is a great source for nitrogen, potassium, phosphate and magnesium, and many trace minerals. Note, I also added the second layer of cedar planks to bring it to its full height of 11 inches.
Seaweed in the raised bed.
  • more dried leaves with a little bit of grass clippings
  • composted coffee chaff (which was in a barrel we kept next to our compost bin to add after kitchen scraps: after a couple years it composted itself!)
  • more soil
  • a couple inches of composted manure: we have a pile of it from last year, but we have to sift it because it has become full of roots.
  • green cuttings from garden cleanup.
Garden cuttings over compost.
  • leaf mould from leaves left in a barrel for a couple years
  • more leaves to top it off.

And today it is complete! The rest will be done by winter, and soil creatures and time.

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Oak Leaves

In the spring, I learned that acorns of the white oak were less bitter–and were more widely used for food–than those of the red oak.  At that time, I was walking through thousands of acorns in our neighborhood, and thinking how great it would be to use them for food.  I also walked through thousands of dried-up oak leaves, but never saw any white oaks.  You can tell the difference because the leaves of the red oak are pointy and the leaves of the white oak have rounded lobes.

This fall, there were barely any acorns. Oaks do that.  They choose certain years (mast years) to collaboratively put on a full production of acorns, and others years, not so much. This may be a rough winter for the squirrels, who grew their families large on last year’s bounty.  But imagine my surprise when I saw these leaves on the pavement during my morning walk.  You might have to look closely. White Oak and Red Oak Leaves

Amidst the pointy ones are some small round-lobed leaves.  The tree is about two blocks from my house, a smaller oak right next to a big red oak, standing in someone’s front yard. I am going to guess that it might be a white oak. I look forward to the next mast year for acorns, to see if I can distinguish them from each other, and maybe try making acorn flour.

Meanwhile, this was a beautiful autumn for oak trees. Usually, it seems, the oak leaves hang on the tree and go from green to brown without much fanfare.  But two weeks ago, they were a translucent gold to rival the maples. Today, we had our first snow storm, but the snow is spotted with oak leaves everywhere, pulled from their branches by the wind to land on top of the snow.Oak Leaf Gold