Every summer I look out the front door in amazement at the sheer amount of green in the yard. It happens fast, growing from tiny sprouts in the cold, hard ground of March into mountains of thick stems and new fruit in July, fast forward through August’s drought into September’s harvest and back to ground level in November, under a blanket of snow. This year I have a new element in “waffle beds”; depressions dug below ground level to increase drought tolerance. I began making raised beds into recessed “waffles” back in April but the technique has really proven itself during the last three weeks of searing heat and zero rainfall. Here is the waffle structure near the front of the house, photos taken once a month from May through mid-August:
We’ve had some precipitation this month but it has come as sudden downpours of heavy rain over a short period. My raised beds never absorbed much water because the deluge simply rolled off the dry, caked soil on top – although the recessed paths on the sides (where all the moisture ended up) generally looked great after a storm. This year, no matter how hard and suddenly it came down, rain pooled at the bottom of the depression where it would do the most good. After a week of sun and August heat the bottom of each waffle, shaded by plant foliage or mulch, is still moist and friable.
I have begun transitioning the entire garden over to recessed beds, mostly waffles but with an experiment in “swale” gardening on a south-facing slope (to be explored in a different post!). There are a few places where I’ve dug to a depth of 18″ and found ledge – very common in Downeast Maine. I’m using the same process of adding good soil to the bottom of the waffle, but will track these particular beds and see if drainage becomes an issue. I’ve also made a note not to plant root vegetables in these locations just yet! It may be that I eventually build higher walls around the ledge-prone areas to provide extra depth without digging, but soil is at a premium in this garden and the experiment will have to wait for now.
Waffle beds are the opposite of the raised beds that have become a fixture in US gardens since the 60’s. Unfortunately, raised beds don’t work well in my micro-climate: mid-summer droughts make it difficult to get moisture to the plant roots, and our soil is light and sandy and doesn’t compact well in a heap. For years I’ve noticed that plants (mostly weeds) grow better in the depressions between beds but it wasn’t until this April that I began to take advantage of this. This is the first waffle bed I made almost two months ago, now full of well-grown celtuce and brassicas with a mixed cover crop around the edges.
The depression seems to have kept the seedlings sheltered from the cold winds and night frosts during our late spring. The waffles definitely increase water retention. Below are the first beds I dug near the house for our tomatoes and you can clearly see the color contrast between the dry walls and damp lower level.
The same seedlings, one week later and about twice the size. They evidently like the additional shelter and moisture, while the cover crop of Phacelia Tanacetifolia is drought-tolerant and sprouts well on the waffle “walls”. (I’ve planted 10 beds of at least 5 plants each – to the tune of 700 lbs of tomatoes as a conservative estimate of yield. Come September I may be posting extensively on tomato sauce production.)
This bed in the lower garden has been divided into five waffles: peach tree, cabbages, Provider bush green beans (still under row cover), BlueGold potatoes, and the far bed of celtuce and brassicas pictured above. Everything seems to be thriving. I’ve planted the poor soil heaped between waffles with nasturtiums and a low-growing cover crop mix, mostly to help hold the soil in place during the first year.
I’m pleased with this method so far! Next post will be on this weekend’s project: swales as a solution for “depression” gardening on a south facing slope. Here is a terrific introduction on swale gardening from Tenth Acre Farm.
What is a Swale?
Yesterday I posted a little bit of history on the evolution of raised beds in American gardening (after finding many more scholarly articles on the subject than I could have imagined) and then I went outside and did a practical experiment on waffle bed gardening by digging holes in the ground. Well, that wasn’t all there was to it, actually.
I started by digging a trench and piling the soil up on either side. I was planning to save the good topsoil to a special spot and use it to top off the eventual “waffle” but honestly there wasn’t enough to bother with. I do have a bumper crop of roots, rocks, and yellow clay.
Here I’ve finished digging the bed out to below grade. I filled the bottom layer of the walls with old firewood and the rocks (many, many rocks) that came out of the interior, then piled soil and clay on top. One of the sources says to walk around on the walls to tamp them down; you’ll want to walk on them later so it’s a good idea to make sure they’ll hold your weight safely.
I sat on one wall of the bed (very comfortable!) and planted celtuce and Brussels sprouts. The forecast is still for below freezing temps overnight this week but these seedlings have been hardening off for a few days and should be fine under row cover.
I covered the cell with wire hoops and some row cover. Now the forecast is calling for snow tonight (April 9th!) so I’m going to lower the floating row cover to the plant level and stretch some clear plastic vented material over the hoops for a double layer of protection. Fortunately I have plenty of seedlings!
As I’m writing this at 11 a.m. the temps are still hovering around the freezing mark, although it’s pleasant enough if you’re standing in full sun. I plan to continue laying out new beds but refrain from planting anything else out until next week at the earliest. Questions or feedback, let me know!