Constructing My First, But Definitely Not Last, Keyhole Garden

You don’t have to live in the desert to benefit from a drought-tolerant composting garden.  Constructing a  “Keyhole Garden” is a great way to bring a creative, sustainable garden into your life, no matter where you live.

A keyhole garden is, essentially, another type of raised-bed planter. It is especially designed to work well in places that have poor soil and bad weather, namely scorching heat and elusive rainfall.  The method was “developed by a humanitarian aid organization in southern Africa, where resources are scarce and the climate unforgiving” (

With this year shaping up to be one of the worst on record for rainfall here in Central California, I’ve been taking advantage of my winter gardening “down time” to look into gardening methods that will help me conserve water and still be able to raise bountiful crops, this summer.  The keyhole garden looks very promising for helping me to do just that.

Take a look at how I constructed this drought-hardy garden…

First, I measured a 6-foot diameter circle to define the inside wall of my garden, and constructed the exterior wall using cut up timbers from dead trees that we had lying around the property.  I also cut out a small notch in the circle so that I can access the wire basket that I am going to place in the center.  (One of the principles of permaculture and sustainable agriculture is that you make use of available, recycled materials that you have on hand, rather than purchasing items from an outside source.  If you don’t have access to timbers, you could use rocks, metal, bricks, or any other material that can support the weight of wet soil).  By the way, keyhole gardens do not have to be round.  Here is an example of a 10′ x 10′ keyhole garden that I found on the web.  It even comes with a planting guide! timber exterior wall Next, I created a one-foot diameter tube out of chicken wire that is going to be filled with compostable material, like kitchen scraps, that will be placed in the middle of the garden and provide it with moisture and nutrients.  The garden will also be watered from this juncture.  Watering from the middle of the garden is supposed to force the plants to send their roots down deep and over to the tube, conserving water in the process. chicken wire tube Following that, since we have so many problems with gophers around here, I lined the entire bed with chicken wire… 100_4396 Then, I lined the bed with pieces of cardboard.  These will decompose as the garden matures, helping to nourish the soil and bring in lots of beneficial worms and insects.  I also set the wire tube in place at this point… 100_4399 Then, I followed this with a thick layer of dead leaves, which are abounding around our property at this time of year.  (When I make my next keyhole garden, I will lay down a “green mulch” layer first, though, following the lasagna garden method of alternating green and brown layers.  Green layers consist of things like herbaceous weeds, grass clippings, and animal manure; brown layers consist of things like dead leaves, straw hay, wood chips, and newspaper)… 100_4400 I thoroughly watered the cardboard and leaves, and then I added a layer of hummus (a mix of compostable materials that has not yet reached the finished compost stage) on top… 100_4402 Finally, I added a layer of top soil (taken from gopher mounds around the property, which are actually a great source of top soil because the dirt is really clean and typically weed seed-free, since it’s coming up from a couple of feet underground – who knew those guys could be so useful???) gopher holes

100_4403 Well, that’s it.  Pretty simple, huh?  All that’s left, now, is to build a ton more and figure out what I want to plant inside of them.  Any suggestions?


Learning about Soil Fertility: Putting The First Plot of Corn to Bed

We just finished harvesting our first plot of corn.  I’d call it a fairly successful attempt.  Although there were only  a handful of ears that were fully covered with kernels, due to poor pollination, and I picked them a little too late, we were able to enjoy some in a fresh corn salad, and I froze another gallon and a half for using later on in soups, casseroles, creamed corn, and any other recipes that aren’t too fussy about the “chewy” texture of this particular harvest.  We’ve got a few more plots that are still maturing in the fields.  I don’t know if I can do anything about their pollination this late in the game, but you’d better believe I”ll be keeping a better eye on them so they don’t get to the dough stage before we pick them, like their siblings did in this last harvest!

After the harvest, I wanted to make sure that I was being wise about maintaining soil fertility, so Matt and I took some time and labor to employ a few sustainability techniques I’d learned about for replenishing the soil…

First, we (okay, mostly Matt) spent some time digging out the corn plants and removing the straw hay mulch from the plot.

After the corn was removed, we lay the entire plants back down on top of the dirt.  Corn is a heavy feeder and removes a lot of manganese from the soil.  Leaving the crop residue behind after harvesting the plants allows the minerals within the stalks to decompose and return the manganese and other nutrients it feeds on to the soil.

Another technique that we’re employing to replenish the soil is immediately planting in a crop of peas, which are useful for their nitrogen-fixing ability.  Since we garden organically, we don’t spend money on expensive fertilizers, and find that peas, beans, and clovers do a better job since they require the soil to take an active part in fixing its own nutrients.  I looked for open areas between the corn stalks,  drilled a small hole, and dropped a pea in.

After planing in all of the peas,  the entire plot was covered back up with  straw hay and watered.

In a few weeks, we should see some pea shoots emerging out of the hay, like this one that’s coming up from another plot where I used the same technique after harvesting a plot of potatoes and green beans.

I know that by returning the corn plants back to the soil in the form of compost and following up with legumes to further-fix the nitrogen that most of the soil fertility will be restored in this garden plot.  Utilizing these alternative fertilizer methods will not completely restore all of the vitamins, minerals, and trace elements to the soil that are necessary for optimum fertility.  However, it is a good start towards soil sustainability and creating the permaculture environment I’m striving for.  As always, I’ve got a lot to learn, but I’m enjoying the process every step of the way!