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Urban Agriculture – Learning from Our Mistakes – Part 1

Original conceptual design for Keyhole Garden

Today I begin a series of posts dedicated to my own experiment in urban agriculture.  My wife and I have decided that we should ‘walk the walk’ on creating a permaculture-based lifestyle.  We cannot afford to add a graywater recycling system or a composting toilet.  Our house is not well oriented for solar panels either.  So our foray into practicing what I preach had to be in the garden. In posts over the next couple weeks, I will attempt to chronicle what we tried, what worked and what failed, in the hopes that others might benefit from our errors, and to lay the groundwork for our next round of experiments.







Our Gardening Goals

Preliminary Garden Design overall, with keyhole garden in the middle as first element.
Preliminary Garden Design overall, with keyhole garden in the middle as first element.

We are, thankfully, not dependent on gardening for our food.  It has occurred to me (and to a smaller extent to my wife) that one day we MIGHT need to grow some of our own food to make ends meet.  Then there is the romantic fantasy of transforming our urban and suburban landscape, currently dominated by grass and shade trees and flower beds, into a lush foodscape featuring vegetables, fruit trees and berry bushes.  Hey, if the claymation characters from Wallace and Grommit “Curse of the Were-Rabbit” can do it, why not us?















PrelimPlantingDesignThe preliminary planting plan shown here is based on the idea of ‘companion plants’.  We have a deer and bunny problem here and so we tried using plants they don’t like (daffodils, chives, onions, marigolds, and basil) to created a barrier around the other things.










Getting the Ground Ready

In preparation for planting a garden in the Spring of 2014, we needed to build the soil starting in Fall 2013.  We know that our existing soil really sucked.  It couldn’t even support grass anymore (though crabgrass still thought it was fine), let alone zucchini and squash.  So we rolled up our sleeves and sheet mulched a 13×16 patch in our back yard.

Sheet-mulch Gaia's GardenSheet mulching is intended to be a way to kill the grass and build the soil in place without a lot of digging.  We had been saving cardboard boxes all summer and even raiding the recycling piles from our neighbors.  We got started too late in the year to have compost and mulch delivered to us at a reasonable price (see Resources below for more information about how to do this), so we had to buy the bagged compost and pay a ridiculous price for a bulk delivery of mulch.  We piled this on top of the cardboard, alternating with layers of straw (for Carbon).  For more information on Sheet Mulching, see the this link or look at some of the references listed below.







13×16 area of our lawn being sheet-mulched for a keyhole garden. This is the sunniest spot in the back yard.


This shows the basic layers – cardboard, compost and straw. We threw some more compost and then a layer of mulch on top of what’s shown here.


Completed bed being watered.


My wife planting fava beans as a cover crop for the late Fall season. Fava beans help fix nitrogen from the air and (when ‘slashed’) store it in the soil.


This process created a raised area about 12 inches high, which we trimmed with plastic (and later metal) edging to try to make it neat; most of the neighbors think we are crazy as it is, I didn’t want to be labeled as hillbillies too.  The photos above show what it looked like when we were done.

Through the rest of the Fall and Winter, any leaves that we raked up went on top as well.  We planted a ‘cover crop’ of fava beans to fix nitrogen, but they were only moderately successful at growing.  We got a late start so we may try this again another year.

In retrospect (after our full growing experience to be described later), we should have tested the soil (kits are available from the garden center) and added materials accordingly (stuff like copper and potassium and bone meal).  This is our first order of business in 2015 when the ground thaws next.

Getting Things Started

Next we did the whole shopping thing, doing our part for the national economy and buying seeds for the various things we had decided to plant.  Here is a sketch of the layout we had planned as well as a list.  Seeds can be expensive, especially the shipping!  I mean, these are SEEDS, not live Alaskan King Crabs!  We bit the bullet and vowed to find sources next year that wouldn’t insist on FEDEXing us seeds from Washington State (which ironically is about as far from Washington DC as you can get in this country).

We bought several of those seed growing trays too and set up a table in the sunniest place in the house, right in front of a picture window in our library (also called the Sun Room).  Friends from Ohio had warned us that this wouldn’t cut it, but we decided to try anyway.


Diagram of our seed starting area.
Diagram of our seed starting area.


Sure enough, a few weeks later we were seeing very mixed results.  We decided to see what grow lights would do for us.  This DID help a bit, but our overall experience was that the plants were kind of anemic and spindly.  The tomatoes were pathetic and we wondered why our friends in Colorado could get so much better results in the sunny corner of their kitchen.

We are still not sure.  When we were transferring the plants to the garden, though, we did notice that the planting media looked a bit like sawdust, and maybe we needed to add a lot more nutrients than we had planned.  That will be part of our experiment in 2015.

Getting it in the Ground

Mid-April came and it was time to pull the trigger.  This time we ordered 3 cubic yards of compost and 5 cubic yards of mulch from the City of College Park, a nearby suburb that actually seems to collect organic material and make something useful from it (see Resources).  DC and most of its satellite communities are frankly a bit pathetic in this regard.  DC has made a big deal about their sustainability plans, and they DO collect a lot of leaves in the Fall (DC has a lot of trees), but it is very hard for residents to get it back as compost and mulch.  I assume that someone in the local government is making some money on the side by selling this to professional landscapers, or maybe to College Park.

For those of you who have never seen 3 cubic yards of compost, it is a LOT.  We shoveled for weeks and put 6-8 inches of compost on just about every part of our lawn (including the grass), but we still had to strong arm neighbors into taking some of it (please don’t ask what types of extortion we had to resort to).

Next we installed soaker hose connected to a hosebib on the house, using an automatic timer to help keep things moist when we were away.  More money we pumped into the economy.   We thought the sectional soaker hoses with couplers and splitters worked pretty well (see Resources list below).  The watering timer was a life-saver (literally from the plants’ perspective) in dealing with our travel schedule.   I think most people today will need them at one time or another.  Soaker hoses use much less water than sprinklers too.


Here is the bed in April of 2014. The daffodils are up and you can see some of the plants we put in. The most noticeable ones are some basic plants we bought from Home Depot, mixed in with the small ones we seeded ourselves. You can see the soaker hose here too.


We had thought about ways to use the water in our rain barrel.  Generally these will require a pump (unless you have a steep site with the house at the top and the garden at the bottom).  We did not have much luck finding a pump with right flowrate and head for a soaker hose (similar to what you get from your typical house hose bib) and at a reasonable price. We also wanted some way to automatically switch from the rain barrel to the potable water supply when the tank ran dry, and which would work with the automatic timer.  We drew this diagram, but never put the whole thing together. Ultimately, we will probably buy a pump (in 2015) to better use the water from the rain barrel, but will not try to make it part of the automatic soaker hose system.  This is certainly possible to do, but we feel may just be too expensive for our little experiment.

We carefully transferred the fragile little plants we had been cultivating inside, fed them some plant food, mulched them and waited.



Separate Lettuce Bed in shadier part of the lawn, w/ metal mesh over it to protect it from the local deer hear (more on that in later post).
Separate Lettuce Bed in shadier part of the lawn, w/ metal mesh over it to protect it from the local deer here (more on that in later post).


To be continued in our next blog entry.

Lessons Learned :

1)  Spend some time looking for local bulk suppliers of compost, mulch, straw, etc. and make sure you know when they have materials available during the year.  You have to shop around because although the materials are relatively cheap, the delivery charges can vary widely.  For those of you in the Washington DC Area, we personally recommend the City of College Park.  Distance makes a difference, so shop locally.

2) It may be difficult to gage exactly how much material you need.  We did the calculations and thought we had struck a balance between the dangers of having too little or too much, but we still had too much and our driveway was compost-central for months as a result.  The delivery costs are not linear, though, so you may decide that too much is better.  If you have neighbors that garden, pooling resources may be a good option.

3) Start looking for good suppliers of seeds.  We were surprised how little our local garden center carried in the way of seeds even when they carried the mature plants.  Many of the mail order seed houses seem to charge a lot for shipping, and are often located a long way away.  If you are doing this to be more sustainable, you need to find local sources.  We still have not done this, but are planning to start right away (may be too late as it is January).

4) Unless you have a spot that gets 4-6 hours direct sunlight a day (so one that faces directly south), there is a good chance you are going to need a grow light to start your seeds.  Washington DC is not extremely overcast in the winter, but this still makes a difference compared to some place like Denver.

5) There are some cool products designed with a sponge-like mat under the seed cups to make sure they say moist without drowning them.  We recommend these (as the ones that did NOT have the mats dried out on occasion despite our monitoring).  In retrospect, we believe that the ‘growth medium’ is pretty much devoid of nutrients, it is is just stuff to keep the plant roots in.  You will almost certainly need to add more plant food mixed with the water.  Seems obvious now, we admit.

6)  Consider using a rain-barrel with pump to do manual watering and hose-feeding.  Automatic systems are doable but much more complicated and may not be worth the added expense unless you have a very big water tank or a friend with a professional irrigation company.


Bulk Compost and Mulch – We hated the idea of buying compost that was harvested somewhere, wrapped in plastic and shipped cross-country to our yard (via Home Depot).  It is not always easy to find local bulk materials unless you are a professional landscaping company.  We shopped around, and found that one of biggest expenses was the delivery charge.  The most reasonable deal in the NW Washington DC area was from the City of College Park –


There are many good references on permaculture design.  Gaia’s Garden by Toby Hemenway (2009 – Chelsea Green Publishing Company) is one of the best references on plants and on gardening techniques, including sheet mulching.