Double-digging…ever heard of it? Although it can be quite a workout, it’s one great way to get a new garden built quickly in a place with poor soil quality. It requires no tiller or other expensive equipment. With only a spade and a garden fork (and some grunt work), you can be ready to plant in a day or two. And you can skip the gym after you’re finished.
When I started gardening with my parents many, many…MANY years ago, we kept the typical small-town backyard vegetable garden. We had a few edible perennials – black raspberries and rhubarb – but mostly it was tomatoes, green beans, zucchini, cucumbers and potatoes. Every year, the neighbor would come over with his Troybilt tiller and turn it over before we began. About every other year, we would need to add a load of manure from a local farmer, or the subsoil would get compacted and turn back into hard Iowa clay.
Later in life, when my wife and I began to garden in small plots of lousy soil in our tiny yard in Brooklyn, New York, we needed to learn some new techniques. I ordered a copy of the classic hippie gardening book How To Grow More Vegetables Than You Ever Thought Possible on Less Land Than You Can Imagine by John Jeavons, and to make a long story short, it truly transformed our lives. I strongly suggest that anyone doing small plot gardening own a copy, although you can find a free pdf online to check out before you buy.
Double digging is one of those techniques that Jeavons suggests in the book. It’s a pretty simple idea, really. There are just a few steps:
1. Lay out your new garden bed.
2. With a spade, take out a row of soil as deep as the spade. Set this dirt aside.
3. You now have a trench the width of the bed. Using a garden fork, loosen the subsoil in the bottom of the trench.
4. Add some compost and work it into the subsoil.
5. Remove another row of topsoil. Use this to fill the first trench.
6. Repeat until you get to the end. Use the topsoil from the first row to fill the last trench.
Simple, right? You have now created a good, deep bed, broken up compacted hard-pan, added nutrients and organic matter, and had the opportunity to get grass and weeds out of the topsoil.
Now, if you do a web search on “double digging,” you will find that among garden bloggers, it is currently a little bit trendy to bash on our old hippie technique. Maybe it’s because double digging comes from the old French “biointensive” technique, and nobody likes the French, right? People say that it is too much work, that it is more effective to build soil by “lasagna gardening,” using “Hugelkultur” beds or simply building raised beds on top of the bad soil. All true! And I plan to cover those techniques in the future as well.
So why am I still a fan of double digging? Because if you have nothing but a shovel and the compost from your kitchen scraps (or your vermicomposter) you can build a garden today and plant it tomorrow. It’s FREE, baby. And it’s a groovy way to hang out and commune with nature, man!
Okay, you say, enough of the hippie crap. You sound like my creepy uncle Bill. Or “Starhawk” as he likes to be called. I already own a tiller and I need to get to the kid’s soccer game by 3. Right on dude! let’s cheat! Revolt! Rules were made to be broken!
Hit your plot with the tiller. Ready to plant, right? Wrong. Tilling does a nice job on the topsoil, but the subsoil gets compacted, just like in my Mom’s old garden. Try removing that loose topsoil, with a shovel, and use the tiller again to work your compost into the subsoil, then add your topsoil back on top, and you now have created a way to hold moisture in the subsoil and make it accessible to the roots, making room for bigger carrots and potatoes underground, and healthier peppers and tomatoes above. Try your own variations on double digging, and let us know how it works. Experimenting is one of the joys of gardening.
See, man? We can all live together harmoniously in the garden, man! Peace, brothers and sisters, and say hi to Uncle Starhawk for me.