I used to be a proponent of rototilling. It was comparatively easy to hand digging new beds. Especially if you have clay soil.
So as it turns out we ended up having to hand dig the beds later on. After we rototilled it rained for several days and re-compacted the soil. When we dug it was just a shovel head deep and flipped the soil over.
If only I had known how much damage we had done to the soil! Throughout the growing season I noticed that there weren’t any worms! Before we started there were so many of them. Where did they all go?
Then I started researching gardening techniques. We used to use raised beds at our previous home. Unfortunately raised beds would be cost prohibitive for us. I needed to fix our soil!
As it turns out, rototilling creates a hardpan right under the turned soil by compacting it with the blades and then burnishing into a nice hard, shiny surface. This not only creates a barrier keeping worms out of the tilled soil, but it also reduces drainage and keeps roots for penetrating the soil deeply. Rototilling also created a horrendous weed problem for us. Our two worst weeds are Bindweed and Bermuda Grass. Both are perennials which easily propagate themselves through cut roots. Rototilling ended up cutting these roots up into small pieces and distributing them all through the beds. It also brought all the buried, dormant weed seeds up to the surface to germinate. Our weed problem was a neverending battle. A war we just couldn’t win.
Deeper soil means deeper roots which mean closer spacing. When the roots can’t go deep, the are forced to spread out, which causes too much competition between plants, requiring them to be spaced further apart.
The French Intensive Garden uses this rooting concept. Plants are tight together, and yet flourish. So how do you get the soil deep enough? And how deep is deep enough? Easy, Double Digging, which helps create deep, loose soil 2′ deep without destroying soil structure. This is essential to not only worms, but bacteria, fungi, and other beneficial organisms. It also helps keep buried weed seeds from coming to the surface. Double digging also allows me to pull out weed roots as I went along.
You will need a round head shovel, a spading fork, two 5 gallon buckets (or wheel barrow), and a metal rake (not shown). The contractor style D-handle (on the spading fork) is preferred over the full length handle (on the shovel) because it will save your back. However, I don’t have a D-handle shovel. I do need to add a quick note about tools. Buy good quality tools! This is our second spading fork in a month. I ended up returning the first one because we broke the handle. It was a fiberglass handle and the company claimed it was stronger than all other fiberglass handles. I believe it even had a 15 year warranty. But it wasn’t nearly as strong as a wood handle – which is also more expensive. When choosing a wood handled tool definitely look closely at it and make sure there aren’t any knots or other defects in the wood. I was able to find only one without knots out of 5 on the racks and even this one is starting to show stress.
The following day you start digging. First start by making a trench about a shovel head deep and wide and put the dirt into 5 gallon buckets.
Once you have your trench dug, take your spading fork and start loosening up the soil at the bottom of the trench. Continue loosening until you can easily push the spading fork all the way in to the top of the tines all the way across the trench.
Now create a second trench moving the soil into the first trench. Don’t flip the soil, just move it. Loosen the soil at the bottom of the trench has before. Continue these procedures until you’ve gotten to the last trench. Then take your buckets of soil and dump those into the last trench. Rake the bed smooth. Don’t worry about any large dirt clods. If you water with sprinklers, or if it’s raining the clods will break down. Make sure to work backwards so you don’t recompact your now loose soil by standing/stepping on it.
5 thoughts on “Double Digging”
My grandfather double dug everything. I hated doing it, as it was usually done in the rain while the soil was 'moist' but not soggy. It gives me a bit of a nervous tick now 😉 We have mostly raised beds here, but I do still double dig some areas when absolutely necessary, but avoid it when I can. I agree though, rototilling is the absolute worst thing you can do to soil! I did it once in soil that resembled concrete at our last house, but I'd NEVER do it again!
Hmm. We use a cultivator to break up dirt that's never been broken up, and to work in compost, composted chicken litter, and unfortunately it's been necessary to add topsoil and wood-based garden soil a bunch of times. I think that to rototill or not to cultivate is going to depend greatly on whether one's yard has *ever* been cultivated, and what the soil is predominantly composed of. In our case, we could make pottery with it, because of the insane amount of clay. But by the same token, clay is really good because the organic matter you add to it tends to stay there.
And we have scads of worms. The trick with using a cultivator is to not use it during the wet season, and if you must use it during the wet season, give the dirt a few days to dry out, and don't go deeper than 4 inches, otherwise you'll be whipping up worm smoothies in the dirt. Give the guys a chance to retreat deeper, IOW.
My only caveat with this… Don't rototill your plot to be planted until you're fairly certain the wet season is over, because we had freak rain this year in February and March, and even double-dug raised beds will get temporarily compacted by that. It also helps to grow things that encourage mycohrrizae, like fava. It can also be purchased, added sparingly to the watering can, and broadcast during watering. It essentially builds your planted bed into a water- and nutrient-sharing matrix. Grow plants that root deeply near the beds or even in them, too.
Thanks for the article and thanks for your comment Curbstone! I’m double-digging my garden bed after 2 years of utter garden failure using the 6-inch closed-off raised beds of the All New SFG book (if you’re a noob to gardening like I was, take my advice – you CAN’T grow vegetables in 6 inches of soil, no matter how good it is!)
Anyway I’m scrambling to get my bed dug by 3/11, which is my date to start cold-weather crops outside, and I’ve been really worried about getting even close to done because it rained all day and night yesterday and it’s not looking like it’ll be warm enough to dry that out any time soon. I figured I would mess up the soil by digging it wet (it’s probably not the worst but it is definitely a clay soil), but it’s great to know that it has traditionally been done that way for generations! I just might be able to finish in time to plant on schedule! Thanks again for the info.
Mike, don’t get me started on SFG! I tried it in 10″ beds and it still was my worst gardening year ever. The soil mix he touts is one of the worst I’ve ever used to boot.
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