Double digging and Hugelkultur

[coppice]

Both of these goes back to 'french intensive' bed gardening. It has probably aquired a dozen or more names over the years as it gets "re"discovered by home gardeners.

I'll over simplify.

Hugelkultur: for me this has been a desparate attempt at changing a sandy garden to hold onto moisture. I've dug out trenches up to three feet deep and back filled the hole with brush and even unpainted or untreated logs and as much yard waste as I could hustle. As woody stuff breaks down in the first year it doesn't have its full impact as a huge sponge. But over time it does work (like year two). The net effect are quite obvious raised beds. I have likened them as looking like burried volkswagons.

Double digging: when I've resorted to this it has been occasionaly to resolve for my peice of mind what had been burried in the past in my yard. Older new england door yard gardens were often middens. Finding the O'Leary cow settled what has been burried there. Finding Grampa's model-T got me to move the garden...

Most often tho, the problem was clay. I'll start out lazy and let the organic material serve to soften soil, but I dig every couple years to chisel out (some more) compacted clay and work yard waste into that subsoil to improve drainage and give crops roots room to tease apart some more clay. The more yard waste you can add to subsoil the better worms can get in and continue your work for you.

Both Hugelkultur and double digging have been for me, an autumnal task. It lets me hide brassica corn amaranth or sorgum stalks where I don't have to chop them up or hate them as I dig em out of compost pile next spring. They can gently cold compost in the subsoil where nobody will have to say bad words about them as the decompose.

Once a slow to decompose stalk is burried deeper than your spade or fork will disturb, it and your serenity will be conserved. Worms like em too.

[coppice]

Double digging to prep a bed for carrot for me usualy includes sifting it. This works in finished compost, to reduce funny shaped root and lets me cull out gravel. Besides carrot likes soft spongy soil to grow in.

I broadcast seed mixed equally 1 part carrot seed, and 1 part radish. The radish germinates quickly and shades carrot seed. This also give me and any young children thinning oppourtunities with immeadiate gratification.

[Deleted]

I've done a combo of this. My dense clay layer goes down about two feet before turning into loam and deeper sandy loam. I dug down to the damp sandy loam and back filled starting with the largest branches I could pull out of the woods, layering with soil,followed by leaves weeds, smaller branchs, more soil, and finally the top layer got mixed with bulk semifinished woodchip and leaf compost. I mixed the clay in with the other soil as much as possible. The roots can now penetrate down to the moist soil rather. The deep decaying logs, even if they can't decompose into good soil will provide space for root penetration and worm activity.

Granted, bringing the subsoil to the top and burying the top soil (double digging) does not improve the soil in most cases, but if you are trying to turn bad soil into good soil this works.

[redneckplanter]

interesting....how long ya'll figgure the logs will take to break down?
have you experimented with woody material in a windrow cold compost type setting for poor soils?
trying that this year with my small pile....curious on the breakdown rate if it is kept moist all year by the other carbon organics.

[paquebot]

That hugelkultur system is strictly for retaining moisture since the wood is worthless for supplying nutrients. In a ton of dry wood, there are an average 2.2 pounds of nutrients. (You'll get the same from 150 pounds of oak leaves.) In the forest, huge logs lay for years and become a big pile of something which looks like a great soil amendment. The fact that nothing is presently growing in it should go far in determining its nutritional value. So little to start with and then fungi consumed that.

Martin

[redneckplanter]

thanks bot....the moisture retention sure is appealing though in my climate...smiles

[coppice]

First, Paquebot is right; logs don't provide much of anything other than moisture retention. Re-digging double dug beds makes the point of my shovel (and me) beleive its at least year two, if not three before logs get fully punky.

[redneckplanter]

wanted to revisit this thread.lol
plan on incorporating a buncha buried branches this year with my leaf pile.

[coppice]

Red if the woody stuff you're burrying is below how deep you till or fork the garden, the woody bits can just hang out down there and break down in peace.