Hügelkultur -
German Origin - Pronunciation - (Hoo-gal-culture) "Hill/Mound Culture"
Standard procedure for the mounding of wood is that larger diameter segments of trees should be put at the bottom and get smaller as you build up, eventually ending in light brush/branches. The textbook height af a hugelkulture around 6-7ft tall, although almost any size/height/width will be more fertile than the area around the mound.
Preferable woods:
- Poplar
- Birch
- Apple
- Alder
- Maple
- Oak
Don't use:
- Cherry (toxins/allelopathic)
- Black locust (long decomposition)
- Black walnut (juglone toxin/allelopathic)
- Cedar (anti-fungal)
- Pine (tannins/sap)
This method of long term gardening is great for building up a large portion of fertile soil if your local soil or land is comprised of poor quality soil, too high of alkilinity or low of alkaline soils. Over time (3-5years) the soil is made to better retain water, store nutrients and aerate itself as the mound slowly sinks and decomposes. This method also bring in myriad soil organisms which can transform the immediate vicinity and perhaps help with poor soils around the hugelkultur.
It's said that a decent sized mound (6-7ft) will be fertile for up to two decades, besides being an incredibly laid back style of gardening (apart from the initial building) it is also a way to help save the earth! Burying logs and dead tree debris help sequester carbon into the earth and keep it stored without releasing it into the air as burnt and unburried wood will.
During the first few years the mound will increase the duration (slightly) of your growing season by effectively composting itself and warm up through the process of decomposition. After the first year water will be well retained though the rotted wood which will act as a sponge, along with any mycelium whcih will take hold in the wood as well. One consideration is that the freasher the wood the longer it will take to leach stored nitrogen, older more rotten wood will already be shedding its nitrogen as the C:N (carbon to nitrogen ratio) will be higher. Therefore if one was to hope to see quick returns in nitrogen, one mmight mix fresh and will rotted wood together, or put more rot wood on top to leach the nitrogen the fresh cut will hope to find and in return expidite the process.
For the first year or so consider legumes and other nitrogen fixers/cover crop to fold into the hugelkulture and help boost the nitrogen content. I would stray away from root crops just incase the logs inhibit directional growth (unless you have large layer of topsoil before wood). After the first year most everything is okay to grow!
Benefits:
- Carbon Sequestration.
- Less/No till.
- (Slightly) longer growing seasons.
- Less watering than traditional beds (given no droughts and after the first year).
- If you choose a purely above ground mound it will bea easier on your back.
- Perhaps fewer weeds given the elevation of mound.
- No need to fertilize.
- More food in less space because of increased surface area of mound.
- Retention of water.
- Great for perennials.
- Increase soil organism concentration in/around hugelkultur.
- Can add on/in later.
- Long term food solution in places which have little water or in general poor soils.
Happy Hugel-ing!
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