Sunday, 16 October 2016

Oct 16th Working Bee workshop: How to build a Hugelkultur bed.

Sunday 16 October 2016.
Our working bee workshop was about 'Hugelkulter'.

 Ellen Schindler, our fabulous tutor and guide.

 is an old European gardening technique of creating raised beds - up to 1.5 metres high. They are created by using large pieces of wood in the form of stumps and logs (carbon source). To this are added greens (nitrogen source), well-rotted compost, seaweed, well-rotted manure and so on. The advantages of this technique are; that it utilises large logs that provide a source of slowly available carbon, the wood also absorbs and releases moisture thereby creating a passive irrigation system and the pile itself creates micro-climates by creating shade. For example, it is possible to grow Coriander on the Southern side in Summer (to prevent bolting) and on the Northern side in Winter (to maximise sun exposure).  

How to...
First up, clear the area of weeds and assemble the ingredients.

 Raking and bagging Tradescantia.

Bagging the Tapa tree roots that were on our site - they become invasive in the NZ environment and it's important to remove all of the roots.

Once all the weeds are bagged up, they're ready to be left to rot down into safe and usable organic matter over the next few months.

Removing a stump with the grubber.

 Choose the position and size of the Hugelkultur (ours is 3.5 x 2 m approx.) and outline it with sticks poked into the ground. Then dig a trench approximately 30 cm deep inside of the sticks. The dug out soil will be used as the final layer of the Hugelkultur.

We had already stockpiled our materials icluding large tree logs...

piles of branches...

 And smaller branches and twigs for the final layers of the Hugelkultur.

Bev hand-sawing off a branch. The pieces of wood are easier to handle if they are straight-ish and they don't have protrusions.

 All hands readying the site and the materials.

The Hugelkultur is outlined, dug...

Green material (for Nitrogen) is gathered. 
Fresh grass to push into the gaps between the logs to help the decomposition and to hold the stack together is collected.

 The soil from the trench is piled up outside the sticks and will be used as one of the final layers of the Hugelkultur.

The first layer of big logs and thick stumps go in first and they will provide a source of slowly rotting carbon. The decaying wood absorbs and then releases moisture thereby creating a passive irrigation system. It works well in both free-draining and clay soils. Ensure the logs are not regenerating!

Build them into a closely laid pile of logs and branches.

The grass is used as 'filler' and is put into all the gaps as the pile is formed. This adds nitrogen to the Hugelkultur that balances the carbon contained in the logs and branches. It also helps to keep the pile stable.

Gradually build up layers from big to smaller branches.

Add greens between...

A 30cm wide trench area is kept around the inside edge of the pile. 

Banana leaves are added after being cut to size with the machete.

Introduce old and rotting wood as it already has beneficial mycelium breaking it down and this aids the decay in the Hugelkultur.

The layers are sprinkled with well-rotted compost and soil. Well-rotted manure, coffee grounds and seaweed can also be used.

Keep building and filling. Begin to introduce smaller logs and branches on the top and sides (75 - 100mm diametre).

Add worms now, if there are any around from the earlier work, lots of green material and pack it in tightly.

Note the outline of the pile with the sticks as reference.

Large stumps and short logs are used to build up the foundation layer on the corners.

Below shows a stick, pushed it to act as a stake or peg, to hold the logs and branches in position.

And just in case it's too hard to see the stake - here it is being indicated by my fingertips.

Start mounding the Hugelkultur from the base upwards. Smaller branches and logs are stacked on with soil and green layers.

Smaller branches (30-50mm) are added, again with compost and green material. Add vertical sticks again act as pegs to secure the pile and keep the shape. 

Add well-rotted mulch. Coffeee grounds are ideal too.

 Fine sticks and twigs are used to weave layers into the Hugelkultur to prevent the pile from slipping.

Again, sticks are pushed in vertically to act as pegs and the finer twigs and branches are laid around them to form a retaining basket wall.

Adding the fine twigs and branches near the top is fun!

It's important to keep an eye of the shape of the Hugelkultur to ensure it stays symmetrical and even as it is built up. Pay attention to the corners and the edges.

 More greens for nitrogen - fortunately, we had an abundance of green crops that had started going to seed with the warmer weather.

 More well-rotted compost is added.

The Hugelkultur was smelling beautiful by this stage, with freshly cut lavender, greens and flowering vegetable plants!

Build 2 levels of 'terraces' out of twigs and pegs to help stabilise the soil on the sides of the Hugelkultur. These create growing levels. Use bigger pieces for the pegs and weave through the finer branches and twigs.

The (30cm wide) trench is filled with middle sized branches to create a sturdy edge area to access the Hugelkultur for weeding and so on. See how the original sticks that pegged out our shape are still there as reference.

A layer of mulch is put over this trench area once it's filled with middle sized branches. Use mulch for this and save the soil for the top of the Hugelkultur.

A top layer of soil (about 10cm deep) is added to the top and sides.

Add mulch and/or banana leaves around the edges to protect the Hugelkultur from erosion. Pea or wheat straw can also be used for the top protection layer.

Bev cuts and lays on the final layer of banana leaves to protect our Hugelkultur from erosion and to prevent it from drying out.

Hooray! After a solid 3 hours of teamwork, the Hugelkultur was complete. Usually, this would take 1-2 people the better part of a week!

We thought we would like to give our Hugelkultur a name and decided to call her the 
Helen Kelly Memorial Hugelkultur
(Helen for short)

Once settled, Helen will be ready to plant with seedlings in a week or so.

1 comment:

  1. Thank you for this
    post. Just what I needed to know!