Hukelkulter garden beds
I’ve been in full swing making new garden beds. I’ve used bricks for alot of them and even made a wall with bricks that doubled as a bed. I read about hukelkulter where logs are used as the foundation for a bed with soil on top. (Roughly translated it means mound culture in German). As the logs break down over the years they generate heat and nutrients and also water they’ve absorbed. Apparently the bed won’t need watering after it’s first year of getting established. We have heavy clay soil so I was planning on digging down and building up the bed anyway so decided to give it a try. If you’re wanting a quick way to make a new bed this isn’t necessarily your best option but once done shouldn’t require much maintenance.
How to make a hukelkulter garden bed
I dug three pits for my beds – roughly 1m wide by 2m long with enough space in between each to get a wheel barrow through. The length didn’t matter as much – make it to fit your space but don’t make it too wide or you won’t be able to reach into the middle easily. The depth was just a spade deep as that was easiest to dig up. Fortunately I didn’t fill them straight away after I dug them as it rained and showed me that they filled up with water and being clay soil didn’t drain very well (this would not be ideal having plant roots sitting in that all winter). I redug the bottom of each so it sloped away into a channel I dug which lead out into the paddock. Because we had some spare from another drainage project I used a piece of novocoil and covered it with rock. You could just fill the channel with something like old bricks or rocks for drainage rather than using coil. Unfortunately I didn’t take photos at this point.
We have very poor drainage so I took a couple of days in the wet watching to see that the water was draining away – it didn’t need to be perfect but I didn’t want big pools of water forming. If you have good drainage then lucky you – don’t worry about this step!
The logs I used to fill the pits were macrocarpa as we had a tree come down a year ago. I used as many large rounds as I could manage to lift plus various smaller branches and twigs to roughly cover the base of the pit. Then I filled it up with sheep manure, grass clippings, straw, kitchen scraps and so on – just what I had available. I put back some of the nicer looking soil I had dug out then covered each with two wheel barrow loads of bought garden mix soil. (I’ve bought trailer loads of soil to add to the garden as it will take years of adding compost, seaweed etc to get our clay soil performing well.) Because I wasn’t planting them out straight away I covered them with plastic to protect that nice new soil.
The beds have now all been planted and I’ve had mixed success. The middle bed I planted with early potatoes in late September which, a month later, have grown really well. (Initially I used some old concrete mesh to protect the beds from a wayward puppy but I could take these out now and reuse them somewhere else).
At the same time I planted the far bed with dwarf beans. I had straw on as mulch around them initially but the wind kept blowing it away and I’ve since added some mulched leaves. It was probably a bit early to plant them and it wasn’t until I covered the bed with a couple of upturned tubs that the seeds germinated. Then I had a problem with slugs in this bed which ate my tender stalks and have only had a 50% survival rate so I’ll need to plant some more.
The final bed I’ve only just planted with climbing beans. I’m happy with my bamboo climbing structure but have yet to see if it will be hold up to wind and beans!
I didn’t make my beds too high but examples I’ve seen have them very wide and high and filled with heaps more material than I did which would last longer. Here is a link with some awesome looking beds – one is so high you’re harvesting veg standing up! I hope mine are as successful.
Summary of making the bed
- Dig a pit –
- Width – 1m means you can easily reach the middle of the bed
- Length – to suit your garden space. Don’t make it too long or you will be tempted to jump over rather than go round the bed
- Depth – at least a spade depth, more if you can
- Fill the bottom with as much hardwood as you can – the bigger the logs the better. Some trees have natural repelling properties eg black walnut and pine so don’t use them.
- Interfill with sticks, green and brown material as if you were composting.
- Top with soil.
Pros and cons?
- Hard to keep the mulch on the sloping sides of the beds until the plants are established.
- More surface area for the birds to have a dig at as the sides are exposed; currently they’re unearthing my bean seeds.
- Rat haven (probably digging in after the veggie scraps and discovering spots to nest under the branches in there).
- Time consuming to make to dig down into the ground and more so if drainage digging is required (although this would be the same for any kind of bed).
- No bed materials to buy or construction required.
- Decomposing logs provide warmth, nutrients and aeration although time will tell if this is happening and providing a benefit or not.
- The decomposing logs also provide water meaning the bed shouldn’t need watering although ditto about time telling if this happens or not.
- A good way to get rid of logs, branches, grass clippings and so on.
Update six weeks on – would I recommend the mounded bed? Not really. Check out my post on my experiments with making garden beds here.