How to Build a Hugelkultur Bed

Explore step-by-step instructions on how to assemble a hugelkultur raised bed.

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Photo By: Image courtesy of LewisCountyRecycles.org

Finished Hugelkultur Bed

Hugelkultur (that’s German for “hill culture”) is a method of building raised beds that takes advantage of natural decomposition processes to create a healthy root environment for plants. Master Recycler Composter volunteers in Chehalis, Washington, built this hugelkultur bed in a day, planting it with ornamentals and edibles. Plants in hugelkultur beds achieve mature size more quickly than in traditional planting beds and need very little watering.

Select a Spot

Before hugelkultur bed construction, this proposed garden area offered a healthy crop of overgrown weeds and unkempt lawn. The black trash bags contain green weeds and grass clippings collected by volunteers to use in the bed construction. If you plan to build a hugelkultur bed, save plant wastes to create layers in the bed.

Add a Base Layer of Wood

Start the bed by clearing vegetation from the proposed site. Remove sod, saving it to add to the bed. Some hugelkultur beds start below soil level, placing base layers in a trench. This method reduces how high the bed stands above ground level. For this bed, volunteers added the first layer—waste wood—directly on top of cleared soil. Do not use treated or chemically infused lumber in hugelkultur beds.

Heap on Nitrogen Sources

Add large tree branches and trimmings as part of the base wood layers. Top the wood with a layer of fresh or composted manure. The nitrogen in the manure helps replace nitrogen that decomposing wood will remove from soil. Having adequate nitrogen available also speeds up the composting process.

Pile on More Wood

Repeat the layering process, adding a new layer of wood. Large diameter timber gives beds the longest lifespan, from 15 to 30 years depending on climate. It’s a good idea to have a chainsaw available to cut wood to size. Longer pieces give the raised bed greater stability.

Recycle Weeds

Building a hugelkultur bed is similar to adding materials to the compost pile. In both instances, you want to layer in brown and green materials. The green weeds removed from the bed site provide a terrific source of nitrogen for the bed. Avoid adding plants that spread by rooting stems or root pieces, such as creeping Charlie or mints, or you risk seeding your bed with a crop of weeds.

Add a Soil Layer

Use a rake to spread a layer of compost or fresh or composted manure on top of other layers. You don’t need thick layers, but it’s a good idea to apply slight pressure as you spread compost so that it fills in some holes between other materials. If the topsoil you removed before creating the bed is poor, add it into the bed layers.

Weeds and Grass Clippings

Continue to layer materials in the bed. Grass clippings and weeds are a great combination to use when building a hugelkultur bed. If you’re creating the bed in fall, you could also layer in autumn leaves. Just be sure to chop them with a mower or leaf vac first, because smaller pieces decompose more quickly.

Rocks Form a Border

This hugelkultur bed features a border of rocks in several spots to add ornamental value. Although the rocks may act as a retaining wall of sorts for the materials in the bed, it’s not necessary to create a support wall for a hugelkultur bed. The materials bind together as they decompose, and plant roots ultimately help maintain the structure. This hugelkultur project is a demonstration bed, so the end remains open to reveal the bed’s layering structure.

Water the Layers

Water the layers as you add them, thoroughly soaking materials. Irrigation helps materials to settle, and it’s also necessary to jump-start the decomposition process. Volunteers cleared all vegetation from this garden site. Weed cloth around the bed keeps exposed soil from becoming muddy during construction.

Grab Some Brush

Continue layering materials until the bed is the height you want. A hugelkultur bed is a great place to dispose of accumulated brush. Instead of burning it or bundling it for curbside yard waste pick-up, you can add it to a hugelkultur bed. Save smaller woody materials for the top layers of the bed.

Keep the Water Coming

Continue to soak the bed until you think it’s wet enough—and then water some more. Use a hose nozzle that allows you to clamp the handle into the “on” position to avoid hand strain. Notice how woody materials in this bed are grouped by size. Place largest diameter materials deep within the bed and smaller sticks toward the top.

Add Soil

As you get the bed to the height you want, it’s time to add soil. Use soil you excavated from the site, if it has a reasonable quality. You might need to blend in some additional quality top soil, depending on what your native soil is like. You’ll plant directly into this layer, so add at least a few inches and even up to a foot.

A Raw Hugelkultur Bed

This bed is finished and ready for planting. The bed may appear tall, but materials will settle as they start to decompose. Build a hugelkultur bed from 10 to 25 percent higher than you desire to account for settling. Build up to 50 percent higher if you fill the bed with large amounts of airy material, like brush.

Finished Hugelkultur Bed Year 1

It’s important to plant your hugelkultur bed immediately after constructing it to keep soil from washing away. After planting, cover exposed soil with mulch. This demonstration bed shows the layered materials on one end.

Finished Hugelkultur Bed Year 2

At the two-year mark, you can see that the woody materials on the exposed end of the bed haven’t changed much, if at all. On average, a hugelkultur bed takes about 15 years to break down completely.