Read through the pros and cons of each to select a method that works best for you and your space, or mix and match for a hybrid solution that strikes your fancy!
1. Hugel Beds
Brought to popularity by Austrian farmer, Sepp Holzer, hugelkultur is a technique that translates to “mounded beds.” When possible, hugel beds are an ideal way of adding raised garden space to your landscape. Manufactured by creating consecutive layers of decaying logs, sticks, leaves and other biomass that are topped off with soil. They’re fantastic for maintaining moisture, fostering microbiology and providing ongoing fertility as components continue to decay over time. However great as they may be, building these mound-like beds correctly to facilitate effective growing is a bit trickier than the average, inexperienced homeowner might like.
First off, it’s important to source hardwood logs of the right size and at the right stage of decay to start, which can be a bit difficult to find en masse—logs that are too large and fresh to begin will take too long to break down and won’t hold moisture as well. (As a business, we’re exploring ways we can create a supply of suitably decayed logs for this). If you happen to have forested land, however, you may find this to be a non-issue. Secondly, the labor involved in preparing the ground (you’ll want to remove existing grass and vegetation and dig down into your existing soil about 12” to start the first layer), sourcing materials and constructing the mound itself can be a bit too physically and logistically demanding.
That being said, if you’re interested in taking this approach, have the time and are willing to do the work, hugel beds can be the perfect way to create raised growing space for very little cost. They can be built almost entirely with found materials and often require less soil to start. They are an excellent way to accelerate soil building, and the layer of rotting logs acts like a sponge, holding moisture for roots to access. We have seen this drastically reduce the need for irrigation in your veggie garden. You can customize their height to create added convenience or optimize vertical area for growing, and they all but eliminate the need for irrigation by absorbing rainwater and storing moisture for extended release. They’re also quite effective for erosion control.
Pros: reduce the need for irrigation, manage erosion and foster ongoing fertility, can be easy to build affordably or free
Cons: can be hard to source supplies to start, labor-intensive
2. Raised Container Beds
While certainly nothing new, building raised container beds is on trend in recent years—they’re a staple of every cottagecore lover’s dream garden. In addition to their practicality, their neat and clean look appeals to many folks’ desire for a more tidy aesthetic. But constructing an effective boxed raised bed isn’t necessarily a no-brainer. Most commonly they’re built from wood or stone, but other hardscaping materials and metal are used sometimes, too.
To start, we always recommend removing grass or existing vegetation at the foundation of the raised bed and turning the underlying soil to improve permeability, moisture retention and soil integration. Even more ideal would be to build a small hugel bed at the bottom. Building a raised bed directly on top of lawn and compacted soil can create less-than-ideal conditions for growing, which can be exacerbated by the various wood, metal and hardscape materials commonly used to construct the four-sided container box itself. As with any method, there are pros and cons to building a boxed raised bed. The costs of materials for construction and for filling the container with a manufactured growing medium are higher, and increase depending on size and number of containers constructed. However, ease of maintenance and convenience are two of the primary benefits that this type of raised bed offers.
Pros: easy to maintain, keep grass out, customizable height can add convenience for harvesting and management
Cons: can become costly depending on height and materials used to build, require larger initial input of manufactured soil medium, may require irrigation and ongoing fertility management depending on construction materials, raised beds built from wood can wick moisture from the soil, raised beds built from stone or other hardscaping materials can overheat the soil
Additional material-specific considerations:
Similar to identifying what type of raised bed is right for you and your space, there are a number of factors to consider when selecting materials for their construction. Recently, in fact, we’ve been diving even deeper into our company-wide sourcing protocols to ensure that the materials we use align as closely with our values, and those of our clients, as possible. This ongoing research and reflection continues to yield interesting data as well as uncover additional supply chain complexities, including availability, cost and carbon footprint.
When building raised container beds from wood, a multitude of options exist. And with each option comes various considerations that might affect your decision. In an ideal world, one could use locally milled wood from black locust and other rot and insect-resistant species. Unfortunately, though, this kind of lumber, especially in the form of boards, isn’t readily available commercially. So, for a number of reasons, we use pressure-treated pine. It’s accessible, it’s produced and processed widely in our home state of Georgia (which minimizes shipping distance and associated emissions), and it’s durable, ensuring that our clients can enjoy their raised beds for many, many years without needing to replace, repair or rebuild.
Historically, though, the use of pressure-treated wood has raised concerns regarding potential toxicity from chemicals formerly used in its production, particularly Chromated Copper Arsenate (CCA). However, since 2004, the use of CCA was discontinued in residential lumber applications. Supply stores like Lowe’s and Home Depot voluntarily replaced the lumber in their supply chain with CCA-free wood, opting for treatment with the preservative Alkaline Copper Quaternary (ACQ) instead. While CCA and most other highly concerning hazardous chemicals are no longer found in lumber for residential use, pressure-treated wood does indeed contain chemicals. And the emissions used in processing methods that avoid CCA have ramifications of their own. For businesses and consumers alike, it’s important to evaluate these pros and cons with consideration to both the health and safety of our communities and the planet and to make educated, values-aligned decisions. If you’re interested in learning more, I found this Iowa State University article on toxicity concerns with raised beds to be informative: https://www.extension.iastate.edu/smallfarms/toxicity-concerns-about-raised-bed-construction-materials.
Alternatively, whether for aesthetics or out of an abundance of caution, we have constructed raised beds from cedar for clients upon request. While a wonderful, durable choice for many outdoor applications, unfortunately cedar has a limited life in our humid climate when in continuous contact with the ground and/or soil. This, combined with its economic and environmental costs—most commercially available cedar is western redcedar, logged and milled out west then shipped thousands of miles to reach us here—make it a less attractive choice.
Ultimately, lumber is the most cost-effective and readily available choice for raised container bed construction, but can potentially wick moisture from the soil and increase the need for irrigation.
3. In-ground beds
Convenient to create, in-ground beds are an excellent choice for flat or minimally sloped property. You can convert an existing lawn into a vegetable garden in a variety of ways. To start, it’s important to eliminate grass and weeds throughout your growing area. You can do so through solarization or occultation. Solarization involves covering the ground with transparent plastic for numerous weeks to harness the heat of the sun to kill grass, weeds, seeds and even bacteria and fungus. Occultation employs opaque (usually black) tarp or plastic to prevent light penetration and subsequently kill grass and weeds. Additionally, while we recommend that you minimize tilling to avoid disrupting soil structure, it can be a quick and efficient way of starting an in-ground garden, especially if you’re setting up a long-term system designed to function without ongoing tilling. Using no-till methods moving forward will ensure increased soil health and fertility. You can also eliminate grass and start a garden in your yard by sheet mulching heavily and building beds from compost and other mediums on top. Ultimately, in-ground beds are easy and affordable to build, but require more ongoing management. I wrote another blog post all about sheet mulching, which you can check out here.
Pros: easy to build, reduced need for irrigation
Cons: can be more management intensive and more easily succumb to weeds
4. Planting bed ‘pocket gardens’
Particularly useful for landscapes with little sun, integrating small ‘pocket gardens’ into existing planting beds throughout your landscape can be the perfect way to augment food production at home and maximize space. Introducing annual vegetables and edible flowers into your planting beds is also a fantastic way to add seasonal color to your garden. The existing fertility and plant communities within your beds create an ideal growing environment for veggies, and may also minimize the need for irrigation. While planting bed pocket gardening works well for some, and under specific site conditions, this decentralized approach can be inconvenient for maintenance and harvesting and more difficult to protect from predators.
Pros: optimize pockets of light in shady landscapes, add seasonal color and variety to planting beds, easy to implement
Cons: scattered distribution can be more difficult for harvesting and managing, may be more susceptible to predation from your local critters, and requires more nuanced plant ID skills
5. Terrace beds
Terraces can be an excellent way to mitigate erosion while creating raised spaces for growing in the landscape, particularly on more severely sloped land. Because they are most commonly built into an existing slope, their construction usually entails building just three sides to create a stable, contained space. That, combined with the ability to backfill with earth from the slope itself, can lower construction overall costs. However, terraces can sometimes limit access and mobility compared to other types of raised beds. Ultimately, the degree of slope, desired use of space and functionality will help determine whether or not terraces are right for you and your landscape.
Pros: excellent way to control erosion and create arable space on sloped property
Cons: can potentially limit mobility
Get to growing!
Adding an annual vegetable garden to your landscape is both fun and functional. You’ll not only reap the rewards of growing fresh, nutrient-rich food at home, but you’ll benefit pollinators and bolster the overall health of your garden by increasing plant diversity throughout your space as well.