A Guide to Raised Bed Gardening

Installing, Tending, and Reaping the Benefits of Raised Garden Beds

There’s nothing quite like harvesting your own fresh produce or displaying a bouquet of fragrant flowers you have grown yourself. Whether you’re an experienced gardener or a beginner, installing a raised garden bed is an excellent way to enhance your green thumb. If you are already an enthusiast, this will be a good review. For those looking to begin—we’re here to explain the benefits and challenges of raised bed gardening, offering a step-by-step process for installing your own raised garden bed.

What are raised garden beds?

Raised garden beds are box-shaped planters that sit above the ground. There are two types. One is a box-shaped frame without a bottom that is placed in a garden bed. The second type has a solid bottom and sits on four legs to elevate it above the ground. The latter can be placed anywhere in your yard, or even on a porch.

What are the advantages of raised garden beds?

1. Better soil quality: Gardeners can fill raised beds with high-quality soil that is rich in nutrients, which can also be customized for the needs of specific plants. This soil is typically loose and well-draining, providing an optimal growing environment.
   
   
2. Better drainage: Because raised beds are above ground level, they promote better drainage. Excess moisture can easily escape into the ground below, which prevents waterlogging and water-related issues such as root rot.
   
   
3. Warmer soil: The soil in raised beds tends to warm up more quickly in the spring, which allows for earlier planting and an extended growing season, especially in cooler climates.
   
   
4. Less compaction: Because gardeners don’t walk on the soil in raised beds, there is reduced compaction. This permits plant roots to spread more easily, resulting in healthier plants and increased harvests.
   
   
5. Easier maintenance: Because they tend to be smaller and more manageable than traditional garden plots, raised garden beds are easier to weed, water, and maintain. They are friendly to gardeners because they require less bending and stooping, reducing strain on backs and knees.
   
   
6. Pest and weed control: Raised beds can be fitted with covers or mesh wiring to prevent weeds from propagating and to discourage insects, slugs, and snails—as well as some animals. This reduces the need for harmful pesticides and herbicides. As well, an elevated garden bed can deter or prevent some four-legged plant lovers from having dinner in your garden.
   
   
7. Aesthetic appeal: Raised beds help define and organize garden spaces, offering a cohesive look to your outdoor space. They are available in several materials, including wood (AVO specializes in cedar), stone, or metal, and can add visual interest to a garden.
   
   
8. Keep in mind: You’ll want to consider the costs of your materials and the soil, along with—of course—the seeds and plants you choose. As we discuss further down, root depth is a variable that will influence the height of your sides. Watering requirements might be different than ground planting, as a garden bed is a “closed” system, to a degree. This can also make them more susceptible to heat fluctuations, so monitoring the temperature and sunlight factors will help you succeed with the viability of your plants.     

What is the standard height of a raised garden bed?

Because wood, specifically cedar, is so commonly used for raised garden beds—and it is a material we are very familiar with—we are exploring cedar as the prime example in this article. The gardening information here regarding root and soil depth is appropriate regardless of the material you choose for your sides.  

The standard height of a wood-raised garden bed can vary depending on several factors, including the gardener’s preference, the types of plants being grown, and accessibility needs. However, there are common heights that many gardeners find suitable for different purposes.

Typical heights for wooden raised garden beds are as follows.

1. Standard height: A common standard height for a wood-raised garden bed is around 12 to 18 inches (30 to 45 cm). This height allows for good root depth for most vegetables, flowers, and herbs. It also provides ample soil depth for proper drainage and root growth.
   
   
2. Taller beds (24 to 36 inches): Some gardeners prefer taller beds, ranging from 24 to 36 inches (60 to 90 cm). Taller beds can be beneficial for individuals with mobility issues as they reduce the need for bending or kneeling. They also offer more soil depth, which can be advantageous for certain plants with deep root systems.
   
   Plants with root structures deeper than 24 inches are relatively rare in traditional garden settings. Most garden vegetables and flowers do not require soil depths greater than 24 inches for healthy growth. However, there are a few exceptions, including some trees, shrubs, and perennial plants. Plants you might propagate in a raised garden with root structures that are generally 24 inches or longer may include lilac shrubs, as well as asparagus, horseradish, dandelion (people enjoy this medicinally or for tea). For flowers and perennials, black-eyed Susan, Russian sage, and yarrow have a root structure that can reach deep into the soil.
   
   It is important to note that even for plants with deep root systems, the majority of their root mass is often concentrated in the top few feet of soil, where water, oxygen, and nutrients are more readily available. The deeper roots primarily serve to anchor the plant and seek out supplemental water during dry periods.
   
   
3. Deep root crops (18 to 24 inches): If you plan to grow deep-rooted crops, a bed height of 18 to 24 inches (45 to 60 cm) may be beneficial. This allows these crops to develop properly without encountering obstacles. Several plants commonly grown in raised garden beds have deep root structures, requiring ample soil depth for proper growth and development.
   
   Deep-rooted crops include carrots, parsnips, potatoes, beets, rutabagas, turnips, artichokes, sunchokes, fennel, and radishes (some varieties, especially daikon, have deep root structures).
   
   When planning a raised garden bed for plants with deep root systems, consider the specific requirements of each plant. As with all plantings, providing adequate soil depth, good drainage, and loose, fertile soil will help these plants thrive and produce healthy, flavorful harvests.
   
   
4. Herb or flower beds (6 to 12 inches): For herb gardens or flower beds, a lower height of 6 to 12 inches (15 to 30 cm) may be sufficient. Herbs and many flowers have shallower root systems, so they do not require as much soil depth. Several common vegetables have root structures that typically range from 6 to 12 inches deep. These plants thrive in garden beds with adequate soil depth and good drainage.
   
   These vegetables are some of the ones commonly planted with great harvest success in raised gardens: tomatoes, peppers, cucumbers, squash, lettuce, spinach, red radishes, onions, garlic, kale, and chard. Carrots, turnips, and beets can do well in 12 inches of soils—just keep an eye on them. Common fruits include strawberries, raspberries, blackberries, blueberries, huckleberries, and grapevines and kiwi vines. Shrubs and bushes include elderberries and currants.
   
   In general, the plants above are well-suited for garden beds with soil depths of 6 to 12 inches, allowing their root systems to establish and access nutrients and water effectively.
   
   
5. Custom heights: As we see above, the height of your raised garden bed should be based on your specific needs and the plants you intend to grow. Some gardeners create custom heights based on their gardening style, space availability, and aesthetic preferences. When deciding on the height of your wood-raised garden bed, keep these factors in mind:

Accessibility: Ensure the height is comfortable for planting, tending, and harvesting without straining your back.

Planting needs: Some plants have specific root depth requirements, so tailor the height to accommodate their needs.

Soil depth: Adequate soil depth is crucial for healthy plant growth, so choose a height that provides ample space for roots to grow and access nutrients.

Ultimately, the best height for your raised garden bed will depend on your specific circumstances and gardening goals. It’s often helpful to start with a standard height and adjust based on your experience and plant requirements over time.

Why use cedar for my raised garden beds?

1. Natural resistance to rot: Cedar is naturally resistant to rot, decay, and insect damage due to its natural oils and compounds. This makes cedar a long-lasting option for raised beds, often lasting 10 years or more without the need for chemical treatments.

2. Durability: Cedar is a strong and sturdy wood, able to withstand the elements without warping or splitting. This durability ensures that cedar raised beds maintain their structural integrity over time.

3. Aesthetic appeal: Cedar has a beautiful, natural appearance with warm tones that blend well with garden surroundings. It adds a touch of elegance and charm to the garden, enhancing its visual appeal.

4. Lightweight and easy to work with: Cedar is relatively lightweight compared to stone, making it easier to transport and work with during installation. This is especially beneficial for DIY gardeners.

5. Natural resistance to moisture: Cedar’s natural oils make it resistant to moisture, helping to prevent the wood from rotting in damp conditions. This is ideal for raised beds where soil moisture levels can vary.

6. Low maintenance: Cedar requires minimal maintenance over its lifespan. Unlike other woods, it doesn’t need to be treated with chemicals or preservatives, making it an environmentally friendly option.

7. Good insulation for roots: Cedar provides insulation for plant roots, helping to regulate soil temperature. This can be beneficial for plants sensitive to temperature fluctuations.

How do I install a raised garden bed that sits above the ground?

1. Choose the right location: Select a spot that receives plenty of sunlight throughout the day, as most plants require at least six to eight hours of sunlight to thrive. Make sure the underlying area has good drainage.

2. Gather your materials:

• Cedar, bricks, or stones for the sides of the raised bed
• Screws or nails (if using cedar)
• Weed barrier fabric
• Soil and compost
• Shovel
• Level
• Tape measure

3. Build the frame: If you’re using cedar, assemble the sides of the raised bed by screwing or nailing them together to form a rectangular or square frame. Make sure the corners are square and the sides are sturdy enough to hold the soil. If you’re using bricks or stones, arrange them in the desired shape, making sure the edges are level.

4. Prepare the ground: Before you place the frame or stones in position, prepare the ground underneath. Use a shovel to remove any grass, weeds, or debris from the area, and then use a rake to level the ground as much as possible.

5. Place the frame: Once the ground is prepared, place the cedar frame or stones in position. Use a level to ensure that the sides are straight and level. If you’re using multiple rows of bricks or stones, make sure they’re stacked evenly and securely. 

6. Add the weed barrier: Place a layer of weed barrier fabric inside the frame or between the stones. Cut the fabric to size and secure it in place with stakes or by tucking it under the edges of the frame.

7. Fill with soil and compost: Mix equal parts of soil and compost to create a nutrient-rich growing medium for your plants. Use a shovel to fill the bed, making sure to distribute the soil evenly and avoid compacting it too much.
   
   
8. Plant your garden: Choose the fruits, vegetables, and flowers that are suited to your climate and the amount of sunlight your garden receives. Space your plants according to their specific requirements, and water them thoroughly after planting

9. Maintain your garden: To ensure a successful harvest, water your garden regularly, add mulch to retain moisture and suppress weeds, and fertilize as needed. Watch for pests and diseases and address any issues promptly.

Raised Bed Recap

Installing a raised garden bed is a rewarding and relatively simple project that can enhance your outdoor space. While there are challenges to consider, for most gardeners, these are far outweighed by the satisfaction of growing their own supply of fresh vegetables, fruits, and flowers. By following these instructions and dedicating a little time and effort to your garden, you’ll be well on your way to starting your morning with sweet strawberries, enjoying a freshly harvested salad made from your own lettuce and tomatoes, or admiring the vibrant blooms of favorite flowers in no time!

AVO Fence & Supply offers multiple sizes and styles of cedar raised garden beds. Choose from 4x8, 4x4, or any size you prefer. We can also add legs and post caps! Whichever size or style you choose, these quality garden beds provide an attractive and functional addition to your outdoor space.

AVO Fence & Supply is a provider of high-quality fencing products and supplies with locations in Stoughton, Plymouth, and Hingham, MA. We are also the leading supplier of cedar to homeowners and contractors in the New England area. Give us a call today at (781) 341-2963.