'Lazy Curve' - 4' x 12' Raised Garden Bed (2024)

FAQs

What is the best length for a raised garden bed? ›

The Best Length for a Raised Bed

In my experience, the best length for a bed maxes out around 10 to 12 feet long. I've installed beds as long as 25 feet, but we encountered issues with holding the bed structure together as the soil was added. Wooden beds that are too long might start to bow.

Depending on your budget and gardening goals, you can line the bottom of your raised garden beds with wide-mesh hardware cloth, stainless steel mesh, landscape fabric, burlap sack, or newspaper/cardboard.

Gardening on slopes can lead to soil erosion because the exposed soil and nutrients run down the hill. The key here is to build a level raised bed according to the slope to prevent erosion and enjoy the benefits of raised beds and terraced gardens.

Luckily, there are plenty of perfect candidates. Herbs like basil, cilantro, and other low leafy greens like lettuce will grow and grow with just 6 inches of soil. A 1-foot raised bed is more than enough to accommodate a salad garden box plan. Carrots, radishes and peppers thrive with 12 inches or more.

The Ideal Raised Bed Height for Productivity Is 16 to 18 Inches. If you want to be able to grow everything from a small lettuce plant to a large squash plant in your raised bed, I recommend going with a height between 16 and 18 inches.

Tomatoes, for example, which benefit from being planted deeply, require about 24 to 36 inches (60 to 90 cm) of depth for their roots to grow. However, if your raised bed is about a foot high, the growth of the plant may simply be slightly stunted.

The cons of raised beds

Use rot-resistant wood if you go with boards and figure even those eventually will have to be replaced. The soil mix also can be a significant, albeit one-time, expense. Raised beds need water more often since the soil is more exposed to air and dries quicker.

Beds off the ground and supported by legs are built or manufactured with a bottom. We recommend lining this space with a permeable material (like a weed mat or landscape fabric) to help preserve the structure and prevent soil loss when watering.

If you're planning a 12-inch deep raised bed, you'll need approximately 24 cubic feet of soil to fill a 4x8 bed. A depth of 18 inches will require approximately 36 cubic feet of soil. The type of soil you use will also affect the volume required to fill your raised bed.

What can you grow in an 18-inch-deep garden bed? Eighteen inches is the minimum height needed for plants like tomatoes, cucumbers, squash, zucchini, and kale—plants that have a bigger root base and need more nutrients and space to spread out. This height also allows for better drainage.

What vegetables can grow in 12 inches of soil? ›

While individual preferences will differ, a standard 4'x8′ bed with a depth of 10 inches (constructed using two layers of 2×6 boards) provides excellent versatility for growing a wide range of vegetables.

Deep-rooted vegetables, for instance, would require a deeper bed than shallow-rooted plants. A depth of six to twelve inches is usually sufficient for most plants. If your soil is heavy clay, however, it may be necessary to go deeper. The optimum size for raised garden beds is around four feet wide and eight feet long.

Raised garden beds that are too long can become a nuisance. They also tempt people to take a shortcut and step in the beds to get across. Consider keeping your beds short enough that going around them isn't a chore. Two twelve-foot-long beds are more manageable than one 24-foot bed.