Gardening with proper soil depth is more critical for raised garden beds than for trenches. For a raised bed garden to grow well, the soil needs to be loose so plants can easily absorb water and oxygen from the ground. How deep should raised garden beds be? That is the ultimate question. Keep on reading to find out.
Raised Garden beds can be as simple as a few inches above ground level and had you follow the suitable methods. They can allow you to produce incredible yields of delicious vegetables. The soil needs light and air, and the deeper you go, the more it is to maintain its quality. This article answers the question of how deep should a raised garden be and why.
Table Of Contents
How Deep Should Raised Garden Beds Be?
CherryPicks recommend at least 12 inches that suit 90% of cases. A raised garden bed is a good way to grow plants in an urban environment. It is also easy to maintain, as you can use it for all year-round gardening.
A raised garden bed should have at least 8 inches of soil depth to accommodate the root systems of plants because the majority of plant roots are found near the surface. Because most plant roots require 6-8 inches of soil for healthy root growth. A depth of 8-12 inches will suffice for most gardening situations.
- Artichokes - roots require 4 - 5 inches of soil
- Tomatoes - roots require 2 – 8 inches of soil
- Arugula - roots require 8- 10 inches of soil
- Lettuce - roots require 6- 12 inches of soil
- Peas - roots require 2 - 7 inches of soil
- Turnips - roots require 6 - 12 inches of soil
- Cabbage - roots require 12 - 18 inches of soil
- Leeks - roots require 12 – 24 inches of soil
- Garlic - roots require 12 – 24 inches of soil
- Onions - roots require 8 – 24 inches of soil
- Corn - roots require 4 – 8 inches of soil
- Beans (pole) - roots require 8 – 12 inches of soil
- Parsnips - roots require 6 – 18 inches of soil
- Watermelon - roots require 12 – 36 inches of soil
- Parsnips - roots require 6 – 18 inches of soil
- Potatoes - roots require 12 – 30 inches of soil
- Watermelon - roots require 12 – 36 inches of soil
Categories of Depths for Raised Beds
The size of your raised bed depends on your available space and your gardening style. Categories of depths for raised beds
6-inch
6-inch raised beds are the least expensive and can be made by you quickly. You can also use them for more minor seasonal crops such as radishes, carrots or other root crops. They are not very deep, so you will want to place a thick layer of compost or other organic material on the bottom of the bed to ensure good drainage.
12-inch
12-inch raised beds are great for growing many plants, including tomatoes and peppers. They are more profound than 6-inch raised beds, making them more suitable for larger plants such as most bush beans, pole beans, cucumbers and melons.
18-inch
18-inch raised beds are perfect for growing cabbage, broccoli, cauliflower and other root crops. They can be built quickly with minimal tools since you only need a shovel and wheelbarrow to fill the bed with soil.
2-foot
2-foot raised beds are great for growing just about anything. Still, they do require more work than standard garden beds since they have a much deeper depth making it challenging to add organic material directly into the bed without having some soil spill over onto the edges of your garden space.
Benefits of High Raised Beds
Raised garden beds are the most common type of garden bed; you can build them from various materials. Benefits of High-Rise Beds:
- Higher beds allow more plants to be grown in a given space, with greater yields per square foot.
- Raised beds reduce water runoff, reducing erosion from rain or snow melt.
- It's easier to work on raised beds because bending over to reach the soil is not necessary.
- Raised beds are better suited to planting edibles such as tomatoes and potatoes than traditional vegetable gardens because they're more productive and easier to access.
- More usable yard space - Raised beds can be built out of any size you want, giving you extra space to grow plants and vegetables.
Risks of Shallow Garden Beds
Some risks come with building shallow gardens. If you do not take these precautions, you may be shortchanging your vegetable garden by having it sit on top of the soil rather than below it.
- The shallow depth also makes it difficult to irrigate correctly and weed and feed.
- It's also less stable than deeper beds and may not last as long. Shallow beds will not be as firm as those dug out deeper, so they are more likely to collapse.
- You will have to water more often.
- The soil will dry out faster.
- The plants will be prone to diseases and pests.
Factors That Affect the Depth of Raised Beds
Several factors can affect the depth of a raised garden bed. These include:
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Location
The location of the raised garden will determine its depth. If you have a large area to cover, it is best to go for a deeper bed. If you have limited space and only want to grow vegetables, you may only be able to achieve a shallow bed.
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Ergonomic and Adaptive Gardening
Some gardens are designed with specific elements, such as accessibility or aesthetics. The depth of your garden bed should be consistent with these requirements to provide an enjoyable experience for everyone who visits. It includes those with mobility issues who may need to access their crops easily.
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Required Soil for Plants
Most plants require at least 3 inches (7 cm) between their roots and surrounding soil. Planting too shallowly can lead to root rot while planting too deeply can make it difficult for roots to spread out to the edges of your garden bed. If you are growing vegetables, you can determine the required depth by the plants and the climate where they are being grown.
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Drainage
The needed depth will also depend on how deep your soil is already and any drainage problems caused by previous planting or construction work on your plot of land.Consider how much water your plants need when deciding on a proper depth.
Conclusion
The more profound the bed, the more room for root growth and hence a healthier, sturdier plant. Keep them too deep, however, as they shouldn't be so deep that they're hard to get your hands in. As with most things, there are advantages and disadvantages to every aspect of raised garden beds—but generally, you shouldn't go too shallow or too deep from the standard 3 feet.