Growing your own organic vegetables and herbs is great for your health, your taste buds, and the environment. You may be even better served if you do so in organic raised beds.
Using raised garden beds offers many advantages over traditional ground-based garden beds. Note that raised beds differ from planter boxes!
- Planter boxes have solid sides and a bottom. They are self-contained and are only good for plants with shallow roots.
- Raised beds sit on top of the soil. They have raised sides but no base. This allows deeply-rooting plants to grow beyond the depth of the raised bed.
Why Use Raised Beds?
First and foremost, raised garden beds are much more back-friendly, from preparing the soil to maintaining your plants and harvesting your vegetables and herbs. These beds also hold their soil in place, their water in place, and produce remarkably large harvests for their size. In fact, many experienced gardeners find that the yield from a raised bed far exceeds that from a traditional garden bed.
Additionally, if you ever move, your raised beds may be able to be transported with you.
What Are Raised Beds Made Of?
Raised garden beds can be made from various materials: wood, galvanized steel, Color Bond steel, poly. You can also build your own beds from wood, bricks, old pallets, wooden sleepers, rock, stone – you’re only limited by your imagination and willingness to do it yourself! Wood beds will last for a shorter time than steel beds will, however, they should still last between 10-15 years before they need to be replaced.
For an organic garden and for longevity, use untreated hardwood in preference to treated pine. Try not to use treated lumber as this contains creosote which will leech into the soil. Also avoid using concrete.
How to Make an Organic Raised Garden Bed
Plan Your Garden Beds in Advance
- Locate them in a level spot with full sun, away from shade trees and bushes. For vegetables, your beds will need at least 8 hours of full sun per day. Leafy crops like lettuce, however, need some shade or dappled sunlight.
Prevent Weed Growth
- Cut grass and weeds under the site of the raised beds as short as possible. Line the base of the raised bed with cardboard sheets or newspapers overlapped prior to filling it with soil.
- Your beds can be as large or small as you’d like, but ideally will be limited to 6-8 feet (2-2.5 meters) in length so that you can easily access all parts of the plot. Most beds are 4 feet (1.3 meters) wide as this is a reachable width. If you are building multiple beds, leave room between them to walk a wheelbarrow.
How Deep Should a Raised Bed Garden Be?
- This depends on what you wish to grow! For root vegetables, your beds need to be at least 1-1.5 feet in depth (45cm). The deeper your bed, however, the better it will be for your vegetables and your back! Slightly below waist level is an ideal depth for the yield of crops and comfort while gardening. (Also – consider a bed of at least a meter tall to discourage surprise visitors like snakes if you are anywhere near bush land, a creek, a pond, or a reserve.)
- Plants with very deep roots (up to 1 meter) include tomatoes, pumpkin, sweet potato, and asparagus. Plants with shallow roots (30-45cm long) include broccoli, cabbage, potato, onion, bok choy, spinach, and lettuce.
Do I Need to Line a Raised Garden Bed?
- If your bed material is treated pine or otherwise likely to leech from the bed, line the inside of the sides with builders’ plastic.
What Soil Should I Fill my Raised Bed With?
- Ideally, and to save money, purchase soil in bulk from a landscaping center. You only need about 30-40cm of premium topsoil for your garden to thrive.
- Many organic gardeners find that filing the bottom half of the raised bed with organic garden waste will do the trick. Use grass clippings, leaves, lower-quality fill soil, crushed granite, sticks, etc.
- The organic matter provides a healthy living environment for fungus, worms, microbes, and other critters that make your organic garden healthier. You could also add compost from your own compost pile.
- In time, this organic matter breaks down into rich soil.
Consider What you Wish to Plant
- You need to plan ahead for your chosen crops’ mature height and spread. Pumpkins, corn, melons, etc need plenty of space.
Do Raised Beds Dry Out Quickly?
While it’s true that plants in pots do dry quickly and can overheat, a raised bed behaves in the same way as an in-ground garden in terms of soil heating and moisture. Additionally, when you water a raised bed, the water remains right there – in the bed. Ground-based gardens can experience significant runoff into surrounding ground and down pathways. The raised bed absorbs water and contains potential runoff. As long as you have good-quality soil in place, your raised bed will retain water and be the perfect growing environment for your plants.
Do Vegetables Grow Better in Raised Beds?
Yes! Not only will vegetable gardening be less work, but you can also grow for longer as the soil warms earlier in spring and dries faster, so autumn and winter crops can be planted sooner. Your cultivating soil will be of better quality, richer in nutrients, translating to flourishing crops. You’ll have fewer weeds, no invasion of grass, and less invasion from rabbits and other critters (if these are a problem in your area). The soil will not be as compacted, meaning earthworms and microorganisms do better.
Those vegetables that perform best in raised beds include root vegetables, onions, garlic, tomatoes, leafy greens, and potatoes.
So what are you waiting for! Experience a whole new level of enjoyment and satisfaction when you adopt the use of organic raised beds – and reap the many benefits they offer.