Raised bed vegetable garden
Raised Bed Vegetable Gardens
Learn important steps in planning and preparing for a raised vegetable garden bed, such as size, spacing, and building materials. See some different ways to create a raised garden bed.
A raised bed vegetable garden is a garden which is built on top of the ground. It may be contained by some sort of wall (wood, stone, brick etc) or it may just be soil piled several inches high on top of the ground.
photo credit: GonnaFly
The raised vegetable beds can be any shape or length but you need to be able to reach the whole bed from the sides without stepping in the garden bed. The soil in the beds may contain some of your native soil or may be composed of imported soil, compost, manure, or a combination. The vegetables are planted much closer together than in the traditional row vegetable garden enabling intensive gardening and giving a bigger harvest in a smaller area - making a raised vegetable garden the ideal choice for a small yard.
What would you like to learn about raised vegetable gardens?
Clickable table of contents
Advantages and disadvantages of raised vegetable gardens
Raised vegetable garden design
Building a raised vegetable garden
Other good stuff
Benefits of a raised bed vegetable garden
Picture credit: morguefile.
- great for a small space - a raised bed vegetable garden will enable you to grow your plants closer together keeping wasted space to a minimum. This provides a larger harvest in a smaller area. So if you have only room for a small vegetable garden, a raised bed may be an ideal option for you.
- less weeding - Another benefit of this closer planting is that less light is allowed through and less room for those weeds to start, reducing the weeding task.
- reduced moisture loss from the soil - again because of the closer planting
- you control the soil in your garden - a raised bed vegetable garden can be a great asset when you have poor soil. Because you build up extra soil on top of the ground, it will not matter if your soil is too rocky, too sandy, too clayey, too acid or just plain and simply too bad. It is the soil that you put into the raised beds that counts. This means that you can even build a raised garden bed on a concrete slab or on your patio!
- extended growing season - the raised garden beds warm up earlier in the Spring giving your seedlings a head start.
- garden maintenance can be broken into smaller segments - you don't need to weed the entire garden, just one bed. Or your children could be responsible for a bed each.
- soil compaction is reduced - the beds should be narrow enough to reach all parts of the bed without the need to step in your garden for planting, weeding, watering or harvesting.
- a raised bed may be easier on your back - an advantage for gardeners with arthritis or for elderly gardeners and if they are raised to the correct level, they can even be accessible to people in a wheelchair.
- watering is more efficient - you need only to water where the plants are growing and not the spaces between your vegetable rows.
- it is relatively easy to attach a framework of flexible PVC tubing to a raised garden bed over which you can place either clear plastic to create a greenhouse effect to extend your growing season even more, or some netting to prevent pests from getting to your vegetables (those birds just love my strawberries!).
Disadvantages of raised garden beds
Maybe I'm a little biased since I use raised vegetable garden beds myself. However these are the disadvantages that I can see:
- weeding has to be done by hand - but as I mentioned before, there is not a huge amount of weeding necessary
- there needs to be a bit more up front garden planning - because the plants will be closer together you will need to take into account the height of plants so that the taller ones won't shade the shorter ones etc.
- the up-front costs may be a bit more than a conventional garden, but in the long run the increased harvests will outweigh those initial costs.
- in hotter regions, the beds may dry out too fast in mid summer and may require large amounts of water. Mulching the vegetable garden with an organic mulch such as hay or straw will help combat this problem.
Raised vegetable garden design
Design your own raised vegetable beds plan
The raised bed layouts pictured below were made by using a handy garden planning program. If you have a different sized yard, want to plant different vegetables or want to try out some different layouts, you can download a free trial of this garden planning software here.
Important things to consider in your raised bed vegetable garden design
Careful consideration needs to made on where you will situate your raised bed vegetable garden. As with all vegetable gardens, your raised vegetable garden needs to be situated in a position that will receive at least 6 to 8 hours of sun per day.
Each garden bed should be no wider than 3 or 4 feet (.9 - 1.2 m) to allow you to reach into the middle from either side. If you can only access the bed from one side (if you are building next to a wall or fence say) the bed should only be about 2 feet (.6m) wide. The length doesn't really matter, but you probably won't want the beds too long because you won't want to be making a really long journey just to get to the other side of the garden bed. The best depth for the raised bed is about 6-12 inches (15-30 cm) but if you want to sit in a chair to garden, a height of 2 -3 feet (.6-.9 m) may be better. If you are building your raised garden bed on a hard surface such as a patio or concrete slab, you will be better off with a depth of 12 inches (30cm).
The pathways in between the beds need to be wide enough to work in comfortably - at least 2 feet (.6m) wide, preferably 3 feet (.9m). Do you need to allow space for a wheelbarrow? A wheelchair? A lawnmower? Two people walking side by side? Pathways may be paved (with bricks, stones or paving stones) or mulched (with gravel, leaf mulch or straw) or covered with a living cover (such as grass, chamomile or creeping thyme). If you are paving your paths you may wish to make your paths a width which will not require too much cutting of the stones. (eg Don't make the path 4 Â½ bricks wide. Instead make it 5 bricks wide (or 4 bricks wide) otherwise you'll have to cut many bricks in half.)
A great way to increase the yield per square foot is to use a tower, trellis, fence, vegetable cage or other sort of support for your vining and sprawling plants such as tomatoes, cucumbers and sugar snap peas. In this way, they will take up a lot less space on the ground. Growing vertically means that the plants may dry out more quickly, which can be an advantage in preventing fungus diseases but also may mean that the vegetables will require more water.
Sample raised vegetable garden bed plans - for an 18' x 18' area (324 sq ft) - click on pictures below for bigger viewClick thumbnail to view full-size
How can you arrange a 4'x4' raised vegetable bed?
Vegetable Garden Plans Click on this link to get some ideas for different types of vegetable gardens you can fit in a 4'x4' square garden bed. These plans can be adapted to be bigger or smaller.
Square Foot Gardening
A type of raised vegetable garden
Square foot gardening is a form of raised vegetable beds. Each garden bed is divided by string, wood or some sort of straight line into square foot sections. Each square foot is then planted with 1, 4, 9 or 16 of the one type of vegetable (depending on the recommended spacing).
Here are some pictures of square foot gardens. Click on each thumbnail for a larger view.
Find out more about square foot gardening
Square Foot Gardening Square foot gardening is a popular method of gardening which allows closer planting of vegetables, herbs and flowers, producing a bigger crop in a smaller space with less work. Find out how to make a square foot garden here.
Use the WORD technique to increase productivity and decrease weeds and pest attacks:Wide rowsOrganic methodsRaised bedsDeep soil
Building a raised vegetable garden
Materials for building raised garden beds
What's the best material for building the garden bed walls? Here is a list of different materials with some of their advantages and disadvantages:
* Free-form - no walls
- easy to set up
- relatively easy to move to a different location
-soil can easily erode with heavy rain
-doesn't look as neat
-sides need to be sloped which takes up more room.
* Untreated timber
- looks neater
- contains the soil
- garden bed walls are not very wide, taking up valuable ground space
-fungi and insects can degrade some untreated wood very quickly outdoors especially because the wood is in contact with the soil. You will probably have to rebuild your garden beds every few years. To prevent such rapid breakdown, you could line the bed with plastic before filling with soil or seal the wood with linseed oil to add some resistance.
- a raised bed made from unprotected timber near your home could serve as a pathway for termites or carpenter ants inside.
- some rot resistant woods (eg red cedar, cypress, redwood) may be expensive and there may be a limited supply in some regions.
Raised Garden Bed sustainably harvested wood (4'x6'x9")
Raised Garden Bed 100% western red cedar (48"x48"x13")
Half-Log Raised Garden Bed sustainably harvested wood (4'x4'x9')
Two-Tiered Raised Garden Kit North American cedar (4'x8'x10.5" & 7"))
Garden Bed With Trellis cedar wood (48"x48")
Raised Garden Kit cedar wood (48"x48")
* Treated lumber
Timber treated with pentachlorophenol
- DON'T USE - likely to damage plants severely
Pressure treated lumber
- The jury is still out on whether or not this is safe to use in your raised vegetable garden beds. If you want a truly organic garden it should not be used. If you are concerned about the chemicals leaching into the soil, and you want to use treated wood, you could line the sides of the bed with plastic before filling it with the soil.
* Wooden railroad ties or sleepers - treated with creosote, a coal derivative
- last for a long time
- you can sit on the ties while gardening
- not too expensive
- the fumes from the creosote may damage nearby vegetables. If used in a greenhouse (an enclosed environment), the vapors may damage or kill all the plants in there. (Note: even though the creosote may leach into the soil, it will not be absorbed into the plant.)
- your clothes can be stained with black tar stains if you sit or lean against the ties especially in warm weather
- wider than timber and therefore take up more space
- very heavy to work with
- can still be infested with termites.
* Bricks, concrete blocks or stones
- not damaged by insects or fungus.
- can use recycled materials
- can easily arrange into most shapes and sizes.
- the beds can look really attractive.
- no nasty chemicals
- can plant herbs or other small veggies in the large holes of concrete blocks
- if the wall is sturdy enough, you can sit on it while working in the garden bed
- heavy to work with.
- if only 2 or 3 layers high you need not have to use mortar - but then the blocks can be knocked out of place.
- if much higher, you will need to use mortar so this means more work and the gardens will be permanently in place.
- holes in bricks are a great sheltering place for snails!
- wider than timber and therefore take up more space.
- can be expensive.
* Plastic "lumber" or "masonry"
- last longer than timber
- lightweight but strong
- easy to assemble
- more expensive
- fake (!)
2-Rail Raised Bed Garden Kit orcaboard (4'x4')
6 Panel Tiered Resin Raised Garden Kit resin construction (48"x48"x16")
Raised Garden Bed Kit uv-protected high-density polyethylene 2 of (4'x4')
- can be relocated
- no nasty chemicals
- absorbs more heat during the day
- the walls of the garden bed are narrow, not wasting space
- can be quite deep - good for those who don't want to bend so far
- can't sit on the side
- absorbs more heat during the day which may not be good if you live in a hot area
- may rust, unless you use stainless steel
Above borders courtesy of www.grsites.com
Galvanized Steel Raised Garden Kits
Building a raised garden bed from lumber
Here are some instructions for building a raised bed out of lumber from scratch if you would rather build your own. Note: If you have a problem with moles or gophers, you may wish to put some sort of screening on the base of the box (before the soil goes in) to keep them out.
A raised vegetable garden built from concrete blocks
Notice the trellises built into the holes in the concrete blocks. Other holes could be filled with soil and used to plant small vegetables, herbs or flowers.
Building a free-form raised vegetable garden - (no walls)
Keyhole raised vegetable garden
This video shows how people in Africa are able to get a great harvest from their garden (a keyhole raised vegetable garden) where once they struggled to grow anything. You can see how they made their keyhole raised vegetable garden from rocks. For more information and written intructions go to Send a Cow; scroll down to Keyhole Gardens and how to make one.
Hugelkultur raised garden bed
Hugelkultur raised garden beds are basically piles of wood (logs, branches, twigs, even whole trees) with some soil on top. Once they are established, they require very little watering.
Pictures of hugelkultur raised garden beds. Click to enlarge.
Building a raised vegetable garden with railway sleepers - ... this gardener recommends not doing it
Pictures of raised vegetable beds
click thumbnails to enlarge the photos
Here is a selection of raised vegetable bed pictures. Notice what the garden beds are made from. One has been made in a recycled child's swimming pool (probably with drainage holes drilled into the bottom). One is made from concrete blocks and sandstone. Another has been made from colourbond steel and cable ties.
Raised vegetable garden bed soil
To get a higher yield and plant your veggies and herbs closer together, you will need a very fertile soil. You should use lots of old manure (e.g. horse or chook) and compost. This is what I now use in my no dig gardens.
If you plan to get topsoil trucked to your place, do your research first to ensure that is good quality top soil - not too sandy, not too clayey. Sandy is better than clay though since it can be improved by adding compost, peat moss and composted cow manure. Also be careful that you are not importing someone else's weed seeds. It would be best to mix this imported soil with generous amounts of manure and compost to make sure that it contains a good amount of organic matter.
In my raised beds I use a mixture of home-made compost, mushroom compost (bought in bags), some well-rotted chook manure, some blood and bone and coir bricks which have been rehydrated.
If you are buying your soil / compost and need to calculate how much you need, you will need to determine length times width times depth for each of your beds (if your beds are square or rectangular). For circular beds you will need to determine depth x radius x radius x 3.14 (remember pi?) (and remember the radius is the measure of halfway across your circle).
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