David Hall was digging his allotment recently, keeping an eye on an adjacent plot holder who was constructing raised beds. Taking a breather, it crossed my mind whether I should adopt such a system, would it prove more productive and less hard work?
To construct a raised bed for vegetables, you’ll need two boards measuring about 1in x 4ins x 4ft long and two others of the same thickness and height but as long as you like, 6ft or 8ft would be a good choice.
Nail or screw 12in pegs near the end, and flush with the top, of each board. With the pegs facing inward, use a mallet to drive them into the ground, so the boards form a rectangle. A long spirit level is useful to ensure that they are level.
Now fill the bed with well rotted manure, compost and top soil.
If you're unsure about constructing one yourself, several manufacturers have easy to assemble raised beds made from excellent quality timber.
Are They More Productive?
First impressions of a plot using raised beds for vegetables are good. Growing areas are physically separated from paths and everything looks very neat and orderly.
The theory is that, as the bed is deep and the soil not compacted, the roots have lots of room to grow downwards.
Hence vegetables can been sown in blocks instead of rows and grown closer together, significantly increasing yield.
Easy access is also guaranteed since the bed is only 4ft across and can be tended from either side. As you don’t tread on a raised bed, the free draining soil structure should be maintained and only a little forking before planting is required.
You can also control in a much more effective way the soil’s pH. Most vegetables prefer neutral to acidic growing conditions. So if you have naturally alkaline soil, by raising the bed you can create a more acidic environment.
As for maintenance, add a layer of compost or manure every spring and mulch to discourage weeds. A crop of green manure at the end of the season would be useful.
Are There Any Negatives?
There are only a few drawbacks. If you buy the boards, there is the initial expense and effort in creating the beds. You may need a friend to help with the work.
Since the soil should have good drainage, extra watering may be necessary especially for seedlings and young crops.
Not all vegetables can be successfully cultivated. For example, potatoes need earthing up and staking runner beans in soft soil isn’t satisfactory.
However, when all these factors are considered, raised beds certainly do make sense. Increased productivity will soon outweigh the initial expenditure and, unless you enjoy digging, they are very much a labour saving idea.