A raised bed garden is a simple enough concept. The earliest were just rows or blocks of deep, finely tilled earth raised in mounds above the ground.
It was discovered that the curved shape increased the number of plants one could grow. However, without any support around the mound, rain would wash the soil away, and so people began to construct low (usually wooden) walls around them to keep the soil from leaching away. Concrete or natural stone are also options if building your own, although these days such walls can also be bought from garden centers.
The initial outlay in time, money and hard work when creating this type of raised garden bed sometimes discourages people, although once the construction is finished the last years and are easy to maintain. There are definite advantages to this method that is worth considering.
If your soil is poor, such gardening allows you to develop high-quality areas of soil for growing. This earth will warm more quickly in the spring, and is easier to work; it also drains better. Such plots are made for accessibility and ease of access.
They can look very attractive and can be used for both flowers and vegetables. You can tailor the size to your particular garden.
They are generally easier to maintain, as the close-growing does not encourage weeds, but weeding must still be done, and by hand, not with a hoe as is used on flat plots.
For those who are not physically able to cope with larger flat plots, deep beds require less work in digging over. You can work on clearing or weeding one at a time.
Not all vegetables are suited to this type of gardening, as they require more growing space, but root vegetables thrive as long as the soil is deep enough to accommodate their growth.
Spring onion, beetroot, radish, onions, parsnip, cauliflower (you will have to pick when the heads are still small.) garlic, lettuce, onions, French beans, swedes, potatoes, and tomatoes will all do well. The yield and quality are higher than in flat plots.
In most allotments and any gardens it is now common to see raised garden bed plots, and once constructed, they can give you many years of healthy and prolific growth with very little maintenance.