A raised bed gives you an eye-catching feature, a better view of your plants and, by lifting them up, less strain on your back when tending them. Learn how to make a raised bed in one day.
Creating a square or rectangular timber-framed raised bed is easy, especially if the pieces are pre-cut to length. Buy pressure-treated wood, which will last for many years, or treat it with preservative before you start. If the bed is to sit next to a lawn, make a brick mowing edge.
This project should only take you about a day.
Dig out strips of sod wide enough to accommodate the wood (image 1). Pressure-treated wood is an economic alternative to rot-resistant hardwoods, such as oak, or consider buying reclaimed hardwood.
Lay out the wood where you want to use it. Check that it is level (image 2) (use a plank of wood to support a shorter level). Check levels diagonally, as well as along the length.
Make sure the base is square by checking that the diagonals are equal in length (image 3). For a perfect square or rectangular bed, it is a good idea to have the wood pre-cut to size at your local gardening or hardware store.
Using a rubber mallet, gently tap the wood so that it butts up against the adjacent piece; it should stand perfectly level and upright according to the readings on your level (image 1). Remove soil as needed.
Predrill holes through the top and bottom of the ends of the wood, and into the adjacent pieces, to accommodate a couple of long, heavy-duty coach screws (image 2). Secure the wood with the screws.
Arrange the next set of wood on top of the base; make sure they overlap the joints below to give the structure added strength (image 3). Check with a level before screwing them together.
For extra drainage, partially fill the base with rubble - rocks, broken pieces of terra cotta and other similar materials (image 4). Then add topsoil that is free of perennial weeds. Fill the bed up to about 3 inches from the top with soil, install your plants then mulch with bark.
Raised beds are ideal for growing vegetables, fruits and herbs. They provide better drainage on heavier soils and a deeper root run for crops like carrots and potatoes. Raised beds also lift up trailing plants, such as strawberries, which helps to prevent rotting. If you buy fresh topsoil that’s guaranteed weed- and disease-free, your crops will have a better chance of growing well.
Grass doesn't grow well too close to a raised bed, since the soil tends to be dry and any overhanging plants create shade. A strip of bricks, sunk slightly lower than the level of the sod, creates a clean edge to allow for easy mowing.
Using a spare brick to measure the appropriate width for your mowing edge, set up a line of string to act as a guide (image 1). Dig out a strip of soil deep enough to accommodate the bricks, plus 1 inch of mortar.
Lay a level mortar mix in the bottom of the trench as a foundation for the bricks (image 2). Set them on top, leaving a small gap between each brick. This design is straight, but mowing edges can also be set around curves.
With a level, check that the bricks are aligned and positioned slightly below the surface of the lawn (when set in place, you should be able to mow straight over them). Use a rubber mallet to gently tap them into position (image 1).
Use a dry mix to mortar the joints between the bricks, working the mixture in with a trowel (image 2). Clean off the excess with a stiff brush.
Excerpted from Garden Design
©Dorling Kindersley Limited 2009