Raised Garden Beds & Planter Boxes

Should I choose an open-bottom bed or a planter on legs?

An open-bottom frame sits on the ground; a planter on legs supports its own growing box. Decide where the bed will go and how you want to reach the plants before choosing its height.

How much soil depth does the planter actually provide?

An 80 cm-high planter can contain a growing box less than 20 cm deep. The legs lift the plants closer to you; they do not give the roots 80 cm of soil.

• For a planter on legs, use the inside base-to-fill-line measurement.
• Leave some space below the rim for watering and mulch rather than filling to the very top.
• For an open-bottom frame on concrete, count only the growing space you supply; roots cannot continue into soil beneath it.

Does the garden bed have a bottom?

Some beds are open frames; others have a supported base or water reservoir. On garden soil, an open bottom connects the new bed with the ground beneath. On concrete, water still needs an escape route and roots have only the growing mix inside the bed.

• Keep an elevated planter’s drainage outlets clear and use a growing mix suited to containers.
• A plastic liner without drainage can turn a bed into a waterlogged container.
• Gravel is not a replacement for drainage holes. A layer of stones also takes up some of the available growing depth.
• Arrange drainage so water does not pool against a wall or run across the main walking route.

How much growing mix will I need?

For a rectangular growing space, multiply its inside length, inside width and intended soil depth in metres. The calculator below uses centimetres and converts the result to litres for you.

Length × width × fill depth × 1,000 = litres (dimensions in metres)

• Use the growing box’s inside measurements. Legs, raised internal floors and reservoirs reduce the space available for soil.
• Allow space below the rim for watering and mulch. Growing mix can settle after filling.
• The box calculation is an estimate for straight-sided rectangular spaces; curved ends and sloping walls change the capacity.
• For a multi-pack, calculate one bed and multiply by the number of identical beds. For a configurable kit, use the layout you will actually assemble.

Can I reach the middle without stepping into the bed?

An 80 cm-wide bed reached from both sides puts the centre 40 cm from either edge. Against a fence, the same bed requires an 80 cm reach to the back. Mark an outline on the ground and try reaching it before committing to a long row of beds.

• Leave a path where you will harvest, carry a watering can or move a wheelbarrow.
• If you garden from a seat, a shelf below the planter can reduce knee space. Look at the frame as well as its height.
• Place fixed beds before filling them. Wheeled planters still have load limits and are much heavier with wet mix and water inside.

Which material and pack size am I ordering?

The range includes galvanised steel, timber and polypropylene planters. Steel frames offer long planting runs; modular plastic boxes form smaller combinations; timber options include compact and trellis designs. Separate pack quantity from configuration: “2-in-1” can mean two assembly layouts, not two identical complete beds. Other listings are genuine two-, three- or four-bed packs. Use the package contents and assembly layout to understand what will arrive.

Is a self-watering planter maintenance-free?

No. A reservoir stores water, but it still needs filling and the overflow must work. Newly planted seedlings need moisture where their small roots are growing. With ordinary raised beds, keep the watering route close enough that tending the far end does not become a chore. Check beneath the surface rather than watering only because the top looks dry.