The best size and number of beds to order depends partly on how much food you want to grow – the more beds you have and the larger they are, the more food you can grow.
After more than a decade of experience installing and growing food in raised garden beds in a variety of settings, we have some additional general guidelines for choosing the size and number of beds to install.
LENGTH
We generally recommend that beds are between 1 metre and 3.5 metres long, although they can be any length that you like and the plants don’t seem to have a preference. If beds are more than around 1.7 metres in length we will generally include a horizontal brace for additional stability to prevent the bed from bowing. Also keep in mind that it is more cost effective to have one longer bed than two shorter beds as the longer bed uses less timber than the two shorter ones.
WIDTH
For most people to have easy access to the plants in the bed, we’ve found that the ideal width for a raised garden bed is:
- 90cm if you have access on one side of the bed only
- 120cm if you have access from both sides of the bed (can be up to 140cm depending on your reach).
If your ability to reach is limited, you may want to consider reducing the bed to 70cm wide.
HEIGHT
- Wicking beds should be at least 40cm and no greater than 80cm. The ideal height is 60cm. If you’re interested in the why and how of designing wicking beds, you can read more in our page on How to Make a Wicking Bed.
- Raised beds that contain soil only (ie. not wicking beds) can be as low as 40cm on a hard surface like concrete or pavers or 20cm when placed directly on soil.
- We recommend a maximum bed height of 60cm if you want to grow taller plants like tomatoes as it can get hard to reach the top of the plant if your bed is any higher.
You may also want to consider your own height, and whether you prefer to sit, lean or stand and if you want to avoid bending while working in your garden bed.
- a 40cm high bed is about the height of a standard chair, ideal for sitting
- a 60cm high bed is about the height of a bench stool, ideal for a sitting/leaning on (good for for wheelchair users)
- an 80cm high bed is good if you want to avoid bending over, ideal for leaning on.
PATHWAYS
You want to leave enough space between your beds to ensure easy access to your garden. We recommend the following pathway widths between beds.
- a minimum of 50cm
- 70cm for wheelbarrows
- 90cm for wheelchairs and walking frames.
There are other factors that you may want to consider (eg. crop rotation) but this is a good beginner’s guide. If your requirements are more complex than this we also offer a permaculture design service.
