There are many ways of growing vegetables; in fields, beds, trenches, flooded areas, sunken beds, rows, vertically, square foot beds, grow bags boxes and pots, even in nutrient rich water.
In our area people generally rotivate their land each spring and plant the vegetable gardens out in rows like a mini version of field cultivation. I followed the local way in our first year here but found that our light stony soil was non the better for it; the nutrients and humus I added were just getting washed away during the torrential rains in autumn. So now I prefer a raised bed system; for our sloping growing land with soil that is light, shallow and stony over rock, a raised bed system is what works for us.
Benefits of using a raised bed system
- Soil depth is increased as mulches are applied each year
- Soil does not get compacted because it is not being walked on
- Soil is kept aerated and weeded by hoeing the top few inches
- Soil structure is improved by keeping it undisturbed (digging light soil just turns it to dust).
- Soil fertility can be improved as and where needed and in rotation
- Water is conserved by tailoring irrigation to the needs of the crops in each bed
- Planning and rotating the growing area is easier because beds are fixed
- Easier to provide specific soil requirements for plants with special needs.
- On a sloping site a raised bed can level the growing area
- Work is reduced by digging soil only once and thereafter leaving it alone
- Taller edges can be made to protect and support some plants
- It just looks tidy! when i go down to the kitchen gardens it is easy to walk between the beds and harvest what i need.
For us the benefits of a raised bed system outweigh the downsides. Raised beds are less suitable to the light sandy soil and dry conditions we have here, as raised beds have a tendency to dry out faster. However, the fact that the beds won’t be dug over again helps to maintain the soils structure and by top dressing with muck and compost twice a season and mulching in summer we are able to increase the fertility and water retention of the soil making it less prone to drying out in the long term. The bed edges also help to protect the top soil from being whipped away by the long, dry summer winds.
Edging the beds
I did try to just visually mark the bed boundaries because I wanted to be able to change the layout each year but I found that the top dressings and nutrients got washed away in the heavy rains. The higher the planting areas got and the lower the paths got the more got washed away and the growing areas became smaller in time. So I ended up edging the beds.
Ours are not the smartest looking beds, most are edged with whatever i can get my hands on; old planks, the round end bits of trees left over from milling, flat stones, I even tried making some woven edges – far too pretty for my garden, rather pointless and they only lasted a single season but they did look cute (see pic above). I have learned to just make the best use of what I have around without causing myself extra work.
Adapting growing methods to climate and land
We live in a mountainous area which has unfortunately been given over to the mono-culture of pine trees but it would have been covered in a mixed deciduous forest with shrub and low growing plants. This year I plan to start fencing off some new areas of land to try growing edibles in a more natural forest-like way. No fixed beds just a layering of planting that will mirror the way plants grow in nature with trees, bushes, climbers, perennials and annuals (if they self seed) all taking their place. I want to see for myself which is more productive and uses the least water; the permaculture way as advocated by Bill Mollison or the fixed bed intensive growing the way i do it now. Gardening is about adapting and being open to find out what works for each piece of land and climate see Kate’s picture of some clever irrigated sunken vegetable beds in India @ Hills and Plain.
Revised and adapted from my original post 26/3/2007