It is important that we know where we want to locate and position our raised beds, but before we do that lets do a little house-keeping. Before we start-building raised beds, we need to do a garden reconnaissance ( not militarily, of course ) and check the lay-out of our surroundings, especially where we would like to set up our raised garden beds. We need to know critically, if there are any electrical cables buried underground. That is the most important element of this task, if we are planning to do a little digging in our backyard or back garden. After we have eliminated that risk , we can then check to see if there are are any other utilities running through our premises. Items like water pipes, waste water drains or sewage outlets, telephone or internet cables, gas pipes etc etc. Once we have established all of these facts, it is then safe to begin digging and preparing to make our raised bed gardens.
After we have erected the raised bed frame, it is imperative that we dig the ground inside the frame thoroughly. We now have semi-prepared this space and we can easily determine the quality of the soil within the raised bed frame area. The idea of this is firstly, to check for any tree roots, rocks and any foreign materials that would disrupt the growing area and secondly to ensure that the fresh topsoil that we will infill to the bed frame will integrate with the existing soil easily. This practise is known as ‘double digging’ and is a means of getting the soil ready for our vegetable planting.
It will result in better aeration and will prevent compaction of the soil, when it comes to the time for planting. Soil preparation is key to having a healthy, productive and high yield return from our raised beds. As soon as we have that task complete, we are now ready to top-up the raised beds with a good mixture of high grade top soil, good organic compost or farmyard manure and some peat. We also need to add small quantity of soil enricher like bone meal, fish meal ar any good type of organic fertiliser, which will serve to enhance the quality of the raised bed soil.
How tall should a raised bed be ?
This is a question that is asked so frequently and so often, it is impossible to answer definitely, so the answers will vary from time to time. In short these bed depths could vary from 6-8″ all the way up to 20-24″, again depending on what we have decided to plant, or what materials we had to hand when constructing the raised bed frame . If it is our standard casual vegetables like cabbages, lettuces, onions, herbs etc, a bed depth of 6-10″ will suffice. However if we decide to plant larger vegetables like potatoes or fruit bearing shrubs, then obviously these raised bed frames need to be a little deeper.
Raised bed auxillary supports;
Again before we begin planting, we must recognise that some vegetables that will grow reasonably tall, these will need to be staked and supported, so we need to factor this into our plans. This is not a big concern in the greater scheme of things as bamboo sticks and canes are available at all garden centres and are reasonably priced. It is easy to make a temporary frame from 2″ x 1″ lengths of timber to support the bamboo canes. Just a small word of caution and advise to add here, which is; lets take it that the bed is located in an open area and we have decided to plant some of the climbing vine vegetables like tomatoes, peas, squash etc etc, the chances are that these tall vegetables will, in all probability, be battered from strong winds from time to time.
In that case I would locate my raised bed against a south facing wall, (garage or boundary). That in turn would enable us to mount and affix a trellis up against this wall and would thus be far more secure against the elements. With this system our vegetables would then be semi-protected at least and have a far greater chance to flourish and thrive. When planting, always adhere to planting instructions and ask for advise at your friendly garden centre.
So to summarise;
- Check our surroundings,
- Eliminate all risks,
- Establish a safe, sunny location,
- Construct the raised bed frame,
- Prepare the raised bed ground,
- Infill with good topsoil,
- Decide raised bed depth,
- Decide plant selection.
- Plant and harvest.
Happy gardening to all,
Cheers Phil Browne.
“Tickle the earth with a hoe
and she will laugh with a harvest”
Douglas William Jerrold