Can you please help me with calculating the amount of soil (and other ingredients) needed to fill 4’x4’ garden bed (12”deep). I am buying 2 of these for my parents to put in their back yard. They will grow mainly vegetables, salads and herbs.
Can you please recommend a formula for good quality soil mixture and maybe a supplier that can deliver the basic ingredients in bulk?
What a wonderful gesture to provide your parents with raised beds to grow vegetables, greens and herbs! Of course, a good quality soil mixture is essential to start growing edibles in their backyard. You are aware that having appropriate soil for growing edibles is important–the amount of soil that will be needed can be calculated easily with this formula. It seems that you will need approximately one cubic yard of soil for both beds–ordering from a local supplier who delivers one-cubic yard enviro-bags would be the most economic solution. Some in the Toronto area offer mixtures such as Gro-veg Premium Blend which contain mixtures of compost, topsoil, and other organic materials suited to growing vegetables.
If the garden beds will be placed on existing lawn, dig and turn over the lawn (grass-side down) within the box area–the grass will eventually break down and the existing soil will provide a base for the new soil. Once the garden beds are established, additions of compost will be needed to amend the soil to retain moisture and provide nutrients for the plants. Encourage your parents to start a compost bin. In the fall, add chopped (mowed) tree leaves directly to the soil; they will break down over the winter and provide nutrients.
For further information, see: https://savvygardening.com/the-best-soil-for-a-raised-garden-bed/
If you are interested in doing more reading, local author Tara Nolan’s book, Raised Bed Revolution: Build It, Fill It, Plant It… Garden Anywhere (Cool Springs Press, May 2016), is really terrific.
All the best for a successful veggie/herb garden this year.