By Cheryl Harrison, Master Gardener
My casual interest in scree gardens became a burning desire to have one (you know the feeling) when I went on my first Peterborough Master Gardener garden tour in 2017. We visited a nursery that had amazing demonstration scree and rock gardens. I was smitten!
A scree garden is found in nature. Small rocks and gravel travel down the side of a mountain because of the freeze-thaw action on the rockface. This material accumulates in crevices, on rock shelves and at the mountain base. It drains well and is home to plants that survive on only rain. Scree gardens are good for areas that are already rocky, sandy or do not have a lot of soil to begin with. However, they can be replicated pretty much anywhere with a raised bed to ensure good drainage. A raised bed is especially important if you have clay soil. Choose a sunny site that is not overshadowed by trees. You don’t want the constant challenge of leaf litter on your garden. As when creating any new garden, make sure all weeds and grass are removed before you start.
Different sources quote different mixes for the actual garden “soil” to use in your raised bed. I used what I had for mine. This consisted of some larger rocks in the bottom, and then a layer of gravel, then mostly sand, and gravel mixed with some garden soil. The sand, gravel, and garden soil mixture was used to fill the spaces in the rocks up to the top of my raised bed. Remember that you are trying to replicate nature so your scree must have excellent drainage and not be overly rich.
I chose plants that I knew could take dryer soils and thrive in my Southern Ontario garden with it’s summer heat and high humidity. There are lots of lists of potential scree and rock garden plants on the internet. Some local nurseries carry plants that will thrive in well drained conditions. Once that you have found plants that will grow, as with any garden, choose plants that will give you the look that you want ie. colour, texture, height and spread.
In her book “Pocket Gardening”, gardening writer Marjorie Harris talks about how to maintain the scree and rock gardens. Ms. Harris recommends topdressing the garden with leaf mold and coarse sharp sand or 3/8 inch gravel when plants are dormant which means very early spring or late fall.
Have fun with it and make your garden into what makes you happy!