Shining a light on shade

Turn over a plant label and amongst other things it will tell you what kind of light the plant needs to do best however what does that really mean? In the first of two articles looking at shade in the garden, I start off by explaining the different kinds of shade.

Eight Shades of Garden

Shade, when it comes to a plant, is quite simply the absence of direct sunlight but there is still some light available.  That light might come from reflected surfaces, ambient light (from the sky itself), light that filters through the canopy of a tree or other sources.

However, because the sun moves across the sky, rising in the east and setting in the west, a plant over the course of the day can go from being in the shade to being in direct sunlight to being back in the shade again. In other words, it isn’t quite as easy as that – light and so shade changes over the day and then over the year.

Some plants need as much direct sunlight as possible whereas others are quite happy with permanent shade and when it comes to plant labels or details, they will always indicate the kind of light (or shade) that the plant will do best in.

The reality is that most plants will grow in a sun/shade setting which is not its ideal, but will never be at their best.  I see this a great deal in gardens – plants that have been put in places where the light isn’t right and so it is either out of shape or underdeveloped.

So, let us decipher (according to the RHS) the various types of shade that you are likely to encounter when light preference for a plant is being described:

• Full Sun – An area that receives more and 6 hours of direct sun per day (at midsummer).
• Partial Shade – An area that receives between 3 to 6 hours of direct sun (at midsummer).
• Semi-shade – The same as Partial Shade
• Medium Shade – An area that receives 2 to 3 hours of direct sun (at midsummer).
• Dappled Shade – An area that receives full sun however its light is filtered by a thin canopy of leaves or branches from overhead trees.
• Light Shade – An area that is open to the sky (so nothing overhead) but receives very little or no direct sunlight (as the sun is blocked by nearby walls, fences or trees).
• Deep Shade – An area that isn’t open to the sky (for example under dense tree cover) or receives less than 2 hours of direct sun.
• Heavy Shade – As Deep Shade

The important thing to note about the number of hours of direct sun mentioned above is that this is based on the day in the year when there is most sun and for us in the UK that is going to be the 21st June. 

So before putting the plant you have ear-marked for an area in your basket – which of the shades above apply to that area and does that agree with the label?

In second part I explain a bit more about how the aspect of your garden affects the light it gets, how a south facing garden may not be as good as it sounds and how you plot the changes in shade in your garden over the day and year.