Sun Mapping Your Garden the Easy Way

Sun mapping your garden will help you buy the right plant and place it in the right location. Plants grow best if you give them the right amount of sun, and the only way to do this is to know how much sun each of your garden spaces gets. In this post, I will show you a very easy way to get this information and develop your personalized sun map.

KISS in the Garden

KISS stands for Keep It Simple Stupid. I am always amazed that some gardeners go out of their way to make our hobby difficult. Things work so much better and are more enjoyable if you keep it simple.

There are some electronic gadgets, like the Sunlight Calculator,  available that claim to make sun mapping easy, but they are simply not needed. All you need is paper, a pencil, and your hand.

Why Make a Sun Map of Your Garden?

Sun mapping your garden will help you select the right place for each plant.

You just bought a new plant that likes to grow in shade, and you are walking around your garden looking for a place to put it. You are looking for a shady spot, but if it is very cloudy, you can’t tell which part of the garden is shady – it’s all shady today.

Even if the sun comes out, how do you tell the difference between shade and part-shade? You can’t, unless you stand there all day.

Many gardeners plant in spring or fall when trees do not have leaves. It is very hard to identify a shady spot at this time of year.

As a new gardener or an experienced gardener in a new location, it is very helpful to have a sun map of the garden. Then, when you are looking for a place to plant your new special purchase, you won’t make a mistake.

Sun, Shade, Part-shade, and Part-sun

Have a look at a plant label, or check a plant online, and look for the light recommendation. In virtually all cases, the best information you get is sun, shade, or part-shade/part-sun. Nobody tries to fine-tune this to give you the exact hours the plant likes because that is too difficult, and it does not matter. Plants are not that fussy, and other factors like water can be more important.

What is the difference between part-shade and part-sun? Some people try to define these more precisely, but it is really not necessary. I consider them to be the same thing – use KISS.

The sun is at least 6 hours of direct sun (no shadows).

Part-shade is 4-6 hours of direct sun.

Shade is less than 4 hours of direct sun.

All you need to do is assign one of these categories to each area of your garden.

Make A Map of Your Property

This is much easier than it sounds. Take a piece of paper and sketch your property. Graph paper is easiest to use, but any sheet of paper will work. It is helpful to get things in scale, but that is not necessary. What is important is that you can easily identify each existing garden area as well as any potential future gardens. It is a good idea to include the house, shed, patio, fences, etc, because these will help you identify the location of gardens.

Here is an example of one I did. It could be made better with a tape measure and ruler, but that is not necessary. Make five copies of the map once it is complete.

Measuring Sunlight

Pick a day that is sunny with limited cloud cover. Go to the garden and take note of where the sun hits the ground directly and where you have a shadow. A shadow line is the separation between these two areas.

Take one of your maps, draw in all of the shadow lines, and then shade in the shadow areas.

Repeat this 4 times during the day to see how the shadow changes throughout the whole day. Using 9:00, 12:00, 3:00, and 6:00 works well. Make a map each time you do it.

Some people record values every hour, but that is not necessary. We don’t need that kind of accuracy to know where to put plants.

Best Time of Year

Shadows change with the time of year, and this effect depends very much on where you live. There is almost no change close to the equator. The sun rises and sets in the same spot all year long, and therefore,      the shadows are the same all year long.

As you move away from the equator, the point at which the sun rises is different throughout the year. The location at midday also changes. In my garden, the sun is almost overhead at noon in the summer, but it’s much nearer the horizon in winter. This seasonal change means that shadow lines also move as the seasons change.

If you are near the equator, you can measure shadows at any time of year, provided deciduous trees still have their leaves. For areas that see a lot of seasonal change, it is best to make the measurements near midsummer.

Prepare a Final Sun Map

Take the 5th copy of your map and place the other 4 maps around it. Pick a point in your garden and check all 4 of the maps to see if it is sunny or shady.

If at least 3 of the maps show it as sunny, mark it sunny.

If at least 3 of the maps show it as shady, mark it shady.

If it is neither sunny nor shady, mark it as part-shade.

You can use colored pencils to color code things, or just add letter designations – whatever works for you.

Now repeat this process for other areas of your garden. When you are finished, your whole garden will show one of three designations – sun, shade, or part-shade. You are now ready for planting.

How to Create a Beautiful Shade Garden

Now that you know where your shade garden is, you will enjoy this video.

If the above link does not play, try this one: https://youtu.be/gXt0pzZjXSI