The beginning of any landscape or garden design is making a map of your garden — a plot plan. Many techniques and tools are available to make the job faster and more accurate, but they take some specialized skills to operate. The method described here is very simple, and uses a minimum of equipment.
You’ll need graph paper divided into squares. Paper with 10 squares per inch is readily available and easiest to work with. This type of paper is called “cross-section” graph paper in stores that sell drafting supplies. The lines are in a light blue ink that does not reproduce, so copies made from it don’t show the lines. The type of paper that has every tenth line in bolder ink is easier to use.
To avoid counting lines on the graph paper, purchase an engineer’s rule. One of the scales on this rule is in tenths of an inch. The rule makes measuring on the graph paper simple, and can also give accurate measurements that are at angles to the graph paper lines.
You will also need a clipboard and pencil to make the map in your yard, and two tape rules: a landscaper’s 100-foot tape rule to measure long distances and a carpenter’s 16- or 24-foot tape rule for shorter distances.
Landscaper’s tape rules are more flexible than carpenter’s rules. The end of the tape has a loop through which you can poke a screwdriver to pin it to the ground, and a hook if you find something to hook it over. However, it’s easier to have a helper to hold the far end of the tape. If you are working alone, bring along a large screwdriver to pin the end of the tape rule down.
There are two methods for mapping your yard: a simple method that makes use of existing straight lines, and triangulation, which takes longer but does not rely on straight lines.
The Simple Method
Use this method if you have a reliable straight line, such as the back wall of your house, to measure from. Use that line as the foundation line for your mapping. Draw a line at one edge of the graph paper to represent that line. If you have a second edge perpendicular to it, draw that line on another edge of the paper.
As an example, let’s say your are using the back of your house and a fence at the edge of your back yard as edges. Measure the length of the back wall of your house and lay that distance out at one edge of the graph paper. Draw it lightly with pencil as a straight line. Later, you can add porches, bay, chimneys, and anything else that interrupts that straight line.
Next, measure the distance from the corner of the house to the fence you are using as a second edge. Use that distance to locate the fence on the graph paper. Measure the length of the fence and draw it on the paper.
From the foundation of these two lines, you can locate any point in your back yard as a distance from the house and the fence. For example, to locate a tree growing in your back yard, measure the distance from the house to the tree. Make a light line on the map to represent the tree. Now measure the distance from the fence to the tree. Another line at that distance will cross the first line where the tree is located.
That’s all there is to it. However, there are a couple of tricks that make the job easier. One trick is to lay the long tape down next to whatever you are measuring, then measure distances in the other direction with the carpenter’s tape. For example if you wanted to locate all the plants in a shrub border, you would lay the tape from the back of the house all down the length of the border. Then walk down the border locating each plant. You can see its distance from the house on the long tape rule, and use the carpenter’s tape to find the distance from the fence.
Another trick is to locate objects and then measure from them. For example, if a path runs straight from your house to a gate in the back fence, lay out that path and then use it as another edge to measure things from.
To lay out a curve, measure to points on the curve, then fill in the space between them freehand. For example, you could lay out a long, curved path by locating 3 or 4 points along its edge as dots on your plan. Then, looking at the path, draw it in. It won’t be perfect, but will probably be close enough. The more points on its edge you locate, the more accurate the plan will be.
But what if you don’t have a line to use as a second foundation line perpendicular to your house? You can stretch a string to use as the perpendicular line using the carpenter’s 3–4–5 trick. This is based on the fact that if the height and width of a right triangle are in the relationship of 3 to 4, the hypotenuse will be 5.
In practice, peg the end of a piece of string to the ground at the back wall of your house, and measure off 4 feet or a multiple of 4 feet. Make a mark or tie a knot at 4 feet. Now measure 3 feet or a multiple of 3 feet from the peg along the wall of the house. At the 3-foot mark, pin down the end of your long tape with the screwdriver. Stretch the tape out 5 feet (or a multiple of 5 feet), pull the string tight, and mark the spot where the 4-foot string and the 5-foot tape cross. Push a marker into the ground at that spot. Now take the end of the string and walk it to the back of the yard. When you’re there, align the string with the marker you pushed into the ground. The string is now perpendicular to the back wall of the house. You can peg down the second end and use the string as a foundation line.
Triangulation
The second method of locating objects on a map doesn’t rely on any straight lines at all. It measures the distance to an object being located from any two known points, locating it as the point of a triangle.
To use triangulation, select two fixed points across the yard from one another. They can be a telephone pole and the corner of a fence, two corners of your house, or any other points. Measure the distance between them and lay them out on your graph paper. Call them point A and point B on the map.
Peg down the end of the long tape measure at point A and walk around the yard, measuring the distance to any object you want to locate. Take notes in a notebook of the distances from A. Next, move your tape to point B and note all the distances from the second point.
Your notebook should look like this:
| A | B | |
| End of retaining wall | 63 | 15 |
| SW corner of garage | 22 | 35 |
| ‘Chicago Peace’ rose bush | 5 | 58 |
As you work, sketch in all the points you want to locate. This sketch will not be accurate, but will help you remember roughly which objects are where. You can also take notes by labeling points on the sketch, then using the labels in your notes instead of naming the point.
Back inside, use your notes and the engineer’s scale to lay out each point on a clean sheet of graph paper. First locate points A and B the right distance apart. Then set a drafting compass on the engineer’s scale to the distance to an object from A.
Using the example above, to locate the end of the retaining wall, set the compass to 63 feet. Then place the point on point A and make an arc on the paper with the pencil end. Now set the compass to 15 feet and make another arc from point B. The place where the two arcs intersect is the location of the end of the retaining wall.