What is site analysis?
Site analysis is the basic process of getting to know your existing conditions and assessing what will stay, what will go, and what should be modified.

A site analysis involves a series of direct field observations that are drawn onto a base map. A base map serves as a foundation to guide your garden design, and will help you choose the right features and plants for your site conditions, and keep everything in scale.

The following information will help you later when you develop your base map. To learn more about drawing a base map, see Do I Really Need Drawings?

How do I get started analyzing my site?

Size : Climate : Neighborhood : Light : Soil : Drainage : Traffic : Existing Features

Determine the dimensions of the site and where any buildings are located on the property.

Locate the legal property corners if possible (these are usually staked with a metal pipe driven into the ground until it’s almost flush and it often takes a metal detector to find them). Use large tape measures to measure the distance between the corners and the buildings, walkways, large trees, etc. The more detail you can plot in, the better your map will be. See directions for measuring square footage.

Tip: Most properties have a legal document called a "plat of survey," held by the owner, along with the deed or title, which shows the legal property boundaries and the relative relationship of any platted buildings. If you can start with this document, this will be the most accurate way to begin your base map; otherwise, you will need to develop your own basemap by measuring the site.

Kids love to measure! If the group can use measuring tapes, have them develop the base map. Let them work in small groups and then compare the various base maps produced to assess accuracy. Discuss the issues of accuracy in measuring. A good tie to the concept of replication in the real-world science experiments!

Tip on measuring: If the group is too young for formal tape measures, have them use their arms, feet, or whatever is handy as units of measurement to “measure” the site.

Tip on drawing to scale: Explore the marking on a ruler and talk about how you can draw a place that is 20’ wide on a much smaller piece of paper. If the real object measures 16 arm lengths, can we draw it on paper as 16 finger widths?

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Climate and microclimate
Determine your growing zone and climate.

Where you are located in the country dictates your climate, or the overall weather and temperature conditions you have. Climate affects when your first and last freezes occur, and what activities you may be able to do during a given season. For more information on determining your zone and climate, go to Understanding your Climate.

Ask your students to take temperature, light, and wind measurements at different locations around your campus; see how the measurements are different or similar. Discuss the weather patterns for your region and how the variations of your schoolyard affect the conditions that plants may face. (For instance, is there a protected courtyard area?) Ask them to create a diagram of the school’s microclimate conditions.

Tip: If you are studying weather as part of your curriculum, you may want to have students repeat these measurements throughout the year to create an annual climate log.

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Neighborhood context
Determine how the property relates to the surrounding neighborhood.

Go out and do a walking survey, really look around the neighborhood and see what is going on, even at various times of day.

Ask yourself:
  • What’s next to the property on each side and what goes on there?
  • Are there certain traffic patterns, either from cars or from people walking?
  • What do you need to consider about the landscapes of the adjacent properties?
  • Are they all very tidy and neat – or are some unkempt and in need of attention?
  • Are there businesses or neighbors who will have a view into your garden – or you into their property?
  • Are there views you want to screen? Think about the neighbor’s perspective: Are there areas that should be screened to give neighbors better privacy or screened for noise?

Draw the features of the adjacent properties on your base map and be sure to note any views to emphasize or screen.

Take kids on a neighborhood walk with their journals and let them record their observations; if they are too young to write, have them draw pictures. Discuss the things they saw when you return to class.

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Determine the light conditions of the space.

Observe the light at various times of day. Typically full sun is > 6 hours per day, shade is < 2-3 hours, and part shade is in between – but the intensity and seasonality factors should be considered as well.

Ask yourself:
  • Does the site have full sun, partial sun, or shady conditions?
  • Do these light conditions exist based on seasonal or year-round shade due to buildings/evergreens?
  • Is there shade in the morning but full sun in the afternoon?
  • Is the light filtered through the canopy of a tree overhead?
Tip: Afternoon light and southern or western exposures tend to make the light more intense, so even if shorter in duration, it may still be considered full sun.

For older students, it may be possible to have them actually measure the light with light meters used for photography, an example of using the “tools of science”. For younger students, simply focus on how sunny it is in various areas. Watch the shadows move across the schoolyard throughout the day; visit each hour and mark where the building shadows fall.

Tip: Explore how the sun moves from east to west and how the time of day or the angle of the sun affects the intensity of the light. This is a great way to link the study of the earth’s rotation in relation to the sun to a practical application; that is, looking at the amount of sun your garden will receive at different times of the year.

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Determine the type of soil.

Get to know your soil by taking a small handful and squeezing the soil between your fingers.

Ask yourself:
  • Does it feel gritty? This indicates sand.
  • Does it feel smooth like clay? This indicates a high clay content.
  • Does it feel somewhere in between gritty and smooth, with a crumbly texture? This indicates a loam soil that contains a balanced mix of the sand, silt, and clay particles.
  • Do you see little pieces of leaves and bark? Is there a clean, earthy smell to the soil? This indicates a good amount of organic material, also called “humus.”

Tip: Soil may be different in different areas of your site, so sample it in several spots.

What’s in soil, anyway?
Soil is composed of mineral and organic components as well as air spaces. The mineral particles may be sand, silt, or clay, with sand being the largest particle and clay being the smallest. All soils are some combination of these three (3) mineral particles.

The organic component refers to the bits of decomposing plant material in the soil; this is a healthy aspect to the soil as it provides nutrients and improves drainage.

What is compost and when do I need it?
Compost is simply decomposed plant material that we mix into the top 6-8” of soil to improve the texture and nutrient capacity of the soil. The most common problem with soil is that it doesn’t have enough organic material in its composition. This is why we add compost. Heavy clay soils may also need to have sand added, but most soils just need extra organic matter. If you have your soil tested, the analysis usually includes a section with recommendations for modifying your soil, which may include the addition of compost.

Let them get dirty! Have teams collect soil samples from locations scattered throughout the site (say points 1-10), and then do “feel” tests on each of their labeled samples. How do they describe and rank each sample? Put your sample into a jar and fill it with water; let the jar sit overnight to settle and examine how the layers of particles have distributed in the morning. The different particles will create separate layers. Clay will sink to the bottom, with sand above it, and silt on top. Organic matter will float to the surface and form a layer there. Students can then clearly estimate percent sand, silt, and clay and compare it with the predictions they made when they collected the samples.

For older students, have them test pH and basic nutrient rates for N, P, and K (nitrogen, phosphorous, and potassium) back in the classroom (simple kits are available at garden centers and through www.kidsgardening.com).

Tip: Send a representative sample off to your university extension service for actual testing; this usually costs less than $20.

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Determine where your water will drain.

Surface and internal – the two main types of drainage. Surface drainage has to do with the way water runs across the site. Internal drainage is the way water runs through the soil.

How do I know where the water drains?
The best way to analyze surface drainage is simply to observe the water and where it goes during a rainstorm. There may be soil channels in the ground where erosion has occurred, and you (and your students) will probably have a good idea of where it “puddles” when it rains. Draw the drainage patterns on your base map.

To measure internal drainage, students can conduct a percolation test. Percolation refers to the rate at which water drains, or “percolates,” through the soil. Dig a small hole, about 1’ x 1’ and fill the hole with water and monitor how quickly the water drains. If the water disappears in less than 30-50 minutes, the soil is very well-drained and probably has a lot of sand in it. If the hole still has water in it after several hours, your site has poor drainage and likely has high clay content. Draw any areas of poor or excessive drainage on your base map.

Let kids go out and look at the site during a rainstorm (under umbrellas, when there is no lightening!); work in partners so one student can hold the umbrella and one can draw the patterns of surface flow. Have them conduct a basic percolation test as described above.

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Traffic and use patterns
Determine how people move across the site and make use of the space. Draw these patterns as arrows on your base map; the larger the arrow, the heavier the flow of traffic. If there is a building entrance or exit that gets especially heavy use, make note of it on the base map.

Ask yourself:
  • Are there walkways that people use?
  • Do people cut across the grass and wear new paths in the turf? (These are all called “desire paths.” It is usually best to accommodate them in your design, as it is difficult to stop people from using these short-cuts.)
  • Are there spaces where people gather to play or hang out?

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Existing features
Determine the buildings, sidewalks, trees, shrubs, manholes, fences, light poles, utility boxes, playground equipment, and anything else that is a permanent feature on your site.

Measure these items from a known location, like the building or property corner and draw them onto your base map in scale. Label all the features and make notes about the conditions; if a sidewalk is broken and needs repair, state that on your base map.

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