Because representative data must be collected over many years, follow these rules when selecting the site for your observations.

1. Choose an unshaded place, away from buildings, trees, or any other obstacles. (The minimum distance from the base of any obstacle should be at least two times the height of that obstacle).
2. As much as possible, choose a place away from footpaths, sidewalks, and roads.
3. At weather stations, plant the cultivars about 12 to 15 meters (40 to 50 feet) away from the station to avoid any interference with the station instruments.
4. Choose a place where you can observe the plants easily each day.
5. Choose a place where there is no risk of the plants being trampled by people or animals.
6. Choose a place where excessive amounts of snow do not accumulate from drifting or plowing.
7. As much as possible, choose a level surface; if you have a hilly landscape, avoid, if possible, the low areas that can unduly delay shrub development in the spring.
8. Plant in soil commonly found in the area; avoid planting in soil, such as a garden, that has received heavy applications of manure or compost.
9. Leave at least 5 m (15 feett) between plants.
10. Choose a location that will not create any special microclimates (such as frost pockets or windy slopes) for the plants.