Actually, Denver is Zone 6, by USDA/National Arbor Day standards.
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Shrubbery, or shrubs, are often used to line walkways, create hedges and frame gardens. Their versatile nature is due in part to having a lower height than many trees at full maturity, the variety of sizes and colors, maintenance requirements, as well as their hardiness. Hardy shrubs can be described as those that can withstand extremes in temperature, exposure, and moisture conditions, as well as varied types of soil.
The U.S.D.A. (United States Department of Agriculture) has divided the U.S. into multiple zones according to temperature range. This is referred to as the USDA Plant Hardiness Zone Map. This zone map can be used as a guide when deciding what to plant in and around a garden, however, hardy shrubs may do well in a geographical zone other than its native location.
As an example, Mr. Gardener of Denver, CO is located in zone 5 according to the Hardiness Zone Map. His physical location is subject to cold temperatures, freezing and snow. Mr. Gardener wants to plant a hardy shrub such as the hydrangea, but knows there are several species of hydrangea to choose from. The Oakleaf Hydrangea shrub has a hardiness zone of 5-9. This would be appropriate for Mr. Gardener to plant in his garden. However, the Bigleaf Hydrangea has a hardiness zone of 6-9 and this plant may not thrive in the Denver climate as the Oakleaf species may.
A variety of hardy shrubs are suitable for a wide range of hardiness zones, including the Black Chokeberry (zones 3-8), the Arrowwood Viburnum (zones 3-8), the Black Knight Butterfly Bush (zones 4-9), and the Pink Cascade Tamarix (zones 2-8). A quick search with your favorite search engine will tell you what zone you live in and can help you identify which hardy shrubs will be best for your location.
It is important to consider some logistics before purchasing hardy shrubs. How large is the area where the shrub will be planted? At maturity, will the shrub be contained within the available area? If the shrub can withstand the winter, are other conditions such as the soil type and exposure compatible with the shrub? Is the intent to provide color during the summer or fall months, to provide a hedge, a border, or to line a pathway? How often does the shrub need pruning? Once these questions can be answered, picking the right hardy shrubs for your home landscaping project becomes an easy, fun, even artistic pursuit.
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