Best Native Plants for Boulevard Gardens
Characteristics of Drought Tolerant Perennials
Source: Toronto Master Gardeners, Drought Tolerant Perennials: A Toronto Master Gardeners Guide
Drought tolerant perennials share many of the following characteristics that, when established, enable them to withstand periods of prolonged drought.
Many have silver or grey foliage, resulting from a coating of fine hairs on the surface of their leaves. These hairs reflect light and heat, and provide shade, thus reducing the amount of moisture lost to the atmosphere. Waxed or furry leaves, designed to keep plants cool and retain moisture, are also characteristics of many drought tolerant plants.
Leaf size also affects moisture loss. Many plants that have adapted to dry conditions have small or narrow leaves to minimize the amount of exposed leaf surface. Thick leaves are another common adaptation. For this reason, fleshy, succulent plants, such as Sedum, are popular choices for dry locations.
Root systems also affect drought tolerance. Perennials with large fibrous roots or deep tap roots are able to reach down into the soil to collect water and also store moisture for future use.
Most drought tolerant perennials grow in sunny locations and it is important to understand how light conditions are classified.
Full sun – plants require at least 6 hours of direct, late-morning/afternoon sun
Partial shade – plants need 3 to 6 hours of morning or afternoon sun, but should be shaded from the hot, midday sun.
Full Shade – plants can thrive with less than 3 hours of sun. A bright location that receives no direct sun would be classified as full shade.
Blooming Boulevards uses locally-sourced drought-tolerant native perennials for our boulevard gardens, and most also withstand salt. This year's available selections are listed below:
Height:3 ft, Spread: 2 ft, Spacing: 2-3 ft. Flowers July-Aug. Flourishes in sunny sites with moist humus-rich sandy loams. Plants tolerate heavier loams, clay, gravelly or calcareous soils. They also prosper in heat, humidity and drought. During extended hot dry weather lower leaves may wither. In garden soils organic matter can be added to help retain moisture.Rabbits may nibble the foliage and stems.