Early Spring Flowers
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Have you ever noticed that the first spring flowers emerge in one particular area of the garden, often blooming before the snow melts? The reason may be microclimatic. Hi, I'm Dave Thurlow and this is The Weather Notebook.

A "microclimate" is the climate of a small area, such as a backyard, park or garden. Microclimates can vary over short distances due to the presence of rocks, trees and walls, factors which alter the wind, moisture, temperature and the absorption of sunlight.

For example, on the southern side of a building, the ground receives more warming sunlight than the shady north side. Direct sunlight plus its reflection off the building often keeps the earth close to it warm and free of snow.

Generally, building materials -- rock, brick, wood, or concrete -- collect and hold the solar heat, releasing it slowly during the night. This keeps minimum temperatures in an acceptable range while, only a few feet away, temperatures fall too low for sprouts to survive in the early spring.

Not only is the temperature of the soil in that sunny patch warmer than more shaded areas, the soil should be drier as well -- not totally dry but not saturated. Warm soil, strong sunlight and the right moisture content provide good conditions for young house hugging plants to thrive.

If you understand your garden's microclimate, you can enjoy early spring flowers by planting in optimum locations. A weather eye and a green thumb -- they go together.

Thanks to contributing writer Keith Heidorn. Visit our website at weathernotebook.org. Support for The Weather Notebook comes from Subaru, the beauty of all wheel drive.