Garden Climate and Temperature

Plants have evolved all over the world, adapting over the course of time to local conditions, whether temperate or tropical, wet or dry, loamy or rocky, sunny or shady. Plants that failed to find a niche became extinct and vanished. These days, we bring plants from diverse climates and communities into our gardens. Even when we try to design with native plants, we know that they, too, have diversity in their history. Their seeds may well have been brought to the region hundreds of years ago by animals, water, wind, and native people. Each plant species has a range of conditions under which it will thrive, other conditions under which it will merely survive, and unique limitations that will cause its death in hostile conditions.

Temperature

Microclimates in your yard allow you to grow plants that might not otherwise thrive in your zone.
Microclimates in your yard allow you
to grow plants that might not
otherwise thrive in your zone.

Heat and cold influence plant survival. Understanding temperature in your garden will help you find the varieties of plants that can thrive for you, especially those plants that normally live for more than a year. Conditions in your garden are influenced by your region's climate, including frost dates, and your garden's unique exposure. Plants can be grown outside their natural climate if you provide warmth to tropical plants in winter (for example, growing a lemon tree in a greenhouse in Massachusetts) or cold to plants from temperate climates in winter (for instance, treating tulip bulbs with weeks of refrigeration before planting them in Georgia). Consider both heat tolerance and cold tolerance before your select your plantings.

Seasons

Some regions, such as the Midwest, are hot in summer but icy cold in winter; some are either hot or cold all the time; and others are mild or moderate most of the year. In some regions, summers are very dry but winters are wet. Others are changeable from year to year. Even though we cannot do much about local weather, we can observe its patterns and choose plants that are naturally suited.

Microclimate

Within every garden, you can find areas with different kinds of exposure to the elements. These are called microclimates. Even a small deck will usually have several microclimates. The part closest to the house may get more reflected light if it faces west or more shade if it faces north compared to other parts of the same deck. In larger areas, differences are even more pronounced.

Plant a Windbreak
Reduce the volume of strong winds by using a layered assortment of plants as a windbreak. Wind can knock down and dry out plants and generally make it harder to get the garden to grow well. Layered plants -- taller trees with shade-tolerant shrubs planted beneath them -- create an irregular barrier that gently slows wind. Solid fences, in contrast, allow wind to slip up and over and swirl back in on the other side.

Within these special niches, some plants may bloom earlier or longer into the season or be more likely to freeze or overheat. South-facing slopes or sides of buildings tend to have a longer growing season than nearby areas. Spring flowers there may bloom a week or two earlier than those in a cooler part of the garden. Although a south-facing area may be warm on sunny winter days, the rapid drop in temperature from a bright winter day to a cold night may be too extreme for some plants. The cooler, shadier, north-facing exposure is better for marginally hardy plants and those that are prone to drying out in winter.

Wind

How windy is your garden? Strong winds can snap off branches and cause plants to dry out faster than they can take up water to replace its loss. When selecting plants for windy areas, try varieties that originated in windy climates because they have developed resistance through strength and flexibility. Leathery, stringy, or waxy leaves are another adaptation. Protection from wind may be needed for other garden plants. Windbreaks, walls, buildings, and berms (raised mounds of earth) help alter wind patterns in your garden.

The USDA's hardiness zone map shows the hardiness zones for the United States and Canada, which will help you chose the right plants for your climate. Go to the next page to see the hardiness zone map.

High-Speed Gardening: Entranceway Evergreen
Spruce up your entranceway with a potted evergreen. It will look great all year -- without major digging. You can try this project at any time of year on a paved or unpaved surface.

Decide how large and tall a feature you want to add, and choose a container that complements your home. Purchase a dwarf conifer or evergreen plant of the appropriate shape and size (its nursery pot should be about half the size of your chosen container). Be sure to base your selection on the type of light in your spot (a good garden center can help you).

Set the container in its new home, and add a layer of potting soil to it. You should add enough so that the soil line of the potted plant ultimately falls about an inch below the container's rim. Take the evergreen out of its pot (fan out the roots if they are bunched up) and set it on top of the soil layer, making sure there are no big air pockets below it. Surround the evergreen with soil partway up. Add groundcover plants (such as ajuga or liriope) near the surface if you like; space them evenly around the shrub. Firm everything in and water. Correct the soil level with more potting soil if necessary, add mulch, and water gently one more time. Keep the soil steadily moist but not soggy, and fertilize from time to time according to package directions.


Looking for more information about gardening? Try these:
  • How to Start a Garden: Find out how to get your garden started.
  • Planting a Garden: Once the planning is done and the soil is ready, the next step is planting your flowers or vegetables.
  • Annual Flowers: Learn about annual flowers, which continue to bloom throughout the growing season.
  • Perennial Flowers: Find out about perennial flowers, which return to grace your garden year after year.
  • Gardening: Learn the basics of successful gardening.