Flowers Canada proudly serves the cities in Canada, Ottawa, Vancouver, Toronto, Montreal, Calgary, Edmonton and all other cities and surrounding suburbs. We can deliver your order the same day, as long as you order the flowers and gifts before 1pm receiver time. We choose only the freshest, top quality flowers.
Each region of the world has its own set of physical conditions. Topography, the levels of precipitation and evaporation, amount and arrival of heat cold, days of frost and length f growing season are all factors that help create our individual climates. Ways of quantifying and charting the weather has been the preoccupation of scientists, farmers, and zealous gardeners down the centuries and, with exploration and technical advances, many countries have developed detailed and accurate mapping systems that categorize conditions, based primarily on temperature, into climate zones.
The system employed in flora follows the map developed in the 1960s by the United States Department of Agriculture (USDA), which divides the country into twelve designated hardiness zones. Each zone is separated by 5.5 degrees Celsius, beginning with the Arctic at 45 degrees Celsius and ending in the equatorial tropics at 10 degrees Celsius. These average minimum temperatures for each hardiness zone are based on the minimum temperature recorded each winter season over a period of 20 years. The original USDA map has since been expanded to cover much of the rest of the world.
The zones are not uniform. There are cooler and warmer areas within a zone depending on its most northerly or southerly part. Topographical features such as mountain ranges, plains, and proximity to the coast all affect temperature, and therefore, whether that area falls in one zone or another. For this reason, a zone on a map may suddenly dip into an area surrounded by a warmer zone, or curve up in a thin line along a coast.
The main purpose of the USDA map is to tell us what zone we are in, and therefore indicate what plants can be grown in our part of the world. Secondly, it allows us to look at other regions or countries in the same zone, and also surrounding zones, and see what plants do well in those areas. Essentially, climate zones provide an indication of a plant's "hardiness", that is, its ability to survive cold weather, including frost and ice.
The zones are based on average low temperatures only, and do not provide additional information about extremes and variations in low temperatures for a region. In some regions temperatures can be much warmer and much colder than the average from year to year. Other factors also need to be considered. For example, if a garden is in or near an urban center, situated on a hillside above a valley floor where cold air is likely to settle, or tends to experiences breezes when other areas are still, winter minimums are likely to be a bit warmer than surrounding areas. The opposite is true if a garden is situated at a valley bottom out of the wind. Here, temperatures are likely to fall during the night. These are all characteristics of what is called a microclimate and can be taken advantage of.
It is important to reiterate that the zone maps only indicate the average lowest temperature. When a plant in this book is rated to a specific zone, it means that horticulturists have succeeded in that zone, even with the reasonable yearly fluctuations in winter lows.