All plants have a hardiness zone rating. This rating describes how likely the plant is to survive through the winter in a region. The higher the hardiness number, the warmer the winter must be for the plant to survive. Likewise, a small number (closer to zero) indicates that the plant can survive much lower temperatures.
The hardiness zone also describes the average winter temperature in an area. Here at Arts Nursery, we are a zone 7. Therefore, given a normal west coast winter, any plant with hardiness of less than 7, SHOULD survive. Always treat these zones as guidelines, not rules. A quick cold snap can really wrech havoc on plants that have not yet gone dormant and extended periods of cold can dry out plants that should normally survive.
Plants with a higher zone than 7 are described as tender and will probably not survive our winter unless given appropriate protection or brought indoors. You could also treat these plants as seasonal annuals.
Please note that other types of hardiness ratings exist. For example, most plants from the USA use either the USDA zone system or the SUNSET system. The USDA system is one zone warmer than our system so be careful when looking at the numbers. The Sunset system evaluates winter temperatures, summer heat and geographical variation.
If you have any questions about plant hardiness, please give us a call at 604.882.1201 or visit us in person at Arts Nursery Ltd.