Annual flowers are often mentioned in garden talk. Literally the term defines things that last for a year. Annual plants grow for a year or less from germination to death. Some germinate, grow, flower and set seed in a single season or less. Annuals do not die down or go into a semi-dormant rest period then continue to grow as do biennials or perennials. They race through their short lives growing quickly, often flowering profusely so they can set as many seeds as possible before they fade away. This is why trimming faded flowers before they can set seed – dead-heading – keeps them in bloom longer. Annuals are good ways to add lots of color quickly to a garden. They also make excellent fillers for empty spaces in newly planted gardens while larger-growing plants are still small.
You will find plenty of annuals to choose from in garden centers. They are often offered as ‘bedding annuals’ or ‘bedding plants’ Because annuals only last for a single season you don’t have to worry what growing zone you are in. None will last for more than the season so it isn’t important how hardy — cold tolerant — they are. In warm-winter areas, annuals that prefer cool, but frost-free temperatures will grow well during those winter months. Some examples would be stock, pansies, calendula, ornamental cabbage and primrose. If you live where summers do not get extremely hot or where weather is variable, these annuals will do fine in spring, summer and autumn. Portulaca, sunflower, marigolds and annual sage do well in summers with high temperatures.
Some plants that are short-lived or temperature sensitive are grown as annuals even though they would last longer in favorable conditions. You will find snapdragons will sometimes last more than a year with a mild winter. Flowers like Gerbera daisies, chrysanthemums, gazanias and hibiscus are some plants often used for only a single season of bloom where they will not survive cold winters even though they are not annuals.