Annuals come and annuals go. There are cool season annuals for winter. There are warm season annuals for summer. Really though, there are all sorts of annuals that are not annuals at all. Most are some sort of perennial that has the potential to last longer than a single season. Only a few popular ‘annuals’ would necessarily die after blooming and producing seed, within a single year.
To be clear, true annuals last only a single year. They probably germinate from seed early in spring, and grow quickly. They then bloom in spring or at least by summer, and subsequently produce seed. Once their seed has matured and been dispersed, their job is done. They finally die in late autumn or winter. Annuals from deserts are even faster because of the harshness of the weather.
Many large-flowered sunflowers are true annuals. They are finished once their seeds mature. They will not bloom again. Even if they wanted to, they would not survive through winter. Petunias should be annuals, because they also die over winter. However, it is possible for them to survive winter in a semi-dormant state, and regenerate and bloom again the following spring and summer.
Realistically, it is not practical to salvage petunias for a second year. It is easier and more efficient to plant new ones. Yet, it sometimes happens, particularly in mixed plantings where old plants can get cut back while cool season annuals dominate in winter. Alternatively, lanky old stems can get buried with only their tips exposed. These tips might grow as new plants the following spring.
Cyclamen are cool season annuals that have been dieing back for summer. They usually get removed by now. However, in mixed plantings, some of their fat tubers can survive through summer to regenerate next autumn. For what they cost, they are worth salvaging! Primrose, chrysanthemum, impatiens and the various fibrous begonias are all worth salvaging through their off seasons.
Fibrous begonias may not know what their off season is. Those that bloomed through winter might be looking tired by now. If pruned back, they could regenerate as warm season annuals. Those planted in spring might look tired by the end of summer. If pruned back early enough in autumn, and protected from frost, they might grow enough before winter to work as cool season annuals. Cutting them back and waiting for regeneration may not be much more effort than replacing old plants with new ones, and is less expensive.
Tony Tomeo 
That’s useful to know – we have planned several of the plants you mention this year so I’ll keep my fingers crossed they come back next year. Our primroses definitely have survived for several years now
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Much of their survival depends on the climate. Of course, in colder climates, fewer of the warm season annuals survive through winter.
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There is a perennial petunia you can get over here now. Have you heard of them?
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So far, all of our petunias are sold as warm season annuals. However, I have grown some for a few years, and there are some with smaller flowers that are popularly grown as perennials. Million Bells is a perennial that looks very much like petunias with small flowers.
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The perennial ones here are popular in hanging baskets, and look very pretty
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Most of those I see here are already planted in hanging baskets. I have seen them in six packs or 4″ pots only rarely.
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They make good ground cover too…
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I particularly like how they cascade over the edges of planters and stone.
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I found that some plants that are sold as annuals in the north, make it through the winter here. We plant petunias in the winter and the summer heat kills them off.
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Wow, now that is totally backward. However, that is how snapdragons are. They are cool season annuals where winters are mild, but warm season annuals where summers are mild.
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I wonder if annual sunflowers actually occurred in nature, or if they are the result of human effort.
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Many wild sunflowers are annual. They are also prolific with their seed because birds take most. Some of the fancy breeds do not produce many viable seed, and if they do, the seed is not true to type.
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Reblogged this on Tony Tomeo and commented:
Due to an inability to locate some of my old articles from nine years ago, I will recycle articles such as this, which already posted to this blog four years ago, through June and at least part of July.
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