From Seed to Seed: |
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Different types of life cycles
Annuals. One could argue that the entire life of a plant
is geared toward
one thing: reproducing. For annual
plants, the production of flowers and seeds is the culmination Other common garden annuals
Biennials. Biennial plants complete their life cycles over two growing seasons (bi = two). During the first season, these plants grow only foliage, commonly a low-growing rosette of leaves. In the second growing season, they form flowers and produce seeds. After the second season, the mother plant dies. Common biennial plants include foxglove and Canterbury bells. Did you also know that parsley, cabbage, kale, Brussels sprouts, carrot, and celery are also biennials? We usually harvest them during their first season of vegetative growth so we never actually see the flowers. Perennials. Perennial
plants continue to grow and flower for more than two years, and many will
live for decades. As with annuals and biennials, perennials produce flowers
that, if successfully fertilized, form seeds. The difference is that the
mother plant does not die after producing seed. Since we define the life
cycle of a plant as the time it takes for a plant to go from seed to seed,
a perennial's life cycle can vary widely. For many common perennials,
completing a life cycle usually takes from two to perhaps five years.
For example, if you plant a coneflower seed, you'll get only foliage the
first few years, with flowers and seeds being produced in subsequent years.
If the first seed is formed in the third season, then we would say that
the plant has a three-year life cycle, from seed to seed. The word perennial is commonly used to describe long-lived herbaceous plants-those with green, non-woody stems. In temperate regions, most perennials die back to the ground in the winter, then sprout from their underground growth in the spring. Strictly speaking, woody plants are also perennials, since they grow for many years. Commonly, however, a distinction is made between woody and non-woody perennials. The word perennial is reserved for herbaceous, non-woody plants. Woody plants whose aboveground parts persist through the winter are categorized as shrubs, trees, or woody vines.
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