Flowers that come back up from their roots every year in the springtime are called “perennial” flowers. Some of the best perennial flowers to grow in a garden are peonies, daylilies, coneflowers, and hollyhocks.
Perennials are a flower garden's backbone, providing beautiful color, texture and form. They are easy-care, dependable performers that come back every year.
Simply put, annual plants die in the winter season so you must replant them every year, while perennials come back every year so you only plant them once.
Annual flowers grow for one long season, often into the fall, then die with the onset of freezing weather. With perennials, the above-ground portion of the plant dies back in freezing weather, but re-grows from the base and rootstock the following spring to bloom again.
The short answer is that annuals don't come back. Plants that flower and die in one season are annuals—although many will drop seeds that you can collect (or leave) to grow new plants in the spring.
As rapid growers—averaging about 2 feet of growth per year—larger varieties of hydrangeas can reach up to 15 feet tall. Applicable in growing zones 3 to 9, hydrangeas are a low maintenance plant that will return year after year with proper care.
Are marigolds perennials or annuals? Actually, both! Most marigolds are annuals, but a few are perennials. Marigolds self-seed so they may appear to be a perennial when in reality, they are just coming back from seed.
True geraniums are hardy perennials that return to the garden each year with a flush of handsome leaves. In spring and early summer, they can be covered with flowers that are pale pink, blue, purple, violet, rose, magenta or pure white.
In ideal conditions, petunias can come back each year. But frost will kill these plants. Some gardeners have success overwintering petunia plants indoors. But most simply plant new petunias each spring.
Brightly-colored flowers that are tubular tend to produce the most nectar, and are particularly attractive to hummingbirds. These include perennials such as bee balms, columbines, daylilies, and lupines; biennials such as foxgloves and hollyhocks; and many annuals, including cleomes, impatiens, and petunias.
Most varieties of forget-me-nots are perennials, returning and spreading each year through both seeds and stolons. The plant has a strong reputation for spreading, especially in areas near the Great Lakes in the US, where they're considered an invasive species.
But no, the agave americana is definitely from Earth. It's also known as a century plant because it only blooms once every 100 years (roughly) and then dies.
Daylily (Hemerocallis)
Affectionally called the "perfect perennial," Daylilies survive through almost anything — fluctuating temperatures, irregular watering and so on. They come in a variety of colors and sizes, so you can find the right option to suit your garden or landscaping.
The agave americana plant is known as a century plant because it typically blooms once every 100 years at the end of its life cycle.
The average life expectancy of a geranium is about two years, and although they will last much longer than that, they tend to get woody and the blooms diminish. Luckily, propagation is easy with geraniums. Simply take four-inch stem tip cuttings with at least two pairs of healthy leaves.
If you have potted geraniums too large to be brought inside you can consider leaving them outside says David Taylor. 'If you have really large potted pelargoniums outside and have a south facing wall you can chance putting the pots up against this for the winter.
Annual geraniums (Pelargonium hybrids) are amazing — they grow and bloom beautifully from spring to frost without a lot of fuss. Then you dig them up in fall, put them in a cardboard box or a paper bag to store over winter and these tough little plants will take off and grow again the following spring.
In the Arid Greenhouse at the Chicago Botanic Garden, Agave ocahui is known as the century plant because people used to think it flowered only once every 100 years. A more accurate estimate is that it blooms once after 25 to 30 years of growth.
The golden trumpet is a flower that can bloom all year round. Apart from its beautiful appearance, this all-year flowering plant is used to kill bacterias and reduce swellings. It is scientifically known as Allamanda cathartica and is native to Brazil.
Cranesbill (Geranium), also known as true geranium or hardy geranium, is a perennial that blooms throughout the entire summer. This is not the same plant as annual geraniums (Pelargonium) that are used as bedding plants. Cranesbill will grow in full sun or partial shade.
If you don't prune hydrangeas then they can eventually resemble a tangled mass of woody stems, and the flowers will become smaller and less showy.
To rejuvenate the hydrangea, remove up to 1/3 of the older living stems down to the ground each summer. This will revitalize the plant. If necessary to control the size of the plant, cut back before late July to allow for buds to develop. Usually the plant will return immediately to its former size.
Fall is the best season to plant hydrangeas, followed by early spring. The idea is to give the shrub plenty of time to establish a healthy root system before blooming. The best time of day to plant is early morning or late afternoon.