Top 7 Biennial Flowers for the Garden

Biennials live for just two years, and flower only in their second year. During their first season, they focus on growing lush foliage and strong roots. The real show starts in their second year when your patience is paid off with a razzle-dazzle of flowers. Then they die. Fortunately, however, biennials very often reseed themselves for an even bigger show in future years. Some are so reliable, they are mistaken for perennials which can live for many years.

  • 01 of 07

    Canterbury Bells (Campanula medium)

    Canterbury Bells

    Sundar M/ Flickr / CC By 2.0 

    Most of the bellflowers are perennial but not Canterbury Bells. This quintessential English cottage flower has long racemes of boxy bell-shaped flowers in vivid blue and soft pink, lilac, and white. These are mid-season bloomers that grow from 1–3 feet tall and require full sunlight.

  • 02 of 07

    Forget-Me-Not (Myosotis)

    Forget-me-not (Myosotis)

    bereflex / stock.xchng

    These bright blue flowers are one of the hallmarks of spring and one of the best biennial self-sowers. If you find they are taking over, simply deadhead or remove some plants before they go to seed. Forget-me-nots prefer full sun and moist soil. They make a great cover for the fading foliage of spring bulbs.

  • 03 of 07

    Foxglove (Digitalis)

    Purple foxglove
    Terje Håheim / Getty Images

    There is a perennial foxglove, but most foxgloves are biennial. The plants are fairly large, even in their first year, with long, rough, but not unattractive, leaves. Depending on the variety, the flower stalks can reach up to 5 feet tall, with the dangling trumpet-shaped flowers that attract all kinds of bees, butterflies, and hummingbirds to your garden. Flowers come in yellow, pink, and purple, with speckled throats. Foxglove requires full sun to partial shade.

  • 04 of 07

    Hollyhock (Alcea rosea)

    Hollyhocks (Alcea rosea) growing alongside allotment
    Mark Bolton / Getty Images

    If you’re looking for something tall and eye-catching, you can’t go wrong with hollyhock. Topping out at more than six feet tall, they were used to disguise outhouses—in fact, there is still an heirloom available called Outhouse Hollyhock. With double or single flowers in yellow, red, pink, purple, and white, there’s a hollyhock for every garden. Plant hollyhocks in a large cluster in full sunlight, so the tall stems can help support each other. Expect blooms (and butterflies) from July to September.

    Continue to 5 of 7 below.
  • 05 of 07

    Honesty (Lunaria annua)

    Flowering Three-horned Stock -Matthiola tricuspidata-, Dilek National Park, Kusadasi, Aydin province, Aegean region, Turkey
    Martin Siepmann / Getty Images

    Butterflies and children love this plant. The mid-season clusters of purple flowers are lovely, but it’s the “silver dollar” seed pod that makes these plants so charming and give it its common name, the Money Plant. The seed pods can be easily be dried and preserved. Honesty grows to between two and three feet tall in partial shade and moist soil.

  • 06 of 07

    Stock (Matthiola)

    Stock (Matthiola)

    Patrick J. Alexander, hosted by the USDA-NRCS PLANTS Database

    Many flowers promise scent, but stock really delivers, with a strong, spicy fragrance. These are early bloomers that prefer the cool temperatures of spring along with full sunlight. There’s a wide choice of colors, including white, pink, lavender, yellow, and deep reds. The plants don’t grow particularly tall and can make nice edging plants. There are dwarf varieties that reach less than one foot and others that approach three feet. Popular varieties include Matthiola longipetala and M. Incana, while Matthiola Bicornis releases its scent at night.

  • 07 of 07

    Sweet William (Dianthus barbatus)

    Sweet William (Dianthus barbatus)

    sumeja / Stock.xchng

    The spicy clove scent will tell you that Sweet William is in the carnation family. This is a tidy plant, with grass-like, low-growing foliage and flattened dome flower heads. The velvety flowers come in reds, pinks, purples, and bi-colors. If you keep them deadheaded, they will repeat bloom through late spring into summer. Sweet William needs full sun and will attract butterflies to your garden.

Keep Your Biennials Coming Back

If you want blooms every year, rather than every second year, start another seedling or planting of biennials during the first planting’s second year. For best results, follow this schedule:

  • Year 1: Start seeds or seedlings
  • Year 2: Last year’s biennials will bloom, then go to seed. Start more seeds or seedlings to bloom next year.
  • Year 3: Seeds from 1st planting of biennials will sprout and just grow foliage. The second planting will bloom, then go to seed.
  • Year 4: From here on, some plants will be going to seed and other flowering every year.