Hollyhock (Alcea) Plant Profile
Care, Maintenance, Uses and Specific Cultivars of Hollyhock Plants
A strong accent plant reminiscent of heirloom gardens and cottage borders, Hollyhocks are a charming addition to any garden space. See how to cultivate the hollyhock.
Botanical and Common Name: The scientific name for Hollyhocks is Alcea rosea but used to go by the scientific name Althaea and is still seen that way in garden catalogs on occasion.
Hardiness Zones: Hollyhocks are hardy in zones 2-10.
Plant Category: Hollyhocks are herbaceous biennials or short-lived perennials.
Bloom Time and Color: Hollyhocks have large 4-5” saucer shaped flowers for up to 2 months in midsummer. They are available in a variety of colors such as yellow, red, purple, pink and white on large flower stalks up to 8’ tall.
Foliage: Rough textured leaves are large and generally attractive.
Growth Habit: Upright and slender, hollyhocks add a strong vertical interest to a garden space.
Dimensions: 5-8’ tall and only 1-2’ wide hollyhocks are upright plants.
Preferred Conditions: Hollyhocks prefer rich, well-drained soil and full sun. Light shade is tolerated but wet winter soil is not.
Maintenance: Deadheading wilted hollyhock flowers will encourage reblooming and should be done until the end of the season unless self-sown seedlings are desired. Many hollyhocks rarely require staking except in high-wind or very rainy areas.
Pests or Diseases: Hollyhocks are susceptible to rust, leaf spot, aphids and cut worms.
Propagation Methods: Hollyhocks are easy to grow from seed that can be scattered outdoors in the late spring through early fall for blooms the following August. Or plant started plants for hollyhock blooms that same year. Division is not needed as individual hollyhock plants are short lived, however self-sowing happens frequently so hollyhock clumps are often perennial in nature.
Companion Plants: Hollyhocks do well with other cottage garden plants such as Columbine (Aquilegia), Roses, Bellflowers (Campanula), and Thyme.
Seasons of Interest: Large, lobed leaves are attractive in the spring while the stately flower stalks hold interest all summer and fall.
Uses in the Garden: Perfect for planting in the back of borders, for old cottage gardens, cut flower gardens, humming bird beds or fence borders.
Other Uses: Hollyhocks are tolerant of black walnut toxins and, like Polemonium plants, can be planted near and around black walnut trees where other plants will not grow.
Varieties and Cultivars:
- Alcea rosea ‘Nigra’: One of the most beautiful and unique hollyhocks is an heirloom cultivar Thomas Jefferson grew at Montecello for its dark red, almost black, flowers. Foliage prone to disease and will likely look tattered by fall so this hollyhock is better suited for the back of a border where the foliage won’t be seen but the tall flowers will still be enjoyed.
- Alcea rosea ‘Charter’s Double’: This hollyhock has large, fully double flowers are nearly pom-pom in appearance. Mixed colors.
- Alcea rosea ‘Marjorette Mix’: A dwarf form of hollyhock that grows to only 2’ tall and will bloom the first year from seed if planted in the spring. An All America Selection Winner.
- Alcea rosea ‘Queeny Purple’: Another dwarf cultivar, this hollyhock was a 2004 All-America Selection Winner and will bloom quickly from seed the first year. Only reaches 30” tall with double-flowers that are a cranberry-mauve color.
- Alcea rosea ‘Indian Spring’: A mix of rose, pink and white colored single or semi-double flowers, this hollyhock series grows about 7’ tall and combines with a wide variety of plants in a mixed border.
- Alcea rosea ‘Creme De Cassis’: Highly ornamental and eye-catching hollyhock, this cultivar produces flowers that are 3-4” large and grow 6-7’ tall. The ‘Crème de Cassis’ flowers are berry colored, semi-double blooms with cream colored petal edges and dark colored veins. Very attractive, ruffled flowers.
