Alcea

( al - CEE - uh )

At-A-Glance Information

Alcea, commonly called Hollyhock or Hock Leaf, is a genus of biennial or short-lived herbaceous perennials that need partial shade in hot climates and regular water to perform well. These flowers will attract birds and butterflies to your yard. This classic garden flower hails from Asia and Europe and is best at the back of a border, where it won't block other plants. Round leaves form a 3 foot wide clump, and flowers bloom along upright stems in summer. Flowers take many different forms, and can be pink, white, rose, purple, red, creamy yellow, or apricot. These plants will self-sow, and return year after year with beautiful color. Use Hollyhock in mixed beds, borders, in pots, or along walkways.

Alcea species and Varietals

The genus Alcea includes about 80 species, and is a member of the plant family Malvaceae, making it a relative of plants like Hibiscus, Okra, Cotton, and Lavatera. The genus name Alcea is thought to be derived from the Greek word for mallow (alkaia). Hollyhock grows best in USDA hardiness zones 3-9 or Sunset growing zones 1-24. For more growing information, see the descriptions below. To find your zone, click here: Zone Map.

Alcea apterocarpa (Gulfatma)
This species is native to Turkey through Sinai, and reaches about 6 feet tall. Flowers are commonly white but can also be pink or violet. These plants naturally grow along roadsides, in fields, and on rocky slopes. Similar to, and sometimes confused with, Alcea biennis (to differentiate, the plant will need to fruit). Best in USDA growing zones 3-9.

Alcea digitata (Fingered Hollyhock, Digitate Hollyhock)
This tall Hollyhock is native to the Middle East. Flowers are pink or pale, and leaves are distinctly divided into three lobes. Individual plants reach up to 10 feet tall, and typically do not have many leaves, especially towards the tops of stems. This species does well in USDA growing zones 3-9.

Alcea heldreichii (Heldreich's Hollyhock)
This is a tall Hollyhock plant native to Turkey and southwestern areas of Europe. Its small leaves are shallowly lobed, and flowers are pink to white. These flowers are commonly found growing in disturbed soils along roadsides and in plowed fields. They can also be found in natural landscapes such as open areas in forests and on rocky slopes. Heldreich's Hollyhock does well in USDA growing zones 3-9.

Alcea rosea (Common Hollyhock, Holyoke)
This species is known as the common garden species of Hollyhock, and includes many different varieties with flower composition ranging from single to semi-double to double. They do well in USDA growing zones 3-9. This species was imported into Europe from China around the 15th century, and was given the name 'Holyoke' by herbalist and naturalist William Turner. These species will self-sow when left to their own devices, and if the hybridization allows. These plants can reach up to 8 feet tall and flower colors range from dark red to white, pink, yellow, and orange. Different flower colors seem to prefer different types of soils: red-flowered varieties prefer sandier soils, while lighter colors seem to favor more clay soils. Leaves are heart-shaped. There are many varieties cultivated in landscapes, some of which are listed below.

'Blacknight'
(Black Hollyhock)
With deep red, almost black flowers.

'Bride's Bouquet' Mix
This double-flowering mix comes in pinks and whites.

'Chater's Double Apricot'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Icicle'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Chestnut Brown'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Golden Yellow'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Maroon'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Red'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Salmon'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Scarlet O'Hara'
Six foot tall spires of 5-6 inch wide double flowers.

'Chater's Double Violet'
Six foot tall spires of 5-6 inch wide double flowers.

'Creme de Cassis'
White-edged currant-colored semi-double flowers.

'Halo Apricot'

'Halo Blush'
This variety has white flowers with red-pink centers.

'Halo Cerise'

'Henry VII Lemon'

'Henry VII Pink'

'Majorette Double White'
2.5 foot tall spire sprouts blooms the first year after seeds are planted.

'Majorette Double Yellow'

'Nigra'

'Peaches 'n Dreams'
Double flowers in a peachy color.

'Radiant Rose'

'Russian Yellow'

'Spotlight Mars Magic'
This plant produces bright red flowers throughout the summer.

'Sunshine'

'Summer Carnival Apple Blossom'
Double flowers bloom in the first year from seed plantings; biennial.

'The Watchmen'

'Queeny Purple'

Alcea rugosa (Russian Hollyhock)
This species is native to Ukraine, Crimea, southern Russia, and the Caucuses. It reaches up to 18-24 inches tall when mature and in bloom. It has spread in Wisconsin and Maryland as a garden-escapee turned wildflower; flowers are yellow, and leaves are deeply lobed (somewhat maple-leaf shaped). This species is best in USDA growing zones 3-8.

Alcea setosa (Bristly Hollyhock)
This species is native to Crete, Lebanon, Turkey, Syria, and Palestine. It goes dormant in the summertime, dying back to the ground. In wintertime, a rosette of flowers develops and a single flowering stem grows up from the center. Pink flowers are numerous and large, blooming from April through June. The best growing zones for this species are USDA hardiness zones 3-6.5 feet tall.

Alcea striata (Desert Hollyhock)
Native to Turkey though Saudi Arabia, this species reaches about 3 feet tall and has pink, white, or yellow flowers. These plants naturally grow on roadsides, in fields, in scrubby areas, and on rocky limestone slopes. Desert Hollyhock is hardy down to between 20 and 25 degrees Fahrenheit.

Caring for Alcea

Alcea, or Hollyhock, is typically grown from seed, though starts can also be purchased from a reputable nursery. Plant about 18 inches apart for best coverage and airflow. Taller varieties will need to be staked, especially if they are in a breezy area of the yard. Plant Hollyhock flowers in a space in the garden that receives full sun to partial shade. Ideally, they should be getting around 6 hours of sun every day, with some shade in the afternoon when temperatures are at their peak (typically between 2 and 3 PM). Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.0 and 8.0 (slightly acidic to slightly alkaline). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, water regularly at the base of plants during their active growing and blooming periods in spring and summertime.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing and flowering seasons. To prune Hollyhock plants, individual flowers can be deadheaded to encourage new blooms to emerge. Remove spent stems at their base using clean, sharp shears. In late winter, cut all stems back to a few inches above the ground. Hollyhock plants are generally biennial, meaning that they will produce foliage in their first year in the ground and flowers in the following year. There are some newer perennial varieties that can flower in their first year if planted the previous year in early fall. Fertile varieties will freely re-seed in the garden, creating a show of flowers for years.

Growing Alcea in Containers
Alcea can be grown in the ground or in a large, deep container. Choose a pot that is at least 12-16 inches deep and 24 inches wide to accommodate the large taproot. Choose a space for the container that receives full sun to partial shade that is sheltered from drafts and dry heat. Fill with well-draining potting mix amended with compost and perlite. Apply a layer of mulch to the top of soil to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Hollyhocks planted in containers will need more water than those grown in the ground. As a general rule of thumb, water whenever the top inch or two of soil feels dry to the touch. Taller varieties may need to be staked to remain upright. Prune to remove spent flowering stems and encourage more to bloom.

Harvesting Alcea
Alcea, or Hollyhock, plants are commonly used as cut flowers in fresh arrangements and bouquets. They add height, color, and pizzazz and are available in almost every color, including black. The best varieties to grow as cut flowers are those that are at least 18-24 inches tall. They are harvested from June through August or September when 1/3 to 1/2 of the florets on a stem are open. Harvesting at this time will extend their vase life, which is between 7 and 15 days. The best time of the day to cut flowers is in the morning, after dew has dried but before the heat of the day sets in. Harvest Hollyhock stems by cutting them at their base with sharp, clean shears. Remove lower leaves and then drop the stems into a bucket of cool water. To extend vase life even longer, dip 1-2 inches of the cut end immediately in boiling water (instead of placing them in cool water) to stop the release of sap that can block water uptake. Then, drop them in a bucket of cool water.

Propagation

Alcea is best propagated via seed. It is a biennial plant, typically producing flowers and seed pods in its second year. While Hollyhock will generally self-sow if left to their own devices,. The best way to propagate Hollyhock is by seed.

Propagating Alcea by Seed
Before trying this method, keep in mind that propagation by seed does not ensure that you will end up with the exact same plant as you harvested the seed from. To complete this propagation method, you will need to allow your Hollyhock flowers to stay on the plant long enough to come to seed, so do not completely deadhead all of your flowers. Seeds will be mature and ready to harvest in summer or fall, when the flowers have dried and are brown in color. Cut the flower heads off of your plant at this time, and take the seeds out of their pods. For pictures of the dried flowers and seeds, see the images below. The seeds are able to be stored in a cool, dark, dry place until you are ready to sow them. To grow Hollyhock from seed, follow these directions:

Gather your materials. You will need a pots, a spray bottle filled with water and potting soil.
Seeds can be sown indoors in the late spring or late summer, and then transplanted outside the following spring after the last danger of frost has passed. Prepare your pots by filling them with potting medium and watering to ensure that adequate drainage is occurring.
Place your seeds on top of the potting mix, spaced about 4- 6 inches apart. Sprinkle potting medium over the top until the seeds are covered. As the seeds are starting out, it is best to use a spray bottle to add moisture to avoid uncovering their soil topping. Keep the soil moist as the seeds develop, and keep pots in an area that receives sunlight and stays above a temperature of about 60 degrees Fahrenheit.
Continue to monitor for moisture and adequate soil covering until the seeds start to sprout, which should take about two weeks. Once the chance of frost has passed by, seedlings can be transplanted to a sunny area of the garden. Keep the soil moist as the plant develops, and enjoy watching your seedlings grow.

Hollyhock seed pods emerge green and turn brown as they dry out. A pod contains between 30 and 35 seeds.

Hollyhock seeds are small, flat, and typically black to dark grey or brown in color.

Problems and Pests

Alcea, or Hollyhock, are susceptible to developing issues with the following pests and diseases in the landscape.

Rust
Leaf Spot
Anthracnose
Slugs and Snails
Spider Mites
Japanese Beetles

For more information on these pests and diseases, including how to treat and prevent them, consult the following pages:

Pests & Pest Management

Plant Issues

Gallery

Hollyhock can be planted in areas that seem too narrow for such plants, as they have a deep taproot.

Hollyhock look great when planted amongst other 'cottage' garden plants.

Some Hollyhock varietals are double-bloomers.

There is a single species of Hollyhock native to the Americas, though it is a member of a different species entirely, Iliamna rivularis (Streambank Wild Hollyhock).