How to Grow and Care for Hollyhocks (Alcea rosea)

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Alcea rosea is commonly known as hollyhocks and are lovely flowering plants belonging to the genus Alcea. They are part of the Malvaceae family, which also contains Mallows and Hibiscus, and are classified as biennials, or short-lived perennials. However, they readily self-seed so they can persist for years in the garden. 

Hollyhocks are hugely popular plants and are garden favorites. They have long, straight stems bearing delightful flowers that bloom for a long period over the summer and fall. Grow them in beds and borders of cottage-style gardens, along with peonies and foxgloves for a lovely display!

History

A. rosea is thought to have originated in China, India, and Pakistan. However, the origins of the common name “hollyhock” are debated. Some say it is derived from the word holy, referring to the Holy Land (Palestine) where the first specimens to have been introduced to the U.K. came from, and the Anglo-Saxon word “hoc”.

The genus name Alcea comes from the Greek word “altho”, meaning to heal. This is in reference to the medicinal properties hollyhocks possess. It should be noted that hollyhocks may be listed under the name Althaea in some nurseries. The specific epithet rosea means pink. 

These lovely plants have a long-standing history, Thomas Jefferson grew them in his Monticello home, with an entry in his garden diary in 1782 depicting a calendar of their blooming times. There are hollyhocks still growing today in the Monticello gardens which could very well be descended from those grown by the former U.S. president himself!

Hollyhock flowers can come in either single or double form and can be white, pink, red, purple, yellow, or orange. Single varieties are attractive to pollinators such as bees, butterflies, and even hummingbirds! So these are great candidates for pollinator gardens!

Plant Facts

Scientific nameAlcea rosea
Common namesHollyhocks
GenusAlcea
FamilyMalvaceae
Height1 ft. 8 in. – 8 ft. 0 in.
Width1 ft. 0 in. – 2 ft. 0 in.
USDA Plant Hardiness Zone2-10
OriginChina, India, Pakistan
Flower colorsPink, White, Red, Orange, Yellow, Purple, Brown
Blooming seasonSpring, Summer, Fall
Plant/Flower special featuresShowy blooms borne on upright stems

How to Plant Hollyhocks

Hollyhocks plants and seedlings growing in pots can be planted at any time of the year, however, they perform best when planted during the spring or fall. Make sure to choose a site that isn’t too exposed to the wind. If there is no avoiding the windy conditions, stake them to prevent them from falling over.

hollyhock flowers

Grow Hollyhocks in Beds

If purchasing plug plants from a nursery or online, they will do best if transplanted to a 4-inch container first to allow healthy root establishment, before being planted outside.

When planting, gently tease the roots out of the container and plant them in a large enough hole, just below the surface of the soil line. Space them at least 24 inches apart. A hardening-off period is recommended before planting them outside.

Growing Hollyhock Flowers in Containers

Due to their height, growing hollyhocks in containers is not always practical. However, the introduction of dwarf varieties has made planting these delightful flowers in pots more feasible. Make sure to place the plants in an area where they will receive enough sunlight.

Choose a large container with sufficient drainage, and fill it with a mixture of soilless potting mix and well-rotted manure or garden compost. Plant the hollyhocks as you would do in beds. Container plants will require more frequent watering and fertilization with liquid fertilizer as per packet instructions.

How to Propagate Hollyhocks

Hollyhock flowers regularly self-seed in the garden or seed packets can easily be purchased in nurseries or online. However, bear in mind that hybrids and cultivars are not always true to seed. 

Sow hollyhock seeds in April/May either in a greenhouse or indoors. Alternatively, sow the seeds in autumn and overwinter new plants in a cold frame or cool greenhouse. They germinate more successfully in temperatures of 61-70°F and will germinate quickest in a propagator, however, they can also be sown in a tray with a lid and placed on a windowsill. Sow them in moist, sterile, seed compost, 6-8mm deep. 

Once the hollyhock seedlings have emerged, wait until the first set of true leaves are present before pricking them out and transferring them to a larger pot (3.5 inches). Leggy seedlings may need to be planted a little deeper (just below the first set of true leaves).

For directly sown seeds, sow them in their intended spot in May/June. 

hollyhock plants

Care and Maintenance 

Here are some tips for growing Hollyhocks:

Soil

Hollyhocks aren’t too particular about soil type but will produce the biggest flower spikes when grown in fertile, well-drained soils. 

Water

They require regular watering as seedlings and young plants to help their roots become established. In the first few months, ensure that the top 6 inches of soil remain moist but not overly wet. 

Once plants have become firmly established, they will only require watering during particularly long hot and dry periods.

Fertilizer

When grown in good quality soils, hollyhocks will not require any additional feeding. However, improving the soil by mixing in 4 inches of well-rotted compost before planting is recommended.  

Sunlight

Hollyhocks prefer full sun conditions, however, they can tolerate a little light shade.

Temperature and Humidity

They are hardy in USDA zones 2-10 so can be grown under a wide range of conditions.

Pest and diseases

Watch out for slugs and caterpillars on young plants. Occasionally they can be affected by flea beetles which may cause extensive leaf damage.

Hollyhocks are susceptible to hollyhock rust disease, which appears as orange-brown spots on the foliage. Prune infected plants regularly throughout the summer to remove any infected leaves. Every few years replace them to prevent a build-up of the disease. Make sure to remove any infected plant material to prevent a transfer of rust spores. 

Pruning

These plants readily self-seed so when flowers have begun to fade it is recommended to deadhead them by cutting the flower spike fully to the ground. Otherwise, wait until the seed pods are brown and splitting to collect the seeds before cutting down the spike. 

Throughout the flowering season, if plants are affected by rust disease, continuously cut away and discard infected leaves. 

Before winter, cut away any dead leaves, and discard any plants showing signs of rust disease. 

Uses of Hollyhocks

Hollyhock flowers are extremely popular as ornamentals in the garden and are highly recommended for cottage-style gardens due to their whimsy blooms. Their height lends them to border planting or to bring dimension to flower beds. 

Other than their beauty in the garden, these plants have medicinal, cosmetic, and culinary uses, as well as playing a huge role in the fabric dye industry. In traditional medicine, hollyhocks have been used as an anti-inflammatory, an astringent, a diuretic, and more! In fact, in some cultures, a decoction prepared with milk is given to pregnant women to ease labor. 

When incorporated into a lotion, hollyhocks have been known to soothe skin inflammation, rashes, and boils. Their root extract when applied with water is also a remedy to reduce dandruff. Their young leaves are a potherb, whereas their flowers and buds can be enjoyed in salads, or as cake decorations. Hollyhock stems, pollen, and leaves may be irritants, so always take care and seek the advice of a professional before any consumption or application.

Common Varieties and Cultivars

There are many beautiful varieties and cultivars of hollyhocks, here are a few of the most popular:

  • Black Knight – this hollyhock plant may grow as tall as 6 feet, with 4-inch blooms. Flowers are dark maroon to almost black, with bright yellow throats.
  • Chater’s Double Salmon – A fully double hollyhock flower, Chater’s Double Salmon has large, extremely ruffled flowers. Blooms are salmon pink and would look particularly at home in a cottage-style garden paired with other light-colored flowers.
  • Halo Blush – growing between 5 and 6 feet tall, Halo Blush is a wonderful plant that would suit any cottage-style garden! Flowers are white gradually fading to deep pink, with soft yellow throats.
  • Halo Lavender – Halo Lavender has lovely blooms that are a rich, deep purple, fading to a deep pink throat and white central eye. They grow between 5 and 6 feet high, making them wonderful specimens for tall borders, or next to fences! This variety has some resistance to hollyhock rust disease.
  • Peaches ‘n Dreams – this is a lovely double variety, with highly ruffled petals, Blooms are a peach cream color, often with a hint of soft pink. Plants will grow up to 6 feet high.

Conclusion

Hollyhocks, also known as Alcea rosea, are beautiful plants that are a part of the Malvaceae family! They are hardy to USDA zones 2-10 and are considered as either biennials or short-lived perennials.

They are native to China, India, and Pakistan, but are grown worldwide and are hugely popular. Former U.S. President Thomas Jefferson himself used to grow them in his Monticello home! Hollyhock plants have a wide range of uses outside of being grown as ornamentals, including medicinal properties, as herbs and decoration in cooking, cosmetics, as well as for fabric dyes.

These flowers have many wonderful cultivars and come in either single or double varieties and a range of colors including white, red, pink, orange, yellow, and purple. Their single blooms are great for attracting bees and butterflies into the garden, making them ideal in pollinator or cottage-style gardens!

Up next: Hollyhock Flower Meaning and Symbolism

*References

Reference list:

Shehzad et al. (2020), “Medicinal Plants of South Asia”,

https://www.sciencedirect.com/science/article/pii/B978008102659500029X

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