Hollyhocks: How to Plant, Grow, and Care for Maximum Blooms

I’ve got fond memories dating back to childhood of my grandparents growing hollyhocks in their cottage garden. These classic blooms (the ‘Outhouse’ staple in Victorian times) can make a real statement when carefully incorporated into your garden design. In this guide, I’ll run through my go-to tips on growing and caring for hollyhocks including planting, ideal soil types, watering schedules, fertilizing, seasonal maintenance, and more.  

Further reading: your complete guide to the various types of biennial flowers and plants to grow in your garden.

Growing From Seed Vs Transplanting

Some gardeners swear by growing hollyhocks from seed, while others prefer transplanting seedlings. Both methods have their pros and cons.

Growing From Seed

• Seeds can be planted outdoors in the fall or indoors in early spring.
• Fall planting allows seeds to lie dormant and sprout in the spring.
• Early spring planting indoors requires transferring seedlings outdoors after the frost.

Transplanting

• It’s ideal when you purchase young plants from a nursery.
• Ensure the garden spot has good drainage and full sun.
• Space plants 18-24 inches apart to avoid rust fungal disease.

Personal Preference

Deciding between seeds and transplants comes down to your personal preference and gardening style. Those who enjoy nurturing plants from the very beginning might opt for seeds. Gardeners looking for quicker blooms or avoiding the hassle of indoor seed starting are best to opt for transplanting.

How to Plant

Setting your hollyhocks up for success involves finding the perfect spot, timing your planting correctly, and following the best techniques to help the flowers thrive from the start.

Best Locations

Hollyhocks grow best in areas that get full sunlight. They should be planted where they can soak up at least six hours of full sun each day.

I also recommend finding a spot that’s a little sheltered from strong winds. Near a garden wall or fence is typically ideal.

The soil should be rich and well-draining. Try to avoid areas where water tends to pool after it rains. If the soil is heavy clay or sandy, consider amending it with compost to create a more hospitable environment.

Planting Times

Plant hollyhock seeds in the late spring or early summer. Timing is crucial because if planted too early, the seeds might not germinate in colder soil. They usually need temperatures above 50°F (10°C).

In regions where winters are mild, hollyhocks can also be planted in the fall enabling them to establish roots before the next growing season.

How to Plant

Start by preparing the soil. Dig holes that are about twice the width and depth of the root system of each seedling. Space the seeds or seedlings about 2 feet apart to give each plant enough room to grow and spread.

Place the seedling in the hole, gently pressing the soil back around the roots. Make sure the top of the root system is level with, or just above, the soil surface. Water deeply right after planting to help settle the soil around the roots.

If planting from seeds, sprinkle them on the soil surface and lightly cover them with a thin layer of soil. Water gently to avoid washing away the seeds. Regular watering is crucial during the first few weeks.

Hollyhock Flower Care

Hollyhocks are generally low-maintenance biennials but there a few basic plant care steps to follow to get the best blooms.

Soil

• Hollyhocks thrive in well-draining, organic-rich soil. This helps prevent waterlogging, which can cause root rot. Aim for a soil pH between 6.0 and 8.0.
• Before planting, loosen the soil and mix in compost to improve fertility. Avoid heavy clay soils as they can retain too much water.

Sunlight

• Hollyhocks love sun! They need full sun to grow strong and produce lots of flowers. Aim for at least six hours of direct sunlight each day.
• While they can tolerate a bit of shade, too much shade will result in fewer blooms and lanky growth.

Temperature Tolerances

• Hollyhocks grow best in mild to warm climates but can withstand cold winters with proper care.
• For areas with harsh winters, protect the plants with mulching. In very hot climates, some afternoon shade can prevent the leaves from scorching.

Watering

• Watering consistently is key. Keep the soil evenly moist, but not waterlogged.
• It’s best to water at the base of the plants to reduce the risk of leaf diseases, especially rust, a common issue with hollyhocks.

Fertilizing

• For healthy growth, fertilize hollyhocks once or twice a season. Use a balanced 10-10-10 fertilizer or a soluble one.

Pruning

• Pruning isn’t a must, but it helps them look tidy. Remove spent flowers to encourage more blooms and cut back dead or diseased stems promptly.
• At the end of the growing season, prune the plants down to ground level to prepare for overwintering and to control any pest problems.

Pest Control

• Hollyhocks can attract pests like aphids and Japanese beetles. Regular inspection helps catch and address infestations early. Handpick the insects or use a gentle insecticidal soap.
• Rust, a fungal disease, is another nuisance. I find the best mitigation methods are to water at the base of the plant and ensure good air circulation by spacing plants properly.

End Of Season

• As the season winds down, it’s time to manage the last blooms and dead material. Deadhead remaining flowers and remove any fallen leaves to reduce disease risk.
• Collect seeds if you wish to replant next year. This cleanup helps the garden look neat and prepares it for winter.

Overwinter Care

• In cold climates, cut them to the ground after the first frost. Mulch around the plants to protect the roots from freezing.
• In milder climates, a light mulch will suffice. Come spring, remove the mulch and watch your hollyhocks spring back to life, ready for another season.

Recommended Types

Hollyhocks come in a variety of colors and types. Each has its own charm and fits different garden styles. Here are some of my favorites:

• ‘Nigra’ (Alcea rosea) – Known for its near-black, deep purple blooms, this striking variety adds a dramatic touch to any garden.
• ‘Indian Spring’ (Alcea rosea) – A compact variety with single and semi-double blooms in pastel shades of pink, white, and yellow, perfect for smaller spaces.
• ‘Chater’s Double’ (Alcea rosea) – Famous for its large, fully double blooms in a range of colors, including pink, red, yellow, and white. These tall, stately plants add vertical interest.
• ‘Halo Mixed’ (Alcea rosea) – This variety features a halo-like dark center surrounded by vibrant colored petals, adding eye-catching contrast to your garden.
• ‘Majorette’ (Alcea rosea) – A dwarf variety, reaching 2-3 feet tall, with semi-double blooms in colors like red, pink, yellow, and white, ideal for containers or smaller spaces.
• ‘Creme de Cassis’ (Alcea rosea) – Known for its stunning bicolor flowers, with deep purple centers fading to lighter outer petals, adding a unique splash of color.
• ‘Peaches ‘n Dreams’ (Alcea rosea) – A lovely variety with large, double peach-colored blooms, perfect for cottage-style gardens.
• ‘Russian Hollyhock’ (Alcea rugosa) – A hardy, drought-tolerant species with pale yellow single flowers, often blooming later in the season, adding variety to traditional hollyhocks.
• ‘Bristly Hollyhock’ (Alcea setosa) – Known for its bristly stems and bright pink or purple flowers, this variety is more resistant to pests and diseases than some other hollyhocks.

Propagating

Propagating hollyhocks can be a fun process. There are three primary methods to consider – by seed, division or root cuttings:

1. Propagating by Seed:

Hollyhocks are most commonly propagated by seeds, and they are known for easily self-seeding in the garden.

• Harvesting Seeds: After flowering, allow the seed pods to dry on the plant. Once they are brown and crispy, collect the seeds.
• Sowing Seeds: Hollyhocks can be sown directly outdoors in late summer or early fall. Alternatively, sow seeds indoors 6-8 weeks before the last frost in early spring.
• Planting Depth: Plant the seeds about ¼ inch deep in well-drained soil. Keep the soil moist until germination, which takes about 10-14 days.

2. Propagating by Division:

Though less common, you can propagate hollyhocks by division, especially for perennial varieties or plants that have reseeded themselves.

• Timing: Early spring is the best time to divide hollyhocks, just as new growth begins.
• How to Divide: Carefully dig up the plant, ensuring you get as much of the root system as possible. Divide the clumps by gently pulling them apart or cutting with a sharp knife, making sure each division has roots attached.
• Replanting: Replant the divisions immediately in well-drained soil and water thoroughly.

3. Propagating by Root Cuttings:

This method works best for perennial hollyhocks or those that behave as short-lived perennials.

• Timing: Take root cuttings in late fall or early spring.
• How to Take Cuttings: Dig around the base of the plant to expose some roots. Cut 3-4 inch sections of the thicker roots, ensuring each piece has at least one growing point.
• Planting the Cuttings: Plant the root sections horizontally, just below the surface of the soil, and keep them moist. They will sprout new shoots in the spring.

Personaly, I find propagation via seed to be the most reliable method, and hollyhocks often self-seed readily, making them easy to naturalize in your garden. 

Best Companion Plants

Hollyhock flowers thrive alongside a variety of other plants. Here are a few of my top picks:

Peonies
Peonies not only add color but also help keep the soil moist around hollyhocks. They form dense growth, shading the ground and preventing it from drying out.

Foxglove
Foxglove’s tall, tubular flowers look lovely alongside hollyhocks. Both plants love the sun and can create a stunning display when planted together.

Lupines
Lupines are another great option. Their vibrant spikes of flowers add a layer of interest.

Baby’s Breath
Baby’s breath is perfect for filling in the lower spaces around hollyhocks. Its delicate white flowers create a soft contrast to the bold hollyhock blooms.

Bee Balm
Bee balm attracts pollinators like bees and butterflies, which can help your garden thrive. Its bright colors stand out against the taller hollyhocks.

Black-Eyed Susan
These cheerful flowers bring a burst of yellow to your garden. Their medium height works well to fill in gaps around the taller hollyhocks.

Mullein
Mullein plants are tall and sturdy. They can add visual interest and pair well with the tall growth of hollyhocks.

Garden Design Tips

Hollyhocks offer a range of interesting options when incorporating into your broader garden layout:

Use Hollyhocks as Vertical Accents – They are perfect for those locations at the back of flower borders, along fences, or against walls where their height can be showcased and supported.

Create a Cottage Garden Look – These flowers are a quintessential cottage garden staple. I love to pair them with other traditional cottage flowers like foxgloves, delphiniums, and daisies.

Use as a Living Screen or Divider – Hollyhocks are ideal for screening or dividing sections of the garden. Plant them along pathways, garden edges, or between different garden rooms to create natural barriers or a soft backdrop.

Plant in Drifts or Groups – For the most impact, plant in drifts or clusters of 3-5 plants. This mass planting creates a fuller look and ensures an impressive display when they bloom.

Mix Colors for Visual Appeal – Hollyhocks come in all sorts of lovely colors, from pastel pinks to deep purples and even near-black hues. Mixing different colors in the same area can create an eye-catching display. Alternatively, planting hollyhocks in single-color groups can add a dramatic effect.

Stagger Bloom Times – To extend the blooming season, consider planting varieties that bloom at different times. This can keep your garden in flower from mid-summer to early fall.

Consider Self-Seeding – These plants are prolific self-seeders, which can be a bonus if you want them to naturalize in your garden. However, if you prefer a more controlled garden, you may want to deadhead them before they set seed to prevent too much spreading.

Common Problems And How To Deal With Them

Hollyhocks can face some common challenges from pests and bugs in my experience. Here’s how to keep them healthy and happy:

Hollyhock Rust – One of the most common issues is rust, a fungal disease that causes orange spots on leaves. Remove affected leaves immediately. Use a fungicide labeled for rust treatment. Make sure to space plants well for better air circulation.

Aphids -Aphids love hollyhocks. If you see these small bugs, spray the plants with a strong stream of water to wash them off. You can also use insecticidal soap.

Japanese Beetles – These beetles munch on leaves and flowers. Hand-pick them off the plants in the early morning when they’re sluggish. Consider using beetle traps to reduce their numbers.

Powdery Mildew – In humid conditions, you might see a white, powdery substance on the leaves. To tackle this, remove affected leaves and improve air circulation around the plants. Applying a fungicide can also help.

Poor Flowering – If your hollyhocks aren’t blooming well, they might need more sunlight. Ensure they get at least six hours of direct sun daily. Also, fertilize them with a balanced 10-10-10 fertilizer during the growing season.

Wilting – Wilting can be a sign of either overwatering or underwatering. Check the soil moisture. It should be moist but not soggy. Adjust your watering schedule accordingly.

Slugs and Snails – These pests can also damage hollyhocks. Use iron phosphate-based slug baits or create barriers with crushed eggshells around the plants.

Further Reading And Recommended Resources

There’s a lot to learn and love about perennial plants. Here are some of my favorite books and resources:

Books:

• “The Complete Garden Flower Book” by Lewis Hill and Susan Hill – A comprehensive guide covering over 600 plants, including hollyhocks, with practical growing tips and troubleshooting advice. This book is ideal for both beginners and experienced gardeners.
• “From Seed to Bloom: How to Grow over 500 Annuals, Perennials & Herbs” by Eileen Powell – This book includes detailed instructions on growing biennials from seed, including hollyhocks, along with a wide range of other flowering plants.
• “Floret Farm’s Cut Flower Garden” by Erin Benzakein – This beautifully illustrated book provides a detailed guide to growing cut flowers, including biennials like hollyhocks and sweet William. It’s a favorite among gardeners for its practical advice and inspirational photography.
• “Mastering the Art of Flower Gardening” by Matt Mattus – This book is ideal for gardeners looking for a deeper understanding of flower cultivation, including how to grow and manage biennial flowers for season-long blooms such as hollyhocks.
• “Color in Your Garden” by Penelope Hobhouse – Known for its insights into biennial planting designs and color schemes, this book is ideal for gardeners who want to add an artistic touch to their gardens.

Online Resources:

• National Gardening Association (NGA) – The NGA offers practical advice for growing and caring for biennial flowers, such as hollyhocks, with tips for planting and maintenance.

Forums and Communities

Getting advice from fellow gardeners can be incredibly useful. Websites like GardenWeb and The National Gardening Association have forums where people share their experiences and tips for growing hollyhocks.

YouTube Channels

For visual learners, channels such as Growing in the Garden offer practical video tutorials. They cover everything from planting techniques to seasonal care tips for hollyhocks.

Wrapping Up

I think hollyhocks are a brilliant addition to any cottage style garden project. I love their tall and striking blooms which add real interest alongside fences and walls. Plus, once you get them set-up, they’ll reliably re-seed and return year after year.

Quick Care Tips for Hollyhocks:

• Sunlight: Full sun
• Soil: Well-draining, rich in organic matter
• Watering: Regular, deep soakings
• Fertilizing: Once or twice per season
• Staking: Necessary if not planted against a fence or wall

Happy gardening!