Amy Draiss
Hollyhocks are a quintessential part of any cottage garden. Grown as a biennial, hollyhock plants are a favorite of pollinators and even serve as a host to painted lady butterflies. Though established beds require relatively little care, learning when and how to start the plant is key to their success. How do you grow hollyhocks?
Quick Hollyhocks Facts
Botanical Name | Alcea spp. |
Plant Type | Biennial, short lived perennial |
Height | 5-8 feet (1.5-2.4m) |
Spread | 1-2 feet (30-60cm) |
Light | Full sun, partial sun |
Soil | Rich, moist, well draining, pH 6-7.5 |
Hardiness | USDA zones 2-10 (Not in the US? Convert your zone) |
Flowers | Summer (second year) |
Native Range | Asia and Europe |
Caring for Hollyhocks
Lighting Conditions
To look their best, hollyhocks need plenty of direct sun. Plant them in beds that receive at least 6-8 hours each day. However, take care with hollyhock sun requirements. Though they can tolerate some shade, excess shade may cause the plant to stretch or become leggy. Flowering can also be affected, resulting in the production of fewer or smaller blooms.
Temperature & Humidity
Hollyhocks perform well under a wide range of conditions. However, temperatures that are especially cool or hot may slow their growth and can affect their overall performance. Though hollyhocks can be grown in regions that experience high humidity, they may experience an increased susceptibility to disease.
Watering Needs
Routine watering through the summer helps to maintain consistent moisture in hollyhock beds. The plants should be watered from below, making certain to avoid the accidental wetting of leaves. This method, most often achieved through the use of drip irrigation or soaker hoses, helps to prevent common diseases. You can get a drip irrigation kit like this one from Amazon.
Best Fertilizing
Hollyhocks are heavy feeders. This means that they benefit greatly from routine fertilization. Feed the plants every 6-8 weeks with a well-balanced, slow-release fertilizer specifically formulated for use with ornamental plants. This organic slow-release fertilizer from Amazon is a great option.
Soil & Compost
Hollyhocks require a rich, fertile soil. Add some finished compost and other amendments at planting time, like this this organic compost blend from Home Depot. Provided their nutrient needs have been met, hollyhock plants are highly adaptable and can tolerate a wide range of soil types, including those that are alkaline or acidic.
How to Grow Hollyhocks From Seed
Before we can learn how to plant hollyhock seedlings, we’ll first need a better understanding of the plant’s needs for germination. Hollyhock seeds germinate readily and are planted in either spring or summer. Soaking seeds in warm water may help to speed germination, but it is not required. Seeds can be started indoors, in trays, but most find sowing directly into prepared beds to be the best option. You can expect hollyhock seeds to begin growing approximately 1-2 weeks from planting.
Hollyhock Support & Pruning
Hollyhocks have a long bloom period, with flowers slowly opening across each stem. Flowers can be pinched from the stem as each one fades. This helps prevent the production of seed and helps to keep the plants looking tidy.
Another key component of learning how to plant hollyhocks is support. Often, tall plants will begin to bend or lean due to the weight of flowers or weather conditions. Hollyhocks can be trellised in a variety of ways, including the use of individual stakes, cages, and/or netting. Amazon carries several trellis systems, perfect for any type of garden.
Hollyhock Care Calendar
| Header Cell - Column 0 | Spring | Summer | Fall | Winter |
|---|---|---|---|---|
Plant | ✓ | Row 0 - Cell 2 | ✓ | Row 0 - Cell 4 |
Fertilize | ✓ | ✓ | Row 1 - Cell 3 | Row 1 - Cell 4 |
Mulch | ✓ | Row 2 - Cell 2 | ✓ | ✓ |
Deadhead | Row 3 - Cell 1 | ✓ | Row 3 - Cell 3 | Row 3 - Cell 4 |
Stake Plants | ✓ | ✓ | Row 4 - Cell 3 | Row 4 - Cell 4 |
Cut Back Foliage | Row 5 - Cell 1 | Row 5 - Cell 2 | ✓ | Row 5 - Cell 4 |
Propagate | ✓ | ✓ | ✓ | Row 6 - Cell 4 |
Problems, Pests & Diseases
While beautiful, hollyhocks can be affected by a wide range of diseases. Most notable among these are powdery mildew and rust. Both result from issues related to moisture and humidity. This makes using proper watering techniques and spacing vital to their prevention. Several nuisance pests like to frequent hollyhock plants. Hollyhock weevils, specifically, feed on all parts of the plant. Japanese beetles can also be a problem, causing extensive damage to flowers and foliage.
How to Propagate Hollyhocks
Hollyhocks are best propagated by seed. The process begins when flowers are pollinated. After several weeks, the seed pods will have started to dry. Mature seeds can be harvested from the plant at this time, but be certain to do so before the pod splits open. Once open, pods can drop large numbers of seeds into garden soil. This makes the hollyhock an ideal addition to self-seeding or low-maintenance flower beds.
Hollyhock Frequently Asked Questions
Do Hollyhocks Come Back Every Year?
Most hollyhocks are biennial, producing foliage in their first season, then blooming and setting seed in the second year. Some newer varieties will flower in their first year, behaving as an annual (‘Queeny Purple’ is one example). But the lifespan is usually two years so they won’t ‘come back’ once they have flowered – other than from their seeds, so sow each season for ongoing hollyhocks.
Are Hollyhocks Toxic to Pets?
These flowers are generally non-toxic to cats, dogs and horses However, the stems and leaves could cause mild irritation if touched or chewed, prompted by a reaction to the tiny hairs (called trichomes). In some cases, ingesting large quantities may cause mild stomach problems. It's generally safe for humans to handle mature plants, but again, they can cause mild skin irritation, so it’s wise to wear gloves when handling them.
Are Hollyhocks Deer Resistant?
Unfortunately, hollyhocks are not deer resistant. Deer (and rabbits) could nibble the leaves, especially the young, tender growth. If you are living in an area where deer are more prevalent, it is wise to use physical barriers like mesh or fencing. You could also try introducing a deer repellent nearby, such as garlic-based Liquid Fence Deer and Rabbit Repellent from Amazon, or companion planting with rosemary or lavender.
How Tall do Hollyhocks Get?
As noted, you can get dwarf hollyhocks such as ‘Summer Carnival’ and ‘Majorette Mix’ hollyhock varieties, which can be used for container growing. However, most hollyhocks are typically tall, and their tall stems will require ongoing support. Dwarf hollyhocks can reach 12-36 inches (60-90cm), while traditional types have the potential to reach 5-7 feet (1.5-2.1m) and some can even reach 8 feet (2.4m) high.
Hollyhocks Quiz
How much have you learned about these statuesque, whimsical cottage garden ornamentals? Test your knowledge before you start growing…
