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The Homeowners Column
Hollyhocks - a favorite summer flower
Extension Educator, Horticulture
Probably no other plant is more closely associated with summers on the farm than hollyhocks. Many a childhood memory includes a view of colorful spires of bell shaped flowers rising above the sight and smell of chicken pens and cowpies. Hollyhocks with their flowers reminiscent of ladies waiting in line for a summer cotillion have become more popular recently with the interest in cottage gardens. At 5-9 feet tall they can be used as a towering background plant in a flower border, or along a fence or wall.
The older varieties of hollyhocks are short-lived perennials that are usually treated as biennials. The first year flowering is sparse, but the second year they show their glory flowering June to late August. Although the plant may live and flower for several years, it rarely flowers as much as a new plant started from seed. Once hollyhocks are established their self seeding characteristic keeps them blooming like new each year.
Seeds may be sown now or in August to produce flowering plants next year. Many of the newer cultivars flower the first year from seed.
Hollyhocks do best in full sun; in moist but well drained areas. They appreciate fertilizer in early spring which could explain their love of manure piles.
Hollyhocks are tough plants, but they do have some insect and disease problems. Hollyhock rust is the most common and widespread disease. Rust is a fungus that first appears on the undersides of lower leaves as lemon-yellow to orange pustules that darken with age. The top of the leaf shows bright yellow to orange spots with reddish centers. Spots may quickly come together to destroy large portions of the leaf.
Good sanitation can control rust. The first rusted leaves in the spring should be picked off and destroyed. As soon as flowering is over, infected plants should be cut back to the soil line. All infected leaves and stalks should be removed and destroyed by burying in a compost pile or unused part of the garden. However be sure to let a few stalks ripen so plants can reseed.
If sanitation does not control the disease, a fungicide can be applied in spring as new growth starts. Several sprays will be necessary to keep new leaves protected against infection.
Spider mites, Japanese beetles and leaf feeding caterpillars can also plague hollyhocks. However most problems except for Japanese beetles cause the leaves to look lousy, but the flowers still look charming. Or plant hollyhocks far enough away so you don't see the leaves, or plant something in front of the hollyhocks to hide the leaves.
Newer strains of hollyhocks have fringed, ruffled or doubled petals. These include:
- 'Charter Series' double flower, wide variety of colors at 6-8 feet tall and acts more like a perennial with individual plants living longer.
- 'Marjorettte' double lacy flowers, mixture of colors at only 2 feet tall and is an annual flowering the first year from seed.
- 'Nigra' has chocolate-maroon flowers.
- 'Pinafore Mixed' single and semi-double flowers, various colors at 3-3 ½ feet tall.
- 'Summer Carnival' double blooms at 4-5 feet tall, wide color range and an early bloomer.
The many shades of pink flowers of 'Indian Summer' and 'Indian Spring' appear the first year from seed.
For attractive mini-hollyhock cousins try 'Twin Hot Pinks' lavatera and 'Zebrina' dwarf hollyhock.