Hollyhocks
Hollyhocks have an old-fashioned charm reminiscent of grandmother’s garden and old country houses. The flower colour varies greatly from variety to variety and can range from light pastel to dark purple tending towards black.
Where to grow hollyhocks
Hollyhocks come in many colours and shapes. Most hollyhocks are perennials and don’t flower until year two. Annual varieties are best suited to growing in pots, for example on a balcony or patio. They are usually not as tall and therefore take up less space.
Regardless of the variety, hollyhocks prefer a sunny location and nutrient-rich, well-drained soil. If it is too shady and moist, they risk being attacked by diseases. As some varieties can grow up to three metres tall, it’s a good idea to place it where it can lean against something and is slightly sheltered from the wind, such as a house wall or fence. Otherwise, you can use some kind of plant support once it starts to grow properly.
Sowing hollyhocks
Hollyhocks can be pre-cultivated or sown outdoors. There are a few different varieties, depending on the variety. Many varieties are annuals if you sow them indoors, but flower in year two if you sow them outdoors in late summer.
The easiest time to sow outdoors is May-August. This gives the seeds time to develop into leaf rosettes, which then overwinter and flower in year two. If you pre-cultivate, you should start early, preferably as early as February, so that the hollyhock has time to flower in year one. The risk when you push it up to flower in year one is that it will then become an annual and not come back. However, this can usually be prevented by cutting back the plant before it has gone to seed.
Sow very shallowly and cover with an extremely thin layer of soil. If you are pre-cultivating, keep the plants in a cool, bright place once they have started to germinate. Plant lighting is a great advantage in spring-winter. Harden off and plant out when the risk of frost is over.
Another option is to sow in pots during the summer. Then next spring you can place the leaf rosettes where you want them to flower in late summer. Bury them deeply and at least 40 cm apart.
Care and maintenance
The more nutrients, the taller the hollyhocks. Fertilise before planting out and preferably again during the season. Water regularly, but do not overwater – this increases the risk of infestation.
When the hollyhocks have finished flowering, usually at the end of September, you should cut back the plants to give them new life for the next season. Hollyhocks also thrive on winter cover, such as spruce branches or leaves.
Unfortunately, hollyhocks are often affected by hollyhock rust. It manifests itself as unsightly spots on the leaves and can eventually lead to poor flowering and stunted growth. If you start to see yellow spots on the leaves, you should remove them as soon as possible. Do not throw the leaves on the compost heap, but burn them or throw them in the household rubbish. To prevent disease, keep hollyhocks in an airy, slightly windy place.
Enjoy!
Hollyhocks bloom late and long, often all the way from July to September. Bees and other pollinators absolutely love hollyhocks, which provide them with plenty of pollen.
If you let the hollyhocks bloom before you cut them back, they will develop seed pods that you can harvest and use for seed in the future.
Author: Johanna Damm
Fact-checked by Erik Hoekstra
Last updated 2022-10-14