Hollyhocks - How to Grow and Use as Cut Flowers
If your heart desires a classic cottage garden, then hollyhocks are an essential. Tall spikes with numerous flowers bloom from mid-summer in a large variety of colours adding drama and height to the back of the garden.
Hollyhocks will grow under Black Walnut trees; they are tolerant of the toxic juglone that is emitted through the trees' roots.
Hollyhocks are available as biennial (Alcea rosea) and perennial (Alcea ficifolia).
Alcea rosea biennial hollyhocks. This means they grow and establish in the first year and flower the second year and normally die afterwards. However, they will set seeds.
Alcea ficifolia is a lesser known hollyhock species native to Siberia. It is commonly known as the 'Antwerp' or 'Fig-leaved Hollyhock' due to its attractive fig shaped leaves which are resistant against rust.
Seeds sown in autumn will flower in the first year.
How to Grow Hollyhocks
Hollyhocks prefer a sunny position with compost rich well drained soil. These plants quickly form a dense, well-branched plant. When in flower the plant can reach 2m in height, so protect from strong winds or stalking maybe required.
Using Hollyhocks as Cut Flowers
Hollyhocks are excellent cut flowers but they must be conditioned correctly. Hollyhocks have hollow stems which need to be filled with room temperature water immediately after being harvested. Plug the stem with cotton wool. To eliminate small air bubbles, pierce the stem with a pin just below the flower head. If flowers stems are recut, you will need to repeat this process. Let stand over night before using.
The biggest problem with Hollyhocks is rust. To prevent this allow good air flow between the plants, water the ground and not the foliage (mulch will assist in reducing the need to water) and remove any disease leaves immediately. Treat rust at the first sign of it on your plants. You can purchase liquid copper fungicide or you can make your own spray with aspirin. Dissolve two uncoated aspirin in one litre of water. Once dissolved, spray on the plants in the early spring, including the undersides of the leaves.