Hollyhock Rust: A Guide for Young Gardeners
What is Hollyhock Rust?
Hollyhock rust is a disease that affects hollyhocks, a type of flowering plant. It is caused by a fungus called Puccinia heterospora. Hollyhock rust starts as small, yellow spots on the leaves. As the disease progresses, the spots grow larger and turn reddish-brown. Pustules, or small bumps, may also form on the undersides of the leaves.
Hollyhock rust can disfigure the plant, causing the leaves to die and drop off. In severe cases, the stems may also develop spots. Although the plant may not die, severe disfigurement can make it unsightly.
How Does Hollyhock Rust Spread?
Hollyhock rust spreads through spores, which are tiny reproductive cells produced by the fungus. Spores can be carried by wind, rain, or insects. They can also survive in soil and plant debris.
Hollyhock rust only spreads to other members of the hollyhock family, such as mallow weeds. It does not affect most other garden plants.
How to Prevent Hollyhock Rust
There are several things you can do to prevent hollyhock rust:
- Choose resistant varieties: Some varieties of hollyhocks are more resistant to rust than others. When selecting plants, look for varieties that are labeled “rust-resistant.”
- Keep your plants healthy: Healthy plants are less likely to develop rust. Make sure your hollyhocks are getting enough sunlight, water, and nutrients.
- Avoid overhead watering: Watering the leaves of your hollyhocks can create a moist environment that is ideal for the growth of rust fungus. Instead, water the soil around the base of the plants.
- Clean up plant debris: Remove any fallen leaves or other plant debris from around your hollyhocks. This will help to reduce the number of spores that are available to infect your plants.
- Control weeds: Mallow weeds are a host reservoir for hollyhock rust. Keep your garden weed-free to reduce the risk of infection.
How to Treat Hollyhock Rust
If your hollyhocks do develop rust, there are several things you can do to treat it:
- Remove infected leaves: Pick off any leaves that are showing signs of rust. Be sure to dispose of the leaves in a sealed plastic bag to prevent the spores from spreading.
- Apply a fungicide: There are several fungicides that are effective against hollyhock rust. Follow the instructions on the product label carefully.
- Improve air circulation: Good air circulation can help to prevent the spread of rust fungus. Make sure your hollyhocks are planted in a well-ventilated area.
- Burn or bury infected plants: At the end of the season, cut down any hollyhocks that have been infected with rust. Burn or bury the plants to destroy the spores.
Additional Tips for Controlling Hollyhock Rust
- Rotate your hollyhocks: Do not plant hollyhocks in the same location year after year. This will help to reduce the buildup of spores in the soil.
- Use a soaker hose: When watering your hollyhocks, use a soaker hose to deliver water directly to the soil. This will help to prevent the leaves from getting wet, which can promote the growth of rust fungus.
- Deadhead your hollyhocks: Deadheading your hollyhocks, or removing the spent flowers, will help to prevent the plant from putting energy into seed production. This will allow the plant to focus on producing healthy new growth.
By following these tips, you can help to prevent and control hollyhock rust and keep your hollyhocks healthy and beautiful.