Bronze fennel is the ornamental form of common fennel — the same anise flavour as green fennel but with spectacular bronze-purple feathery foliage that looks extraordinary in the garden and in arrangements. All parts are usable: fronds as herb, seeds as spice, and pollen as a prized finishing ingredient. The tall flat-topped yellow flower heads attract beneficial insects and swallowtail butterfly larvae.
Do not plant near dill — they cross-pollinate, degrading both. Self-seeds prolifically and can become weedy; deadhead before seeds disperse if you want to control its spread. Fennel is allelopathic to many vegetables and should be kept away from the kitchen garden.
Aphids
Clusters of small soft insects on new growth and flower buds.
Knock off with a strong jet of water. Ladybirds and lacewings are natural predators. Insecticidal soap as last resort.
Powdery mildew
White or grey powdery coating on leaves — usually starting on older growth in humid conditions or when nights cool.
Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.
Damping Off
Seedlings collapse at the soil line with thin, water-soaked stems; seeds may fail to emerge or rot before sprouting.
Sow in well-draining mix, avoid overwatering, and ensure good airflow. Remove affected seedlings and let the surface dry between waterings.
Cercospora Leaf Spot
Small round spots with tan or gray centers and reddish-purple borders on leaves. Spots merge in severe cases, causing leaves to brown and die back.
Remove infected leaves and avoid overhead watering. Space plants for airflow and rotate crops. Apply a copper-based fungicide if the infection spreads.