Common Disease Problems
Alternaria Leaf Spot: Small, round reddish brown spots with white to gray centers form on the upper surface of the leaves. The lesions may encircle the stems and cause wilt. This disease is worse in warm, wet or very humid weather. Burpee Recommends: Avoid getting water on the foliage. Remove infected plant parts and do not work around wet plants. Provide plenty of air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Cercospora Leaf Blight: Small flecks which develop a yellowish halo appear on the leaves and turn brown and coalesce. They cause the leaves to wither and die. Burpee Recommends: Remove infected plants and destroy all plant debris. Rotate crops.
Damping Off: This is one of the most common problems when starting plants from seed. The seedling emerges and appears healthy; then it suddenly wilts and dies for no obvious reason. Damping off is caused by a fungus that is active when there is abundant moisture and soils and air temperatures are above 68 degrees F. Typically, this indicates that the soil is too wet or contains high amounts of nitrogen fertilizer. Burpee Recommends: Keep seedlings moist but do not overwater; avoid over-fertilizing your seedlings; thin out seedlings to avoid overcrowding; make sure the plants are getting good air circulation; if you plant in containers, thoroughly wash them in soapy water and rinse in a ten per cent bleach solution after use.
Powdery Mildew occurs on the top of the leaves in humid weather conditions. The leaves appear to have a whitish or greyish surface and may curl. Burpee Recommends: Avoid powdery mildew by providing good air circulation for the plants by good spacing and pruning. Contact your Cooperative Extension Service for fungicide recommendations.
Septoria leaf spot: Small, angular, gray-brown spots appear on leaves. Spots have defined red margins. Black fruiting bodies may be visible. Leaves will eventually become chlorotic or necrotic. Burpee Recommends: Rotate crops, avoid overhead watering. Plant to allow for good air circulation and keep weed free. Remove and destroy affected foliage.
Common Pest and Cultural Problems
Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps who feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.
Armyworm: Holes in leaves can be singular or clumped together. Leaves can become skeletonized. Egg clusters may be evident on foliage with a cottony or fuzzy appearance. Young larvae are pale green and adults are darker with a light line along the sideand pink underside. Burpee Recommends: Introduce natural enemies to the area.
Cutworms: These insects cut off the seedlings at the soil level. Burpee Recommends: Place a paper cup collar (use a coffee cup with the bottom cut out) around the base of the plant. They are usually mostly a problem with young seedlings. You can also control by handpicking and controlling weeds, where they lay their eggs.
Leafhoppers: Leafhoppers cause injury to leaves and stunt growth. They also spread disease. Burpee Recommends: Remove plant debris. Use insecticidal soaps. Consult your Cooperative Extension Service for other insecticide recommendations.
Parsley Worms: These colorful yellowish-greenish caterpillars with dotted black stripes can grow 2 inches long, will turn into black swallowtail butterflies. They feed on the foliage of parsley, carrots and dill. Burpee Recommends: Handpick. Consult your Cooperative Extension Service for other insecticide recommendations. There is no need to destroy all of these worms as they do not do a great deal of damage, and they turn into important pollinators for your garden.
Can I grow parsley indoors? Yes if you have a sunny location, you can grow parsley indoors. Parsley is also great for containers, adding interesting textures to mixed plantings.
How can I use parsley as a companion plant? Parsley can deter beetles from asparagus patches. It can also help tomatoes by deterring insects and improving the flavor.
Is parsley an annual or perennial? Parsley is a biennial. It is grown as an annual in most gardens because it is grown for the foliage which may be harvested the first year. It can tolerate frost, but tends to become more bitter the second year.
Why does my parsley taste bitter? The second year parsley will produce a flower stalk and at that time the foliage can taste bitter. You can keep the plant blooming to save the seed, but otherwise remove it at this time.
When should I add parsley to my cooking? Parsley is a delicate herb and should only be added at the end of cooking, in the last minute or two, or used as a garnish.