Common Disease Problems
Anthracnose: Small water soaked spots on leaves and stems. Burpee Recommends: Avoid planting in the same location in the future, planting in containers can help. Prune plants to the ground in the fall.
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.
Mint Rust: Small, whitish, slightly raised spots that turn reddish orange or brown. This occurs on the underside of the leaves. Burpee Recommends: Avoid overhead irrigation systems. Water early so the leaves have the whole day to dry out. Do not plant members of the mint family in the same location.
Powdery Mildew: This fungus disease 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.
Verticillium wilt: Yellows begin turning yellow starting at the margin. Eventually, leaves will curl and die. Burpee Recommends: Rotate plantings, remove infected plants, do not over fertilize.
Common Pest and Cultural Problems
Aphids: Greenish, red, black or peach colored sucking insects that 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.
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.
Leafminers: These insects bore just under the leaf surface causing irregular serpentine lines. The larvae are yellow cylindrical maggots and the adults are small black and yellow flies. They do not usually kill plants, but disfigure the foliage. Burpee Recommends: Remove affected foliage.
Thrips: Cause leaves to be distorted, cause stippling and may appear silvery. Speckled with black feces. Adults pale yellow to light brown. Can transmit viruses. Burpee Recommends: Use reflective mulches. Contact your local Disease Extension Agency.
Spider Mites: These tiny spider-like pests are about the size of a grain of pepper. They may be red, black, brown or yellow. They suck on the plant juices removing chlorophyll and injecting toxins which cause white dots on the foliage. There is often webbing visible on the plant. They cause the foliage to turn yellow and become dry and stippled. They multiply quickly and thrive in dry conditions. Burpee Recommends: Spider mites may be controlled with a forceful spray every other day. Try hot pepper wax or insecticidal soap. Check with your Cooperative Extension Service for miticide recommendations.
What is the difference between Italian and Greek Oregano? Both are from the Mediterranean and both are used in Greek and Italian dishes. Greek has a spicier flavor.
Is oregano related to marjoram? Yes, they are the same genus. Marjoram has a sweeter and milder flavor.
Is oregano better fresh or dried? Oregano tends to have better flavor when used dried.
When should I add oregano when cooking? Add oregano twenty minutes before the dish is ready. It is not a delicate herb.
Can I grow oregano indoors? Yes, oregano is good to grow indoors.