Why do my black-eyed Susan leaves have holes?

Why do my black-eyed Susan leaves have holes?

A. It sounds like your black-eyed Susans have a mildew or fungus. Make sure you clean the bed out thoroughly this fall and dispose of all the material. In the meantime, treat your plants with an all purpose fungicide.

How do you treat black-eyed Susan leaf spots?

Destroy spotted leaves as they appear. Finally, you can use fungicide applications to protect new growth from infection. Ortho Garden Disease Control (chlorothalonil) and copper-based fungicides such as Soap Shield are labeled to control fungal leaf spot diseases on rudbeckia.

What is eating the petals off my black-eyed Susan?

Your description is exactly right: the beetle completely consumes the flower petals, leaving just a deformed knob. I don’t think the beetle has a common name. I call mine “Susie beetles”. Spinosad is considered an organic insecticide and it will kill the beetles handily.

What bugs like black-eyed Susans?

Jagged ambush bugs also may lie in wait for bees, flies, aphids and other soft-bodied insects that come to drink nectar at these plants. In addition to these direct predators, black-eyed susans also attract parasitic insects like blister beetles, which lay their eggs on the flowers.

How do you get rid of black-eyed Susan bugs?

A strong spray of water will dislodge aphids from plants, though serious infestations can be treated with neem oil or insecticidal soap. Goldenglow sawfly is a more serious pest, whose striped gray larvae can completely strip leaves from plants. Sevin or the insecticides diazinon and malathion can be used for control.

How much water do black-eyed Susans need?

Black-eyed Susans do not need much extra water once they’re comfy and established in the garden. You do need to water them when you first plant them, though, to help the plants grow new roots and settle in. Water well whenever the top inch of soil around the plants is dry.

How often should I water black-eyed Susans?

Water well whenever the top inch of soil around the plants is dry. (A good rule of thumb: If you see the leaves drooping, the plant needs water.) Keep in mind, though, that over-watering will cause more problems with black-eyed Susans than under-watering.

How do I keep bugs off my black eyed Susans?

What is eating my Rudbeckia leaves?

Whitefly is an indication of poor ventilation and airflow. It usually happens if planting is very close, but won’t really cause any longterm problem. The small slugs and snails often do more damage than the bigger ones. Just be aware that these pelltes need using very sparingly.

What is eating my rudbeckia leaves?

When Should black-eyed Susans be cut back?

Cut back the the entire black-eyed Susan plant after the first fall frost kills off any remaining flowers. In fall, you can cut this perennial back to 2 inches above the soil line if the plant is diseased or you consider the dead stems unattractive.

Should you deadhead black-eyed Susans?

Deadheading Black Eyed Susan flowers is not necessary but can prolong the blooming period and prevent the plants from seeding all over your landscape. There are about twenty-five native species of Rudbeckia blanketing fields and meadows across North America.

What eats holes in black-eyed Susan leaves?

As with many other types of garden plants and flowering perennials, aphids are the primary insect pest of black-eyed Susans.

What is killing my Rudbeckia?

Powdery mildew and downy mildew, both fungal diseases, attack rudbeckia plants.

Should you cut down black-eyed Susans in the fall?

How do I keep bugs off my black-eyed Susans?