Black-Eyed Susan (Rudbeckia hirta)-Hort Answers - University of Illinois Extension
University of Illinois Extension

University of Illinois Extension

Hort Answers

Annual

Black-Eyed Susan
Rudbeckia hirta

<em>Rubbeckia hirta</em>
Rubbeckia hirta
 
Features
Large daisy-like flowers on compact plants. Good for the cut flower garden. 
 
Culture
Full sun in well-drained moist soil 
 
Cultivars

'Indian Summer' 2-3 feet tall, large yellow flowers with chocolate centers

'Maya' 18-24 inches tall, dwarf, compact, yellow flowers

'Prarie Sun' 3 feet tall, yellow flowers with light green center

'Spot Light' 6-12 inches tall, yellow flowers with chocolate center

'Irish Eyes' 18-24 inches tall, yellow flowers with green centers

'Cherokee sunset' 18-24 inches tall, double yellow flowers with red centers

'Toto' 6-12 inches tall, yellow flowers, dwarf

 
 
Mature Height
18-36 Inches
 
Size
Medium
 
 
Annual Hardiness Type
Tender Annual
 
 
Bloom Color
Bi-color
Orange
Yellow
 
 
Bloom Season
June - October
 
Soil Conditions
Moist, Well-Drained
 
 
Exposure/Light Requirements
Full Sun
 
 
Pests and Problems

Bacterial Disease

Environmental Damage

Fungal Disease

Insect Damage


Additional pests and problems that may affect this plant:

Powdery mildew, rust, xanthomonas, aphids
 
Additional Notes
Very colorful display of daisy-like flowers. This rudbeckia tends to decline when the weather gets hot and humid. These rudbeckia (R. hirta) are not considered perennials in northern gardens. Treat them as annuals. Attracts butterflies. Good cut flower.

 

 
Related Resources
Home, Yard & Garden Pest Guide
Illinois Commercial Landscape and Turfgrass Pest Management Handbook
U of IL - Distance Diagnosis through Digital Imaging
U of IL - Plant Clinic