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First-Year-Flowering Scheduling Tool

Penstemon barbatus Rock Candy®
North: grown outdoor flowering window weeks 24-37
South: grown outdoor flowering window weeks 19-40
Spring-early summer programs
Week color desired
URC stick week  
Liner ready week  
Liner transplant week  
Late summer - fall programs
Week color desired
URC stick week  
Liner ready week  
Liner transplant week  
*Plantings after week 25 finish faster
Penstemon barbatus Rock Candy® Blue
Penstemon barbatus Rock Candy® Light Pink
Penstemon barbatus Rock Candy® Pink
Penstemon barbatus Rock Candy® Ruby
Suggested Container Size.
Container: 2.5 qt (1 ppp)
Propagation Guide
Media EC/pH: EC 0.75-0.80 mmhos/pH 5.8-6.2
Soil Temperature: 70-72°F (21-22°C)
Rooting Hormone: 500 ppm IBA
Mist: Moderate to high for first 24 hours, then reduce to low.
Fertilization: 50-75 ppm N
Pinching: Recommended.
Transplanting: Liner transplant week
Comments: Use low mist settings; do not oversaturate rooting media. Root zone temperatures of 70°F (21°C).
Finishing Guide
Media pH: 5.8-6.2
Temperature: Nights: 55 to 70°F (13 to 21°C) Days: 60 to 80°F (15 to 27°C)
Light Level (fc): 3,000 to 5,000
Vernalization: No
Watering: Allow media to dry moderately between watering.
Fertilization: Use a balanced fertilizer at a rate of 150 to 175 ppm N.
Pinch After Transplant: Yes
Plant Growth Regulators: PGRs generally not needed
Pests and Fungal Diseases: Spider mites, thrips. Watch for INSV/TSWV.