Alternanthera Purple Knight Grower Fact

Grower Facts
Alternanthera Purple Knight
(Alternanthera dentata)

GerminationUse a well-drained, disease-free, soilless medium with a pH of 5.5 to 6.3 and a medium initial nutrient charge (EC 0.75 mmhos/cm with a 1:2 extraction). Cover the seed lightly with coarse vermiculite. Light is beneficial for uniform germination.

Plug Production
Media:
Use a well-drained, disease-free, soilless medium with a pH of 5.5 to 6.3 and a medium initial nutrient charge (EC 0.75 mmhos/cm with a 1:2 extraction).
Sowing:Cover the seed lightly with coarse vermiculite.
Temperature
Germination: 72 to 76F (22 to 24C)
Cotyledon stage: 65 to 72F (18 to 22C)
True leaves: 65 to 70F (18 to 21C)
Hold plugs: 62 to 65F (16 to 18C)

Light
Stage 1:
Light is beneficial for uniform germination.
After germination: 1,000 to 2,500 f.c. (10,000 to 30,000 Lux).
Seedling maturity: Up to 5,000 f.c. (54,000 Lux) if temperature can be controlled.
Humidity:Maintain 95% relative humidity until cotyledons emerge.
Soil Moisture:Keep soil moisture high until radicle emergence, then reduce moisture levels after the radicle penetrates the medium. Do not allow the seedlings to wilt.
Fertilizer:At radicle emergence, apply 50 to 75 ppm N from 15-0-15. As cotyledons expand, increase to 100 to 150 ppm N.
Growth Regulators:Not needed.

Growing On to Finish

Media:Use a well-drained, disease-free, soilless medium with a pH of 5.5 to 6.5 and a medium initial nutrient charge.
TemperatureNights: 62 to 65F (16 to 18C) Days: 65 to 75F (18 to 24C)
Light:Higher light levels result in deeper purple foliage.
Irrigation:Irrigate plants before they are wilted severely to avoid damage.
Fertilizer:Feed plants weekly with 200 ppm N in a complete fertilizer.
Growth Regulators:Growth regulators are generally not needed. However, if necessary, a Bonzi spray at about 30 to 45 ppm is effective in controlling height and spread. Do not use Cycocel, as phytotoxicity will occur.
Pinching:Pinching is not needed.
Crop Scheduling:Sow to transplant (400-cell plug tray): 4 to 5 weeks Transplant to saleable 4-in. (10-cm) pot: 7 to 8 weeks

Container Size: 4 to 4.5-in.
Container Size: 6 to 6.5-in.
Container Size: Gallon
Plants Per Pot/Basket: 1
Plants Per Pot/Basket: 3
Plants Per Pot/Basket: 3
Weeks From Transplant: 7-8
Weeks From Transplant: 8-9
Weeks From Transplant: 8-9

If producing liners (72-tray), allow 6 to 7 weeks from sow to transplant, and reduce post-transplant crop time by two weeks.

Common Problems
Insects:
No serious problems.
Diseases: No serious problems.

Green Thumb Tips
Plant in full sun to light shade. Use Purple Knight alternanthera as a mid-height filler in mixed containers, or as a background plant in the garden. Space plants 12 in. (30 cm) apart in the garden. Using mulch around the plants seems to help get them established faster by keeping the soil cool and evenly moist. Feed regularly with an all-purpose fertilizer.