Grower Facts Pentas Butterfly
(Pentas lanceolata)

Germination
Do not cover the seed. Light during germination (10 f.c./100 Lux) will improve germination uniformity and seedling quality.

Plug Production
Plug Tray Size
Butterfly pentas plugs are best produced in 392/406- cell or larger plug trays.

Sowing
Use a well-drained, disease-free seedling medium with a pH of 6.5 to 6.8 and EC about 0.75 mmhos/cm (1:2 extraction). Do not cover the seed.

Temperature
Germination: 74 to 80°F (23 to 26°C)
Cotyledon emergence: 68 to 72°F (20 to 22°C)
True leaf expansion: 65 to 68°F (18 to 20°C)
Plugs may be held at 60 to 65°F (15 to 18°C) from maturity until transplant.

Light
Light during germination (10 f.c./100 Lux) will improve germination uniformity and seedling quality. Pentas have high light requirements. Seedlings must receive higher light levels immediately after germination to avoid elongation and promote rapid growth. After germination, maintain light levels between 1,000 and 2,500 f.c. (10,000 to 30,000 Lux). As seedlings mature, light levels may be increased up to 5,000 f.c. (54,000 Lux) if temperature is controlled.

Humidity
Maintain 100% relative humidity until cotyledons emerge. Avoid keeping the flats wet. Reduce the humidity to 50% as plugs mature to control foliar diseases.

Fertilization
Fertilize with 50 ppm nitrogen from 15-0-15 or 15-5-15 as soon as radicles emerge. When cotyledons expand, increase fertilization to 50 to 75 ppm nitrogen. Use 20-10-20 with every other fertilization only if growth slows. During Stage 3, increase fertilizer to 100 to 150 ppm to promote rapid plug growth. Maintain medium EC between 1.0 and 1.5 mmhos/cm (1:2 extraction). If the pH drops below 6.0 in the soil, plants will show severe iron toxicity and growth will slow or stop. Periodic feedings with CaNO3 will help avoid pH drop.

Growth Regulators
Control plug growth first by environment, nutrition management and irrigation management (keep plants on the dry side). Minimize phosphorus fertilizer to avoid elongation of seedlings. Temperature differential (DIF) can also be used to minimize height. If necessary, Cycocel spray can be applied at 500 ppm about 5 to 6 weeks after sowing.

Growing On to Finish
Container Size
Butterfly pentas are well-suited to 4-in. (10-cm) pots up to 1 to 2-gallon containers. Use 1 plug per 4-in. (10- cm) pot, 1 to 2 plugs per 6-in. (15-cm) pot, and 2 to 3 plugs per 1 to 2-gallon container.

Media
Use a well-drained, disease-free soilless medium with a medium initial nutrient charge and a pH of 6.5 to 6.8. If the pH drops below 6.0, severe marginal burn of leaves due to iron toxicity may occur and plants will stop growing.

Temperature
Butterfly pentas benefit from warm temperatures and high light conditions. Maintain minimum night temperatures of 62 to 65°F (17 to 18°C) and minimum day temperatures of 72 to 75°F (22 to 24°C).

Light
Keep light levels as high as possible to promote compact growth. Butterfly pentas will tolerate higher temperatures than other crops.

Humidity
Maintain low relative humidity during production to reduce foliar diseases.

Water
Avoid both excess watering and drought, which will stress the plants and cause severe yellowing and necrosis.

Fertilization
Fertilize every irrigation at 150 to 250 ppm with 15-0-15 or 15-5-15; apply 20-10-20 as needed to promote leaf expansion. Maintain medium EC around 1.0 mmhos/cm (using 1:2 extraction).

Growth Regulators
Effective height control of Butterfly pentas can be accomplished with environmental manipulation. Height can also be controlled by withholding fertilizer, especially phosphorous and ammonium-form nitrogen. Pentas are responsive to day/night temperature differential (DIF), and are shorter with a negative DIF. A Cycocel spray of 1,000 to 1,500 ppm at visible bud can be used. Higher rates may cause phytotoxicity. Always follow current manufacturer label instructions. In-house trials are recommended to determine the best rate for your location.

Common Problems
Insects: Aphids, thrips, whitefly.
Diseases:
-Pythium root rot: Soft, brown, mushy roots. Drench with Subdue, Banrot, Truban or similar compound.
-Rhizoctonia: Tan, brown or black lesions on the stem at the soil line in conjunction with good root development. Drench the soil with Chipco 26019, Cleary’s 3336, Banrot or Terraclor.
-Botrytis blight: Will usually show up in a wound to the plant on the stem or parts where the air is stagnant. If undetected, this blight will form a canker that will girdle the stem, thus wilting andkilling that part of the plant. Treatments include increased air circulation and Daconil fungicide spray applications. Refer to the Daconil label forthe specifics.
-Iron toxicity: Excessive iron levels or pH below 6.2 will cause marginal burn on leaves in upper foliage. Raise pH by adding limestone.
-Iron/Manganese toxicity: Extremely low pH can induce iron and manganese toxicity, indicated by brown or tan lesions on the foliage. Switch to a base-forming fertilizer, such as 15-0-15. If symptoms do not improve, or if the pH is below 6.0, irrigate the crop with a hydrated lime solution.Be sure to rinse foliage after application to avoid phytotoxicity.

Note: To increase soil pH, apply 12 oz. hydrated lime per 100 gal. water (90 g. per 100 l) as a soil drench. Follow up with 1 tablespoon of limestone (dolomite or calcium carbonate) per pot. Do not apply hydrated lime if the medium ammonium level is above 10 ppm (1:2 extraction). Magnesium deficiency: If magnesium is not used in the fertilization program, magnesium deficiency (lower leaf interveinal chlorosis) can develop at the time of flowering. Use fertilizers that contain magnesium during early crop development. Poor flower development: Low temperatures will prevent uniform flower development or slow flower opening.
Note: Chemical recommendations are only guidelines. Follow national and state regulations.

Green Thumb Tips
Butterfly pentas will flourish when planted in full-sun garden beds and patio containers. In northern gardens, use a spacing of 10 to 12 in. (25 to 30 cm); southern gardeners can space Butterfly plants a little farther apart – 13 to 15 in. (33 to 38 cm) is ideal. Keep plants well watered and feed regularly with an allpurpose fertilizer following package directions. This is important as pentas can suffer from too little feed.