(Catharanthus) Cultural Information Vinca Vitesse, Viper

Plug Production
Sowing/Media: Use a well-drained, disease-free, peat-based plug medium with a pH of 5.5 – 5.8 and EC <0.75 mmhos (saturated paste). Cover seed with coarse vermiculite after sowing to provide dark conditions for better germination.

Germination (Stages 1 and 2): Keep medium uniformly moist until seedlings are hooking above covering, then dry down covering to control stretch and improve rooting. Soil temperature should be 75 – 80°F, as vinca like it warm to germinate. Keep light levels <1500 footcandles until cotyledons are open. Germination time is 7 – 10 days.

Stage 3: Soil temperature should be 68 – 72°F, no lower. Keep on drier side and lower humidity for best rooting, height, and disease control. Light levels should be around 3000 footcandles. Feed every other watering with 100 – 150 ppm N from 15-5-15, 17-5-17, or 13-2-13. Keep media pH 5.5 – 5.8, definitely < 6.5, and media EC 1.0 – 1.5 mmhos (saturated paste).

Stage 4: Soil temperature can be lowered to 65 – 68°F. Avoid too cool temperatures, as they promote poor rooting and increase root rots. Keep on the drier side, with light levels 3000 – 4000 footcandles. Use low NH4 feeds, but monitor media pH closely to keep <6.5.

Plant Growth Regulators: Use sprays of B-Nine (800 – 2500 ppm), A-Rest (2 – 7 ppm), or Sumagic (1 – 5 ppm, in warmer climates only). Bonzi sprays will cause black spotting on leaves. Do your own trials to avoid overdosing, as vigor of varieties, weather conditions, and cultural practices directly affect how much growth regulators to use.

Crop Time: 5 – 7 weeks for 512 plugs, 6 – 8 weeks for 288 plugs, depending on temperature and light levels. Using HID lights during low light periods will speed up growth due to warmer leaf temperatures.

Common Problems: Pythium, Rhizoctonia, Thielaviopsis, aerial Phytophthora, Botrytis, Alternaria leafspot, upper yellow leaves – media pH >6.5 or low iron.

Growing on to finish
Container Size: Cell packs to 4-inch pots

Media: Transplant into a well-drained, disease-free, peat-based growing mix with pH of 5.5 – 5.8 and EC <1.5 mmhos (saturated paste). Avoid saturating media with water right after transplanting to control root rots. Use half-saturation technique for watering until roots to sides of container. Do not transplant any plugs showing upper yellow leaves!

Temperatures: Keep soil temperatures 70 – 72°F to root out, then lower to 68 – 70°F to grow on, no lower. Vinca grows better the warmer the temperature.

Light: Keep light levels 3000 – 5000 footcandles or higher.

Irrigation and Fertilization: Do not keep too wet! Grow on the drier side with some wilt. However, watering lightly but frequently will create more foliar diseases. Feed 1x/week with 150 ppm N from 15-5-15, 17-5-17, or 13-2-13 (monitor media pH). Keep media pH 5.5 – 5.8, definitely <6.5, and media EC 1.0 – 1.5 mmhos (saturated paste), no higher.

Plant Growth Regulators: Use sprays of B-Nine (1000 – 5000 ppm), A-Rest (2 – 7 ppm), or Sumagic (2 – 3 ppm, in warmer climates) as needed. Bonzi will cause black spotting on leaves. Do your own trials to avoid overdosing, as vigor of varieties, weather conditions, and cultural practices directly affect how much growth regulators to use.

Common Problems: Pythium, Rhizoctonia, Thielaviopsis, aerial Phytophthora, Botrytis, Alternaria leafspot, upper yellow leaves – media pH >6.5 or low iron.

Crop Time: Vinca Vitesse 5 – 7 weeks, Vinca Viper 6-8 weeks, depending on plug and container size, temperature, and light levels.