March 2021 Culture, Variety Info

Culture Report: Catharanthus Soiree Kawaii Series By Delilah Onofrey

Looking for heat-loving annuals? Soiree Kawaii catharanthus from Suntory Flowers are tiny but terrific! These little dynamos thrive in the harshest southern conditions, while also looking great all summer up North. The word “kawaii” means cute in Japanese, describing the flower size and shape. Think of these varieties as vinca’s cute little sister!

Advantages include an amazingly compact habit with superior branching, producing more flowers on shorter internodes in small pots. Attractive glossy foliage complements the profusion of blooms, creating tidy mounds of color.

Soiree has caught on with major growers in the South, most notably Florida and Texas. But the word is spreading as growers, retailers and landscapers have seen the performance at garden trials throughout the country. Customers have been amazed by the landscape performance May through October.

It’s the perfect season extender. Plants finish nicely in small pots, but also fill out larger pots with superior branching ability. It is excellent in mixed containers with other heat lovers, too!

TIMING

Crop times are as follows:
4-inch pots, one liner, six to eight weeks
6-inch pots, two to three liners, 10 to 12 weeks
1-gallon pots, two to three liners, 10 to 12 weeks

ROOTING

Stage 1: Cutting arrival and sticking
Cuttings may be stored at 60 to 65° F for up to 24 hours. Ensure boxes are open. Stick cuttings in a substrate with a pH of 5.4 to 5.8. Rooting hormone is not recommended. Abnormal growth may result.

Stage 2: Callusing
Maintain substrate temperature of 75 to 78° F. Maintain air temperatures of 75 to 85° F during the day and 65 to 68° F at night. Maintain light intensity of 500 to 1,000 foot-candles. Begin foliar feed of 50- to 75-ppm nitrogen from 15-0- 15. Keep the substrate moist so that water is easily squeezed out of it, but not waterlogged. Provide plenty of room between plugs or strips for good air movement. Transfer cuttings to Stage 3 in 10 to 14 days, once 50% of the cuttings begin rooting.

Stage 3: Root development
Maintain substrate temperature of 70° F once rooted. Maintain air temperature of 75 to 85° F during the day and 65 to 68° F at night. Increase light intensity to 1,000-2,000 foot-candles. Begin drying out the substrate once roots are visible. Fertilize with 100- to 150-ppm nitrogen once a week from 15-0-15, alternating with 20-10-20. Roots should develop in 14 to 21 days.

Stage 4: Toning rooted cuttings
Lower air temperature to 70 to 75° F during the day and 62 to 68° F at night. Increase light intensity to 2,000- 4,000 foot-candles. Move liners from the mist area to an area of low humidity. Fertilize with 150- to 200-ppm nitrogen once a week from 15-0-15 alternating with 20-10-20. One pinch at this stage is recommended, not required. Rooting should be completed in 35 to 40 days. Mist only as needed to prevent wilting. Excess water is detrimental. Keep foliage a lot dryer than you would with other species.

GROWING ON

pH/EC: 5.4 to 6.0 / 1.0 to 2.0
Fertilization: 200- to 250-ppm nitrogen
Water requirements: Moderate. Water plants prior to wilting. Allow substrate to dry down between waterings.
Light levels: High
Growing temperature: 75 to 85° F
Holding temperature: 60 to 70° F
Pinching: One pinch is recommended — always ensure you have at least two nodes, especially in cool periods.
Plant growth regulators (PGR): Optional — For best results, use B-Nine (daminozide) at 2,500 to 5,000 ppm.
Pests & diseases: Insects/mites to monitor are whitefly, aphids, western flower thrips, red spider mite. Diseases to prevent are Botrytis, Thielaviopsis, Corynespora, Phytophthora, Pythium and Rhizoctonia.