7/30/2014
Kabloom: The First Calibrachoa from Seed
Lisa Lacy
With the recent introduction of the world’s first calibrachoa from seed, I’d like to share our culture guidelines, developed after trialing globally and extensively across North America. Kabloom seed is available as single-seeded pellets, which are the same size as pelleted petunias.
Plug production
Stage 1: Seed can germinate in light or dark; covering isn’t required. Keep moisture at level 5. The optimum media temperature is 73F (22.5C) for germination. At this temperature, radicle emergence occurs in 5 to 7 days.
Germination temperature and varieties determine the timing of radicle emergence:
Fast-germinating varieties:
Kabloom White
Kabloom Deep Pink
Kabloom Yellow
Stage 1 at 75F (25C) for 5 days
Stage 1 at 68F (20C) for 5 to 7 days
Slow-germinating varieties:
Kabloom Deep Blue
Kabloom Red
Stage 1 at 75F (25C) for 7 to 10 days
Stage 1 at 68F (20C) for 10+ days
Stage 2: Moisture to level 4 and begin to decrease temperature to 68F (20C). Light requirements of ≥10 moles·m−2·d−1 will help to minimize stretch. Growth regulators can be administered in stage 2: Flurprimidol (Topflor): 2 to 3 ppm spray on day 7 to 10, then every 10 to 14 days as needed.
Paclobutrazol: 3 ppm spray on day 7 to 10, then every 10 to 14 days as needed.
Daminozide: 2,500 ppm spray on day 7 to 10, then every 10 to 14 days as needed. Note: Daminozide can cause chlorotic stippling on Kabloom Red and to a lesser degree on Kabloom Yellow. No stippling with paclobutrazol or flurprimidol.
Stage 3: Cycle moisture levels between 2 and 4; do not allow to wilt. Decrease temperature to 64F (18C) and maintain a DLI of ≥10 moles·m−2·d−1.
Stage 4: Cycle moisture levels between 2 and 4; do not allow to wilt. Decrease temperature to 55 to 64F (13 to 18C), no less than 55F (13C). A morning DIP/Drop of -5F for height control is also effective. Maintain a DLI of ≥10 moles·m−2·d−1 .
Plug crop time
Tray Size: 288 Crop Time in Weeks: 5 to 6
Tray Size: 128 Crop Time in Weeks: 7 to 8
Tray Size: 105 Crop Time in Weeks: 7 to 8
Tray Size: 72 Crop Time in Weeks: 7 to 8
Transplant to finish
Finish culture is similar to vegetative calibrachoas. Maintain pH of 5.5 to 5.8 with the same nutrition program as vegetative calibrachoas. Pinch or shear if pullable plugs are stretched, overgrown or spindly.
Drench paclobutrazol at 1 to 3 ppm 7 to 10 days from transplant. Reapply as needed. Note: Kabloom White is more sensitive to paclobutrazol drenches. Therefore, a lower rate or less frequent applications are recommended for this variety.
Minimum Hours of Day Length Required by Variety:
10 hours: Kabloom Yellow and Kabloom White
10.5 hours: Kabloom Red
11 hours: Kabloom Deep Blue
12 hours: Kabloom Deep Pink
Container Sizes and Total Crop Time from Sow to Salable Stage:
4- to 6-in. (10- to 15-cm) Pots and Quarts/1 PPP: 12 to 13 weeks
10-in. (25-cm) Basket/3 PPP: 14 to 15 weeks
12-in. (30-cm) Basket/5 PPP: 14 to 15 weeks GT
Lisa Lacy is the Global Product Manager for PanAmerican Seed. Find culture and product details at www.panamseed.com.