Begonia iCandy

Syngenta Flowers Technical Services

iCandy hybrid begonias feature large double flowers in vibrant, bright colors set against dark chocolate foliage. They’re a great choice for containers, hanging baskets and patio displays. This article provides a detailed look at cultivating these beautiful plants from propagation to finishing.

Propagation
iCandy Begonias are propagated vegetatively from unrooted cuttings. Growers can expect a high rate of success in rooting when proper conditions are provided. Root emergence typically occurs within 10 to 12 days. While rooting hormone isn’t necessary, maintaining a bottom heat temperature of 72 to 75F (22 to 24C) for the first three weeks is crucial. 

After roots develop, root zone temperatures can be lowered. Careful misting is key; enough to prevent wilting, but not so much as to cause foliar disease issues. Applying Capsil at 2-= to 4 oz./100 gal. within the first 24 to 48 hours after sticking can aid in hydrating unrooted cuttings without over applying mist. A 72-cell tray is ideal for propagation, with a six-week timeframe for rooting. Provide a minimum of 14 hours of light to prevent the liners from producing tubers, which will subsequently slow further growth and development.

Optimal growth requires a day/night temperature of 72 to 74F (22 to 23C). Light intensity should be 200 to 250 µmol·m-²·s-¹ initially, increasing to 300 µmol·m-²·s-¹ as the plants mature. The ideal daily light integral (DLI) is 4 to 6 mol·m-²·d-¹ initially, increasing to over 12 mol·m-²·d-¹ after root formation. Maintain a media pH of 5.6 to 6.0 and EC of 0.9 to 1.3 mS/cm Saturated Media Extract (SME) or 1.4 to 2.0 mS/cm (Press/Squeeze Method). 

Fertilization should begin at 50 ppm nitrogen once roots are visible, increasing to 100 ppm as roots develop. Cal-Mag is recommended to prevent stretching. Altercel can be applied in the final weeks of propagation at 500 to 1,000 ppm to manage growth and tone the liners. Florel (200 ppm) can also be applied during propagation around days 25 to 28 after sticking once the roots have reached the edge of the liner tray to promote branching, manage leaf size and control any early flowering.

Finishing
Be sure to transplant liners on time. Delaying transplant will cause the rooted liners to stretch and will reduce finished quality. Transplanting liners on time will also promote branching by allowing light to infiltrate through the canopy of the crop. Maintain a consistent day/night temperature of 72 to 74F (22 to 23C). A soft pinch seven to 10 days after transplant is recommended. Continue day extension lighting for 14 hours initially; natural daylength can be used for the last four weeks of production to help promote flowering prior to sales. iCandy can be grown at a light intensity to 800 to 1,000 µmol·m-²·s-¹ and DLI to 12 to 14 mol·m-²·d-¹ during the finishing stages of production. Media pH should be 5.8 to 6.2, and EC should be 1.5 to 2.1 mS/cm (SME) or 2.3 to 3.2 mS/cm (PourThru Method). Fertilize with 200 to 250 ppm nitrogen. Altercel at 500 to 1,000 ppm may be necessary depending on growth. Alternatively A-Rest at 5 ppm can be used. 

Monitor for pests (thrips, spider mites and broad mites) and diseases (Botrytis, Tospovirus, Xanthomonas). Begonias are a preferred host for broad mites; take extra care to scout for these challenging pests. Most hand lenses aren’t powerful enough to detect broad mites; ideally use 100x magnification. To improve post-harvest shelf life Chrysal Alesco can protect against ethylene sensitivity during shipping and retail.

Scheduling and crop planning

Remember to always consult the product label for specific instructions and safety precautions. Successful cultivation requires attention to detail and consistent monitoring throughout the growth cycle. GT