August 2014 Culture

Crop Culture Report: Begonia Bossa Nova Series By Amy Gardiner

Bossa Nova, a Begonia boliviensis introduced this spring from Floranova, is a fantastic new option for use in dramatic hanging baskets, colorful combination planters and a variety of other applications where continuous color-power is needed all season long. Bossa Nova exhibits excellent branching on a tidy, yet abundant habit, which makes it an easy, clean and profitable alternative to vegetative varieties.

Naturally branching, with short internodes, Bossa Nova easily fills out smaller pots in the early stages of growth, allowing for ease of transport, quicker finishing times and fewer plugs per pot. As it matures, Bossa Nova trails into an impressive, cascading plant, covered entirely with 2-inch, bell-shaped flowers, which provide continuous color. It thrives in a variety of climates, including high heat, and enjoys full sun to partial shade.

Bossa Nova has performed with great success in university and grower trials for the past two years and has proven to have fantastic, lasting garden performance. Success can be achieved almost nationwide, wherever long days can be administered in early stages.

It is the first boliviensis from seed to be available in a range of colors. Excellent quality pelleted seed is available in Red, Orange, White and Pink.

Culture

Media: Use a well-drained, disease-free, peat-based medium. pH should remain between 5.5 and 5.8. EC should remain between 0.5 and 1.0. Germinate without covering.

Germination stages 1 and 2 (14 days): In order to ensure great success, maintain germ temperatures between 73 to 78¡ F. Humidity should be high and media uniformly moist at all times. Do not cover pellets. Additional light of 16 hours per day will greatly enhance germination and early growth. Maintain high humidity for the first 14 days at the end of which cotyledons should become fully expanded and the humidity can be decreased to 50 percent.

Germination stage 3: At this point, humidity can be reduced to 50 percent. Media temperature can be decreased to between 68 and 72¡ F. Trays may be covered with a layer of horticultural fleece in order to help maintain the conditions and ward off sciarid fly and algae. Feed with 100- to 150ppm nitrogen from 20-10-20, 15-5-15 or 17-5-17. Keep media pH at 5.5 to 5.8 and EC at 0.5 to 1.0. Avoid high accumulation of salt levels in the media. Continue providing long-day conditions with light levels of 1,500 to 3,000 foot-candles for a minimum of 14 hours per day to ensure optimal growth and impede the formation of tubers.

Germination stage 4: Media temperature can be lowered to 65 to 68¡ F. Keep light levels 3,000 foot-candles approximately for a minimum of 14 hours per day. When roots reach the bottom of the plug, the top half can be allowed to dry between irrigations to help prevent algae formation. Feed as required with 100- to 150-ppm nitrogen from 15-5-15, 17-5-17 or 13-2-13 to tone plants.

Growing On

Irrigation: Practice a good wet/dry moisture cycle, while taking care to avoid over drying which will result in uneven and stunted growth. Water early as leaves can scorch on sunny days.

Fertilization: Bossa Nova requires moderate fertilizer. Fertilize with 150- to 220-ppm nitrogen from 20-10-20, 15-5-15 or 17-5-17 once or twice per week. Alternating with a higher potassium feed will help to keep the plants compact, while a fertilizer higher in Nitrogen will promote larger leaves and more vegetative growth. Maintain pH below 6.5 to avoid iron deficiencies.

Temperature: Maintain temperatures of 61 to 68¡ F. Temperatures lower than 60¡ F will impede growth and promote tuber formation.

Light: Day length is critical for flowering and overall best performance. Light should be provided at a minimum of 14 hours per day from germination to initiate bud, and a recommended 16 hours of light at less than 4,000 foot-candles for best quality plants. Low light levels will promote stretching and larger leaves, and less than 14 hours will stunt flowering. Higher light levels will encourage a compact habit and a lot of flowers.

Pinching and plant growth regulators: The naturally branching habit ensures an attractive and full plant throughout the growing process. Pinching and plant growth regulators are not recommended. Fertilizer and moisture management is an effective method to control height.

Diseases: Pythium and Botrytis can be avoided by maintaining good wet/dry watering practices.

Scheduling: Plug time for a 512 tray is six to eight weeks. Finish time from transplant in a 4-inch pot is seven to eight weeks with total crop time for a finished 12-inch basket (three individual plants) at 16 to 19 weeks from sow depending on conditions.

Crop Culture Report: Begonia Bossa Nova Series