New Guinea Impatiens Dept of Horticultural Science University

New Guinea Impatiens Dept. of Horticultural Science University of Minnesota ander 044@umn. edu

Impatiens hawkeri n n n New Guinea Impatiens Balsaminaceae ~8, 500 species in the genus Historically: vegetatively propagated Also—seed propagated types

Impatiens hawkeri n n n Native to New Guinea, Java, and the Celebres. Herbaceous perennial The No. 7 bedding plant (seed & veg. ) Kew Gardens received it in 1884 US: 1970 collection trip by John Creech (USDA/ARS) and Russell Siebert (Longwood Gardens)

Uses

Color Range

Flower patterns

Leaf types

‘Infinity Cherry Red’ n n n Available Veg Series (4” rooted prod. times) ‘Kokomo Pink Blush’ ‘Celebration’ 7 -9 wk ‘Celebrettte’ 6 -8 wk ‘Fanfare’ ‘Harmony’ 8 -10 wk ‘Infinity’ 6 -8 wk ‘Kokomo’ ‘Petticoat’ ‘Riviera’ ‘Sonic’, ‘Super Sonic’ 8 -10 wk ‘Super Goal’ ‘Sweetie’ ‘Tamarinda’ ‘Kokomo Salmon Frost’ ‘Petticoat Madarin’

Seed-propagated series: Tango, Divine F 1 ‘Divine F 1’, 12 -14 wk (Pan. American Seed) n Height: 10 to 14 in. (25 to 35 cm) n Spread: 12 to 14 in. (30 to 35 cm) n 85%+ Yield Potential rating ‘Tango’, 12 -13 wk (Pan. American Seed) n Height: 10 to 14 in. (25 to 35 cm) n Spread: 12 to 14 in. (30 to 35 cm)

Interspecific trailing types n n n Impatiens flaccida x I. hawkeri US Utility Patent No. 6, 924, 416 (Mario Guillen, Pan. American Seed Co. ) Veg only ‘Fanfare’ series (PP protection) 6 -8 wk (4” from rooted cuttings) 11 -13 wk (10”-12” basket)

New Guinea Production Schedule Seed (12 -15 wks. ) Plug stages 1 2 3 4 68 d 710 d 1618 d Trans- (Rarely): plant 1500 ppm B-9 750 CCC 7 -12 d 12 -14 d Stick 0. 5” cuttings: Trans 1, 000 ppm IBA plant: p. H 5. 5 -6. 5; >65 F Vegetative (10 -14 wks. ) 4”-6” pots Flower 63 d 58 -84 d (unpinched) Flower

Flowering n n n Day neutral Controlled by total light and temperature. These influence total carbohydrates through photosynthesis. Light: 4000 fc (800 µmol s-1 m-2) Temp: 77 -80 F; growth inhibited >80 F and below 63 F

Seed-propagated types n n n n Seed Count: 17, 000 S. /oz. 600 S. /g. Sowing: Cover seed lightly with coarse vermiculite. Maintain 100% humidity. Germination: 72 -78°F 22 -25°C Optimum: 78°F 25°C Days To Germ. : 6 -8 Germ. To Transplant: 70 -75°F 21 -24°C Transplant To Sale: 65 -80°F 18 -26°C

n n n n Pot Sizes: Large packs, 4 in. (10 cm) p. H 5. 8 -6. 2 Weeks To Flower (Pack): 12 -13 Garden Height: 10 -14 in. 25 -35 cm Key Tip: Feed seed-types heavier than vegetative varieties. Nutrition: sensitive to excessive SS!; 50 -75 ppm N (cutting phase/seed prod. ) 100 -200 ppm N (with micronutrients) thereafter

In general… n n Alkalinity <140 ppm; EC 1 -1. 2 mmhos p. H 5. 8 -6. 2 Only allow to dry moderately between irrigations; too dry causes leaf edge damage and bud/flower drop. AVOID WATER STRESS!

www. panamseed. com

www. panamseed. com

Common problems n Plant collapse n n Excess growth, non-flowering Foliar necrosis n Poor branching, thin plants n n Stem canker (Botrytis); Wet soil (Pythium) Too much N, late/too much Florel, low light, overwater Drying out too much, micronutrient toxicity, Botrytis Low fertilization early in crop development

High Fertilizer Salts http: //www. fischerusa. com

Cold damage (unrooted cuttings)

GA overdose http: //www. fischerusa. com

Leaf edge rolling (excessive Florel) http: //www. fischerusa. com

Grown too wet (seed): reduced G or stunting www. panamseed. com

Grown too dry http: //www. fischerusa. com

Poor flowering: high night (>70 F) or day (>85 F) temps (Erwin)

Reduced flower size (high temp. )

Too cool http: //www. fischerusa. com

Too high light http: //www. fischerusa. com

Spray damage on flowers

Diseases n INSV

Myrothecium roridum n n Fungus Round or irregularly shaped lesions on leaves Often occurs in the mist house Avoid too much water on leaves of sensitive cultivars http: //www. fischerusa. com

Powdery mildew (Oidium sp. ) n n n Fungus Spreads with wet (humid), cool conditions Start as small, circular colonies on leaf undersides, then spreading to upper leaf surface http: //www. fischerusa. com

Fungal Root Rot n n n Variety of different pathogens Control: Broad-sprectrum fungicide drenches Combination drenches of Subdue Maxx + Cleary’s 3336, Truban + Terrachlor, Truban + Cleary’s 3336 (Banrot) http: //www. fischerusa. com

Production Costs n n See spreadsheets (Rutgers University)