Penstemon Queen

TECHNICAL INFORMATION

Life Cycle:Annual

Familiy, Origin:Scrophulariaceae, North America

Sitelocation:Full sun - partial shade

Garden Height:75 cm,29,53 inch

Natural flowertime:June - October

Crop Time:Plug crop: 5 weeks; Flowering pots: 16-20 weeks; Cut flower production: 20-24 weeks

Sell Period:May-June

Seed Form:Raw Seed

Seed Count:2488 K/g

Sowing Method:3-5 seeds per plug, can be sown directly into final pots

Germination:7-14 days at 18-24 °C, in media with very low soluble salt levels and pH: 5.5-7.0. Requires light for germination. Cover seed lightly with vermiculite after sowing. Keep soil slightly moist but not wet. Avoid direct sunlight by shading seeds after sowing.

Plug Culture:From Stage II* reduce the soil moisture, but the plug should not dry out and reduce the temperature to 16-18 °C. Do not let soluble salt level rise above 0,75 EC. Start fertilization at 50-75 ppm nitrogen in a well balanced formula. During Stage III and Stage IV fertilization levels can be increased to 150 ppm.

Growing On:3-4 weeks after sowing transplant 1 plant into a pot (8-15 cm) and 1-3 plants into a container (3-5 l). For flowering pot production ensure good pot size, to encourage root growth, thus improving plant quality. Plant cut flowers (frost free) in 40x40 cm space and use nets to keep the stems upright. Protect the plants against frost at night .

Media:Use a well-drained, growing substrate with 15-30 % clay, 0-20 % parts (e.g. bark, perlite, sand), 1,5-3 kg/m3 complete balanced fertilizer, 0-3 kg/m3 slow release fertilizer (3-9 months), iron-chelate, micronutrients, pH: 5.5-7.0. Field: sandy humus soils with good drainage. Standard fertilization: 80-100 g/m2 of a slow release fertilizer.

Photoperiod / Light:Day length neutral plant. Keep light level high, because high light intensity and long day (16-18 h) improve the flowering and the pigmentation of the flowers and the leaves is more intense than at low light intensity. In winter and in early spring supplemental lighting (at least 10 Watt/m2) is recommended. Light deficiency supports excessive stretching of the shoots.

Temperature:Grow at 12-18 °C during day time and at 10-13 °C during night or outdoors. P. hartwegii does not tolerate frost. P. hartwegii can also be brought to flower earlier in the polytunnel.

Fertilization:High fertilization levels are required. Fertilize the crop weekly with 100-150 ppm nitrogen (at 3 kg/m3 slow release fertilizer in substrate), using a complete balanced fertilizer. Avoid high ammonium and high nitrogen levels. Prevent magnesium deficiency by applying magnesium sulphate (0,05 %) 1-2 times and in case of iron deficiency (above pH 6.0) apply iron-chelate 1-2 times. Field: If necessary according to analysis, fertilize the soil additionally with a potassium balanced fertilizer. Take care of a good micro nutrition supply to the plants.

Cut Flowers:Cut flower stems can be harvested, when 30 % of the flowers per stem are just open. Vase life: 5-8 days.

Cultural Hints:Cultivate during the growth period with a constant water supply, because the roots are very sensitive to substrates that are too wet or too dry. Treat pots with a fungicide against Botrytis after transplanting, for wintering and in spring. Remove regularly the faded flowers to support a following flowering.