Primula Lilac

TECHNICAL INFORMATION

Life Cycle:Perennial

Familiy, Origin:Primulaceae, Afghanistan to China

Sitelocation:Partial shade - shade

Garden Height:30 cm,11,81 inch

Natural flowertime:April - May

Crop Time:Plug crop: 9 weeks; Green pots: 18-20 weeks; Flowering pots: 8-10 months, including vernalisation

Sell Period:December-March

Seed Form:Raw Seed

Seed Count:16667 K/g

Sowing Method:1-3 seeds per plug

Germination:10-15 days at 15-20 °C, in media with very low soluble salt levels and pH: 5.5-6.0. Cover seed lightly with vermiculite after sowing. Keep soil wet (relative humidity: 100 %). Avoid direct sunlight by shading seed after sowing.

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

Growing On:4-6 weeks after sowing transplant 1-3 plants per plug tray (4x4 cm) or in packs. The first true leaf should be full developed. 6-8 weeks later transplant 1-3 plants into a pot (9-12 cm) or 3-6 plants into a container (3-5 l). Two time transplantation supports root development and young plant quality. Transplant the plant not too deep into pot.

Media:Use a well-drained, growing substrate with 15-30 % clay, 0-15 % parts (e.g. bark, perlite), 0,5-1,5 kg/m3 complete balanced fertilizer, 0-3 kg/m3 slow release fertilizer (3-6 months), iron-chelate, micronutrients, pH: 5.5-6.0.

Photoperiod / Light:Day length neutral plants. At short day condition the flower initiation is at temperatures of 8-10 °C (late summer-autumn), while the foliage formation is at long day conditions. The critical day length is 12 h. In winter and in early spring supplemental lighting (3000-4000 lx) is recommended. Protect the plants in summer against high sunlight.

Temperature:Grow at 13-15 °C or outdoors. In winter indoors frost free at 3-5 °C or outdoors. Outdoor fleece cover needed. At mid December the plants start to grow for 6-8 weeks at 8-10 °C or for 4-6 weeks at 20 °C during daytime and at 5 °C during night (quick flowering). A chilling period (vernalization) is required, but the chilling period can be replaced by a GA3-treatment.

Fertilization:Moderate fertilization levels are required. Fertilize the crop weekly with 150-200 ppm nitrogen (at 0 kg/m3 slow release fertilizer in substrate), using a potassium balanced fertilizer (N: K2O-ratio: 1:1,5). Avoid high ammonium and high nitrogen levels, because this can cause the foliage to get too big. Don't fertilize after early October. In spring fertilize 150-200 ppm nitrogen of a potassium balanced fertilizer (N: K2O-ratio: 1:1,5). Prevent magnesium deficiency by applying magnesium sulphate (0,025 %) 1-2 times and in case of iron deficiency apply iron-chelate for 1-2 times. Treat nitrogen deficiency (yellow foliage) with urea foliage fertilization. The roots are sensitive to high salt levels (above 2 g/l) in substrates. Avoid high fertilizer concentrations, it is advisable to fertilize several times with low concentrations weekly.

Cultural Hints:Avoid a too dry substrate or a too low humidity, because this can be a cause for yellow leaves. Remove the yellow foliage in time in autumn/winter in order to decrease the risk of fungi infection.