Culture guide
- Uses:Pot, border and mixed container
- Exposure:Sun
- Garden height:12″ / 30 cm
- Crop time:9-10 weeks
- Sowing method:1-3 seeds per plug
- Germination*:5-10 days at 70 °F (21 °C), cover seed lightly with vermiculite after sowing.
- Growing On:Transplant plugs after 2-3 weeks. Grow on at 50-55 °F (10-13 °C). Calendulas are cool weather plants that are best produced for spring or early fall sales.
- Media:Use a well-drained, growing substrate with 10-30 % clay, 0-15 % parts (e.g. bark, sand, perlite), 1-1,5 kg /m³, complete balanced fertilizer. Iron-chelate, micronutrients, pH 5.8-6.5.
- Temperature:Grow at 10-15°C (50-59 °F). Calendula does not grow at temperatures below 8°C (46 °F). A cool cultivation in early spring in polytunnel or cold greenhouse is possible.
- Fertilization:High fertilization levels are required. Fertilize the crop weekly with 100-200 ppm nitrogen (at 2 kg/m³ slow release fertilizer in substrate), using a complete balanced fertilizer. Avoid high ammonium and high nitrogen levels. High nitrogen levels cause delay in flower initiation and smooth stems. Prevent magnesium deficiency by applying magnesium sulphate (0,025%) 1-2 times and in case of iron deficiency apply Fe-Chelate for 1-2 times.