Dahlia Night Butterfly

Plant Dahlias in humus rich, fertile, well drained soil in full sun.Pinch out the side shoots when the dahlias are around 20 cm to encourage bushy growth and more flowers during summer. Dahlias like a high nitrogen fertiliser weekly in the early part of summer but, as the flowers appear, they prefer high potash fertiliser or organic liquid seaweed.  This change will help maintain good flower production. Remove the flowers as they fade to prolong the flowering period. Make sure you pinch them out from the growing point to encourage a more bushy plant. Allow the frost to turn the foliage black, then cut back to around 15 cm. Lift the tubers, remove excess soil, and place upside down on a suitable surface in frost free conditions and allow to dry naturally. You can dust with a fungicide when dry then place the dry tubers in boxes of either dry sand or peat to over winter. Check them occasionally for fungal infection and cut out any damaged tissue then treat with fungicide. Plant to a depth of around 15-20 cm and provide deep winter mulch.