Collection of 10 assorted white dahlias

Plant your dahlias during fine weather in soil that has been deeply worked and enriched with e.g. dried horn or blood. Place your tuber in the planting hole and crumble the soil well to fill around it without leaving any air pockets. Your dahlia should be covered with 6 cm (2in) of soil. After planting give the tuber a litre of water. Water regularly during the first 6 weeks to help with rooting. Dahlias are sensitive to cold and need to be overwintered. In November the first frost will blacken the foliage, indicating that it's time to dig them up. Carefully remove the tubers, taking off as much soil as possible. Leave the foliage attached and let it dry out, so that the tuber can replenish its reserves. When the foliage is dry, cut the stems to 10 cm (4in) from the tuber. Spread your bulbs in a box lined with newspaper. Store away from frost in a dry, cool, and dark place.