Echium : Greenhouse Plants
C – cool, minimum of 7°C (45°F)
There are some hardy species but the larger ones are not dependable even in milder districts. The Abbey Gardens on Tresco in the Scilly Isles usually has some magnificent specimens growing outside and even has some varieties of its own. Most commonly grown in the greenhouse is Echium wildprettii, a hairy biennial from the Canary Islands which is by no means easy to keep healthy. During the winter they have a tendency to rot if even slightly too damp. They like cool dry airy conditions and just enough water to survive on. However, if you are successful in nursing them through the winter you will be rewarded by a spike of pale red flowers which will elevate the total height of the plant to 1.2 m (4 ft). Seed is readily produced and can be collected for a succession of sowings every year. Sow the seed in March or April at a temperature of 15-18°C (60-65°F). E. fastuosum is a compact perennial from the Canaries known as the Pride of Madeira. The hairy leaves are an attractive soft white and the flowers are deep blue. E. pininana has a very tall flower spike reaching to 4 m (12 ft) when planted out in a cool house border. The spike is full of small blue flowers and is an impressive sight.