These evergreen plants are called fascicularia bicolour and are native to Chile where they can be found growing as epiphytes, writes Head Gardener Sarah Syborn.
They are hardy bromeliads and relatives of the pineapple. The leaves are spiny and the flowers are deep circular rosettes covered with pale blue inflorescences. They are fairly unusual in the UK but I thought I would experiment with them as they are said to grow in difficult dry situations.
They seem happy in Warwick Square where after some considerable time they have flowered for the past couple of summers. In Chile they are pollinated by hummingbirds but sadly none are available in Pimlico!