THE COLOUR OF SKY

Here, from the opposite ends of the Earth, are two of the most dramatic sky blue flowers: • Himalayan poppy ( Meconopsis betonicifolia) Stems are nearly 2m high, sporting 30 blooms up to 10cm across – that’s this poppy at its happiest, according to one of my books, though I never managed anything approaching this. Give yourself a fighting chance by emulating as closely you can its central Asian habitat of woods and scrubs alongside alpine meadow streams: grow it in moderately rich, well-drained soil in partial shade – preferably from hot afternoon sun – and sheltered from strong winds. Never stint on watering. • Chatham Island forget-me-not

( Myosotidium hortensia) Big, glossy bright-green pleated leaves grow up to 50cm across. Its fabled flowers, which range from a pale pinky blue to a deep azure, are borne in 15cm wide pyramidal clusters.

Once you suss out a good spot for it, this megaherb will reward you for years, with self-seeded seedlings replacing older plants as they die. It is however, not always easy to provide the ideal spot or conditions! On the islands, it grows along the coast, so in your garden, give it semi-shade and never let the soil dry out, as it is shallow rooted.