Fancy a Chinese?

from The Oxford Times

There's always a great deal of debate in the gardening world about whether or not native plants are more desirable to native wildlife.

I have a suspicion that when it comes to sap-sucking insects like aphids, there is a definite preference for native plants rather than alien species.

I base this on watching colonies of aphids carefully selecting wild scabious stems when offered an intertwining mixture of alien and native scabious species.

However when it comes to nectar, insects simply select the most sugar-rich nectar they can find regardless of whether the flowers emanate from a native or an alien plant.

This is why buddleja davidii, a shrubby plant from China, attracts 18 species of British butterfly. These are the Brimstone, Comma, Common Blue, Gatekeeper, Green-veined White, Holly Blue, Large Skipper, Large White, Meadow Brown, Painted Lady, Peacock, Red Admiral, Small Copper, Small Skipper, Small Tortoiseshell, Small White, Speckled Wood and Wall Brown.

They all choose the buddleja in preference to any other plant and if you get up close you can actually breathe in the honey-rich fragrance for yourself.

This makes the alien buddleja the best British butterfly plant for your garden and in all 37 different types of butterfly have been recorded on buddleja flowers in Britain.

Always plant in sunny, sheltered position where afternoon sun falls. The extra warmth produces maximum nectar. Some gardeners maintain that certain colours of buddleja are more favoured than others. But I have always grown the pale-lavender, Lochinch', the almost-black Black Knight' and the rich-lilac Dartmoor' and I haven't noticed any significant differences.

Lochinch' (a hybrid between B. davidii and the rather tender B. fallowiana) is a refined, shorter buddleja with small lavender-blue flowers and narrow, silvered leaves.

It seems to have a longer flowering time than most buddlejas and mixes very well with silvered plants with pale-yellow flowers. Its gracefully arching stems retain some winter leaf too and this buddleja should get a lighter prune than the others. If you have a small garden Lochinch' is perfect.

Black Knight' is probably the darkest form of B. davidii and it looks sensational covered with fast-flying Painted Ladies, jewel-eyed Peacocks and velvet-winged Red Admirals. It is also very hardy and bears shorter, fatter spikes.

Dark-flowered buddlejas seem to brown-off less than paler-flowered varieties probably because there is more pigment than air in the petals. For this 'browning' reason I avoid all white and paler varieties. However all buddleja flowers eventually darken and are best cut away as they fade. This encourages more flowers and prevents unwanted seedlings.

Dartmoor' is a one you'll either love or hate because the flower spikes are joined to form collection of rich, lilac-purple flower spikes which hang rather like fingers on a hand.

It's tall, reaching 15 feet, but the substantial flowers make an impact on the eye and I rate it for its heavy presence. All forms of B. davidii need to be hard-pruned once a year in late spring in order to keep their vigour. They should never be cut down hard before the winter.

Dartmoor' was collected in the wild near Yelverton in Devon by a retired American gardener. He spotted it growing on a rocky moorside ravine in 1971. This is a position B. davidii often adopts in its native China and all buddlejas need sun and good drainage in order to produce those alluring flowers.