A neglected garden is likely to get more butterflies than a pristine patch, as stinging nettles (Urtica urens) and other nettles are the only plants on which the lovely native yellow admiral lays its eggs.
It's a similar tale with the red admiral and if you balk at growing nettles for them, they have other uses.
For a nitrogen-rich fertiliser, let nettle tops rot in a bucket of water, then use the liquid to water lettuces, spinach and other greens; add the plants to the compost bin, where they are reputed to speed up decomposition; and if you want to eat it, the sting disappears when the leaves are boiled or steamed.
Self-introduced into New Zealand, their numbers have risen since the push to plant their favourite food, the swan plant (Asclepias physocarpa).
Garden centres sell the plants with tiny caterpillars but the numbers are often too great for a single swan plant, so growing a few extras from seed will help prevent infant mortality. For a more decorative swan plant, try A. curassavic, a Butterfly Flower blend, which has bright flower heads in red, orange, dark pink and white.
Black-and-white magpie moths lay their eggs on ragwort, groundsel and Senecio. Their furry caterpillars also have a taste for cinerarias, so these common moths can be attracted by sowing one of the less expensive varieties in a cool, moist corner.
One no gardener wants is the cabbage white butterfly, whose green caterpillars gobble up cabbages and other brassicas, including swedes.
Derris dust kills the caterpillars but a more environmentally friendly answer is to make a mesh-covered frame so the adults cannot get to the plants to lay their eggs.
Many butterflies love Buddleia davidii but, as this is now a pest plant in many parts of New Zealand, other options should be considered.
My top five for bees among summer-flower annuals are Phacelia (scented lavender flowers), cornflower (blue, pink and white), calendula, alyssum and larkspur. Heading the perennials list are autumn-blooming sedums, which attract so many bees that it sometimes seems each flower head has standing room only.
Other perennials to bring in the bees are thyme, hollyhocks and bergamot (Monarda didyma); lavender, rosemary and old roses are bee-attracting shrubs; while for trees, get two for one by growing fruit trees. The spring blossom is pollinated by bees and the gardener reaps the reward of apples, plums and pears.
What's the difference?
Butterflies are seen in the daytime and moths at night, right? Wrong. One of our most common day-flying butterflies is the magpie moth, whose furry black-and-orange caterpillars are often seen on groundsel.
Have a closer look and you'll be able to tell the difference: butterflies have smooth antennae with clubbed ends, while moths have feathery antennae.
One of the best small guides to common moths and butterflies is Butterflies and Moths of New Zealand, by Otago's Brian Patrick and Brian Parkinson.
Alas, it is now out of print, but it's worth trawling second-hand bookshops for a copy, as the photographs are outstanding aids to identification.
There are few things that lift the spirits more than butterflies and bees in the garden. Gillian Vine looks at some of the plants that attract them.
