Butterflies, like so many of our insects, are under increasing threat from pesticides and loss of habitat. They will visit any garden and we have the opportunity to attract up 20 species if we work at it! There are a number of plants that will help to attract butterflies but location is nearly as important as plant selection. When planning a butterfly “patch”, pick a sunny sheltered spot, and plant a number of each plant variety in blocks. Nectar across the season is vital for butterflies, especially in the leaner, spring months, as these are key for butterflies coming out of hibernation. Autumn flowers are key for building up their strength for getting through the winter.
Prolong flowering by dead-heading regularly and watering well as necessary. Water is especially essential for nectar production. Avoid insecticides as much as you can – completely if possible. Butterflies are delicate and very susceptible to chemicals.
Caterpillars are also key of course, and there are some amazing looking beasts that come under this heading. I will cover how to encourage these and moths, which are so key to pollination of many species, next month.
The list of plants is fairly long and the RHS publish a list on the Internet, as do many butterfly conservation sites. Spring nectar producers for butterflies include early Buddleia varieties, Hebe, Honesty, polyanthus and violets. The end of season favourites include ivy (also important for bees), michaelmas daisies and sedum spectabile (beware of non-nectar producing varieties).
You can target specific species – in which case best to look up their favourite food on the Internet. The “top 5” for a wide variety of butterflies are usually quoted as follows:
Buddleia (The butterfly bush) - easy to grow in almost any soil. Different varieties will flower in pink, red, purple, and white. Usually in bloom through July and August. Several varieties, including the 'basic' Buddelia davidii, the yellow pompoms of Buddleia globosa, and the hybrid of the two, Buddleia x weyeriana. The lilac buddleias are said to be best and these are an absolute favourite with 18 species including 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.
Verbena Bonariensis - stems up to a metre tall support heads of lavender coloured flowers from August to October. Easy to grow from seed, plant March-April in well-drained soil. Can provide useful height at the back of a border.
Lavender - lilac-blue flowers grow on spikes through the summer. Plants can be used for edging beds or grown to form an attractive, low-growing hedge. Needs a sunny, sheltered position in well-drained soil. Lavender should be planted in April or May and pruned back to encourage bushy growth.
Perennial Wallflower (Bowles Mauve) - produces a profusion of sweet-scented purple flowers from April all through the summer. Wallflowers make great bedding plants and will grow well in full sun or light shade. Plant in well drained soil.
Marjoram (Oregano) - a perennial herb, growing from 20 to 80 cm tall. White, pink or purple flowers grow on spikes from June to September. A good edging plant and useful ground cover, requiring little maintenance. The smaller varieties also do well in rock and alpine gardens.