One of the most popular ways of assisting with butterfly conservation is by planting lots of suitable food plants in the garden. The most “helpful” plants are those which flower late in the season, these can make a real difference to those butterflies which roots or hibernate, as they need to build up their fat reserves for the long winter ahead. The flowers need to be rich in nectar and also attractive to butterflies in the first place.
Good examples include the Iceplant (Sedum Spectabile), Valerian (Valerianaceae Spp), and the Michelmas Daisy (Aster novi-belgii). It is not so important to have plants that flower during the summer as there are usually plenty around for the butterflies to choose from. However, if like most people you want to encourage butterflies whenever possible, it’s a good idea to plant a wide range of flower species to maintain a food supply at all times. Those that flower early in the year will help the winter’s survivors in early spring.
Some people also plant things which will be suitable for larval food plants as well as for the adult butterflies. Nettles are very god for many of the “Nymphalids” so it is common for several well-meaning gardeners to leave a patch somewhere out of sight.
Unfortunately this is only too often behind a shed or under some overhanging trees where they won’t get in the way. They then feel justified to say that they have “done their bit” in the cause of conservation; sadly though the patch is usually damp and lacks sunlight. This will nearly always be rejected by discerning female butterflies, as they will not lay eggs where they are likely to fall victim to fungal problems caused by lack of warmth ventilation and light.