We are about to move for a while from the main Caterpillar Foodplant theme of our website to discuss Nectar Plants, but we won’t of course be losing sight of the fact that without caterpillar foodplants there won’t be any adult butterflies to drink the nectar. An abundant supply of nectar is essential to fuel the activity of most, but not all, butterflies and moths, as they search for a mate and a suitable place to lay their eggs.
Limited Caterpillar Foodplant Choices As we have seen, butterflies are highly selective in their choice of leaves on which to lay their eggs, due to the need to provide a high quality, nutritious diet for their caterpillars - which usually means fresh, young leaves in a warm, sheltered spot. The leaves also need to provide camouflage, and in many cases toxic chemicals that the caterpillars can safely concentrate within their bodies to make themselves unpalatable to birds and other predators. In these days of shrinking habitats, finding the right plant in the right place becomes more and more difficult.
A Bigger Choice of Nectar In contrast, when it comes to satisfying their own thirst for nectar, butterflies are far less selective. But they do have preferences, and to attract as many types of butterfly to your green space or garden as possible, the wider the range of nectar plants the better. Most commercial seed mixes contain twenty or so. They are typically selected by the suppliers to provide nectar over as long a season as possible, from when the first butterflies emerge from hibernation in spring right through to when the second or third brood are on the wing as autumn approaches. They also include species with long-tubed flowers for those bees, butterflies and moths that have a long proboscis.
Nectar-rich Wildflower Mixes for Every Location Most good commercial suppliers have mixes geared for specific types of terrain. Scotia seeds for example have an especially intriguing selection including a Dry Meadow Mix, Wet Meadow Mix, Flowering Lawn Mix, Hedgerow Meadow Mix, Northern Haymeadow Mix, Highland Grassland Mix, Coastal Meadow Mix, Urban Pollinator Meadow Mix, Green Roof Mix, Bee, Bird and Butterfly Mix, Coastal Dry Places Wildflower Mix, Flowering Lawn Wildflower Mix, get Nectar-rich Quick Mix, Haymeadow Wildflower Mix, Hedgerow Wildflower Mix, Pond-edge Wildflower Mix, Wetland Wildflower Mix and a Woodland Wildflower Mix.
With most of the hard work having already been done for us by the seed companies, it’s just a case of deciding which mix best fits our location, and if we have special favorites or want extra caterpillar foodplants, adding them to it. Some wildflowers are tolerant of a wide range of conditions and appear in most mixes, while others are far more dependent on specific conditions of wet or dry, chalk or acid soils and so on..
A word of caution. There are some wildflower mixes on the UK market which turn out to include the wildflowers of America, South Africa and elsewhere. They may produce just as much nectar and pollen as British wildflowers but our insects have not evolved to use them as larval food plants, so do as they do and avoid them. Always make sure that you only choose companies like Scotia Seeds, Emmorsgate and others that either grow their own stock in the UK or source it from growers who do. Most of our wildflowers also grow on mainland Europe, but to keep your stock pure, whatever country you live in, buy as locally as possible.
Nectar-rich, but where does Pollen fit in? Should we focus on those wildflowers that produce most nectar, most pollen, or both? Our native butterflies don’t eat pollen – bees do, but not butterflies - so if our main aim is simply to attract butterflies, It’s their yield of nectar that will be of most interest to us. If our aim is also to provide sustenance for a colony of honeybees or bumblebees it will be different. It's important not to confuse the life style and diet of bees with that of other insects. Bees are extremely unusual insects for at least two reasons. Firstly their larvae are cared for and fed by the adults. A few other kinds of social insect including ants and termites and a few species of wasp adopt a similar strategy, but the vast majority of insects, including butterflies and moths, after carefully choosing an auspicious place to lay their eggs - in terms of camouflage and proximity of food - leave their larvae to fend for themselves.
Secondly, bees feed themselves and their young exclusively on nectar and pollen, in contrast to butterfly caterpillars which avoid them in favour of leaves and buds.. . Even adult butterflies (with some specialised tropical exceptions) only drink nectar, and fail to avail themselves of the flower's pollen, although they might get contaminated by it and carry it to the next flower they visit, inadvertently fertilising it.
Setting up Home Once we have equipped our area of land with nectar stations at which passing butterflies can refuel, we don’t really want them to continue their journey. We would prefer them to stay, set up home and produce the next generation. So if we wish to create a breeding ground for butterflies, the next step is to see how well the commercial pollinator mixes supply the necessary caterpillar food plants. It’s easy enough. Just go through a list like ours of caterpillar food plants, and identify those suitable for the caterpillars of the butterflies likely to be around in your part of the country. Then check that they are in the commercial wildflower mixes of interest to you, and if they are not - usually because they don't produce pretty wild flowers for pollinators – simply purchase them separately, either as seeds or plug plants. The advantage of plug plants is that they provide a head start over everything else growing from seeds. To persuade butterflies to actually breed in your garden rather than just stopping briefly to refuel at its nectar pumps, it’s important that the caterpillar foodplants always take precedence.