Flower diversity encourages pollinators
Most of us want to welcome wildlife into the garden. Who, after all, would turn their back on a butterfly basking in the begonias or not get a buzz (literally) out of a cloud of bees making merry in the marjoram. But wait a minute… what exactly do bees do beyond making us feel like we are some sort of eco warrior?
The bugs – ladybirds, the bees, butterflies, moths and flies – don’t all hang out because of us. They come, drawn by greed, to gather up the delicious goodies flowers have to offer, both the dusty yellow pollen which is rich in protein – perfect for feeding young – and possibly more tempting still, the sweet sugary nectar which provide an instant energy hit.
Not all flowering plants produce these goodies for the bugs but the ones that do, do it not out of the kindness of their hearts but to trick them into fertilising their flowers as the bees squeeze, shake and rub themselves at the dinner table, spreading male pollen onto ripe female stigmas. It’s a sort of progressive meal with casual sex thrown in. But that job of pollination is more important than you think. It underpins our food production, and ensures the annuals and biennials in your garden seed about and bloom next year.
While most of the grains and cereals of the world are wind pollinated, it’s reckoned that 80 per cent of all crops require insect pollinators if they are to set seed and fruit. When you think about it, even cows and sheep need successful pollination of plants such as clover and other nitrogenfixing legumes to keep their grasslands nutrient rich.
And while we sow vegetables such as carrots, spinach, radish and tomatoes – and don’t need or want them to set seed – without pollination and seed setting, the specialists who supply us and the farmers with seeds would go out of business.
According to Dr Brad Howlett from Plant and Food Research, New Zealand is a big player on the world stage when it comes to producing new, top class food seed varieties. He says that while the beekeepers in New Zealand are doing a good job managing the potentially devastating effects of varroa mite, farmers still need to bring in managed colonies of pollinators every year for crops such as avocado, berries and kiwifruit to get fruit set, and there is potential for serious competition for the available hives.
In our gardens, we can play our part, encouraging as many insect pollinators as possible. Not just for our benefit – the pollination of our orchards, berries and squash – but for the ecosystem as a whole. Honeybees are great at pollination and numerous, but like ladybirds and bumblebees, they are merely welcome exotics doing a good job.
What we need to change, says Howlett, is our attitude to the less glamorous native insects that are equally important in the pollination game. Dingy moths, hoverflies that uncomfortably masquerade as wasps yet cannot sting, beetles and flies all play their part pollinating our native flowers. Some, like the hoverfly, even have a second trick up their sleeve – their larvae vacuum up dastardly aphids and caterpillars as they go. Yet we don’t seem to welcome them as gladly as we do a catwalking butterfly.
And wouldn’t it be exciting to feel by our planting that we are encouraging our truly native bees? Of the few species of native bee, most live solitary lives and are extremely reluctant to sting – unlike honeybees and bumblebees. So fill your patch with flowers, especially native ones more in rhythm with the lifecycles of native bugs. Perhaps provide a bank of sunny soil for them to dig into and nest too.
The best way to draw in pollinators of all ilks is relatively easy – plant as many flower types as you can. Put them in an insectfriendly place – a sunny, sheltered spot is ideal.
Avoid the fussy double flowers which insects find hard to climb into and spread the season of flowering wide. While manuka and metrosideros may be great in spring, don’t forget rata, hebe and hoheria for summer and beyond.
A diversity of flower shapes and sizes is important; colour less so (red flowers tend to be designed for pollinating birds; flies and bees prefer yellow, orange and white).
Research in Britain suggest that pollinators do not often discriminate between native or exotic flowers but it’s always nice to support your local flora by choosing plants suited to home soils and climate.
Make a note of the natives you see in your locality that are alive with insect life. Cordylines, flax, hebe, hoheria, olearia and tea tree are a good basic starting kit.
Forest and Bird has more information on commonly seen pollinators.
Download Howlett’s list of great native plant species to support pollinator diversity here.