where the prize lurks. Plants are hot wired to flower at particular times. This can be stimulated by day length or temperature or a combination of both. It would be literally fruitless to put all your energy into producing pollen when there is no other plant ready to receive it, or active pollinators to distribute it. Once lured into the flower, pollen is brushed onto the body of the visitor which is subsequently transferred to the stigma of the next flower it visits. Plants have developed with specific pollinators in mind. Long tongued bees and butterflies take advantage of the deep blooms of foxgloves and aquilegia, whilst flies, wasps and beetles, sup at the shallow flowered cow parsley and geraniums. Insects are not the only pollinators; red hot pokers are visited by sunbirds in their native South Africa, and ants, hummingbirds and bats all have their roles to play. The other form of attraction is scent. Winter flowering shrubs, such as Daphne bholua ‘Jacqueline Postil’ and Viburnum x bodnantense, often have small flowers but are highly scented. At a time when insects are few and far between a heady perfume is the perfect clarion call. Night scented flowers, such as evening primrose and honeysuckle target nocturnal moths.
“What gardener hasn’t studied a reluctant plant, willing it to form a f lower bud and then watch with interest, and trepidation, as it begins to swell and unfurl?” How flowers are arranged on a plant is varied. There are individual blooms, and multiple flowers in formations such as racemes and umbels. Composites, such as sunflowers, have a myriad of tiny individual flowers surrounded by sterile ray florets. In pre-DNA days, flowers were used by botanists as the principal method of categorising plants. Cross pollination has led to many natural hybrids and, over the millennia, new species. Plant breeders have followed this example. By careful selection of parent plants we have produced many new varieties and cultivars to grace our gardens. We have also utilised flowers in the kitchen and medicine cupboard. Balms and tinctures can be made from marigolds and arnica. Healing teas can be brewed from chamomile and hibiscus, and perfumes distilled from rose and lavender. Recently there has been a fashion for edible flowers, such as violas and nasturtiums, adding colour and flavour to salads.
Not all flower fragrances can be bottled and sold at the perfume counter of John Lewis. Plants that specifically attract flies tend to smell of rotting meat, these are the carrion or corpse flowers, including the curious Stapelia gigantea and the monstrous Amorphopallus titanum.
The most valuable of all however are the golden stamen of Crocus sativus, the saffron crocus, more expensive by weight than gold!
The second way that plants can be pollinated is by the wind.
The aptly named cruel plant, Araujia sericifera, is a case in point. When a moth inserts its proboscis into the flower it will sometimes hold onto it for several hours to ensure pollination. It does not always end well for the moth.
These are the ones to blame for our seasonal hay fever, caused by an allergic reaction to the pollen laden air. As it is not necessary to attract pollinators they don’t need to produce showy flowers or delicious scents. All they need to do is to ensure their flower spikes are held high enough for the breeze to catch them, to both distribute their pollen and receive the same from another. Yew trees can be seen to produce clouds of pollen from their tiny cones at the merest gust.
The wind as an aid to pollination
Although often a thing of great beauty, the flower’s main role is as a “come hither” to pollinators. And their urge to procreate is relentless. Daphne bholua ‘Jacqueline Postil’
Once pollination has taken place the pollen tunnels its way down into the ovule where fertilisation occurs with the female egg cell. Then the ovum begins to swell, the fruit begins to form... www.countrygardener.co.uk
Vibernum xbodnantese 9
The August 2019 issue of Cornwall Country Gardener Magazine