Sunny days and a light breeze can mean hell in the garden if you suffer from hay fever
One of the more nerve-racking moments of my schooldays was watching my classmate Sara, who was playing Esther, the plucky Jewish queen, in Mandy Delamer's and my adaptation of the biblical story. Our leading lady suffered from hay fever of fabulous proportions, and our script required that she process regally across a stage piled high with cut flowers. We feared the worst on the big night, but - hallelujah - there were no sneezes or unseemly sniffles, not even a watery eye. The scene was a triumph, played with the powerful dignity that only a 12-year-old can muster.
If I had known then what I know now, our entire class could have been saved huge amounts of stress as we wondered if our Esther's nose would explode. Almost all hay fever, I've since learned, is an allergic reaction to tree and grass pollen rather than to that of ornamental flowers.
Trees are the first to release their pollen, sometimes as early as February - with birch and oak being among the worst culprits (alder, hazel, hornbeam, pine, plane, poplar and willow are also to blame). Grasses follow, from around May until September, with the highest concentrations of their pollen floating around in midsummer. Grasses and most trees are wind pollinated, meaning that the only way the fine grains of powder containing the male gametes (or sperm cells) can meet the necessary female plant parts is through a largely hit-or-miss operation. Therefore, anemophilous plants (which means, literally, "wind-loving" plants) must produce prodigious quantities of lightweight pollen that can be wafted considerable distances.
For those who suffer from seasonal allergic rhinitis, or hay fever, these airborne drifts of pollen cause uncomfortable symptoms to flare up. Sunny days (which encourage flowers to release their pollen) with a light breeze can be hell in the garden for some unlucky people.
Grasses and trees aren't the only offenders. Some "weeds" - or native plants, if you will - are also significant producers of fine, wind-carried pollen. Among them are dock, fat hen, mugwort, nettles, plantain and ragweed. All have fairly unshowy flowers, and are unattractive to insects.
Brightly coloured, nectar-producing blooms, on the other hand, are magnets for insects. Their pollen is easily transported from flower to flower by all manner of invertebrate, including bees, butterflies, beetles, flies, wasps, moths and ants. It is sticky, so it adheres to its insect transporter, and is heavy enough so that it is not easily whisked away by the wind. It is also produced in smaller quantities, as its transference is a carefully planned and economical exercise rather than a random and wasteful event, as with wind pollination.
About 90 per cent of plants are insect pollinated (or entomophilous, if you want to be highbrow about it). This is good news for most hay-fever sufferers. By choosing only plants that are pollinated by insects, you can cut down on the amount of stray pollen flying up noses and mouths, and into eyes - and drastically reduce chances of allergies being detonated. Double flowers (those with lots of extra petals) are often free of pollen, as are big blowsy tuberous begonias. So a gorgeous garden filled with flowers is entirely possible - if you shy away from certain trees, keep the weeds down and ban ornamental grasses. But what of the lawn? Surprisingly, a lawn can trap pollen. In a garden filled with hard surfaces, such as concrete, slabs or even buildings, pollen is less likely to settle, and may blow around, remaining a continuing source of havoc. With a good, thick lawn, however, the grains are trapped by the blades of grass, and eventually washed onto the soil, where they decompose. If the grass is regularly cut, it won't flower. Using a grass-collector on the mower ensures that stray pollen is kept to a minimum. All the same, if you are the allergic one in the house, get someone else to do the mowing.
And now a bit of necessary botany. As I mentioned earlier, pollen grains, the guilty parties in this hay-fever business, are part of the male reproductive system. Plants come in many sexual configurations: some bear flowers of a single sex (and are known as dioecious, Greek for "two houses"), others bear male flowers and female flowers on the same plant (monoecious, "one house"). Still others are hermaphroditic; that is, they have organs of both sexes in the same flower, which is then described as a "perfect" flower. Such plants are also known as monoclinous, which means "one bed".
Hay-fever victims should take note of the above paragraph, because it holds the key to relief. Dioecious (single sex) plants of the male persuasion - poplar and willow, for instance - are the worst for scatter-shooting volleys of pollen. The male flowers on monoecious plants (birch and oak) are almost as bad. The least promiscuous are hermaphrodite plants, with their "perfect" flowers.
In the case of someone who is extremely allergic to pollen, then the ideal garden is one with non-flowering, non-pollen-producing and single-sex plants of the female gender. In other words, when it comes to hay fever and plants, it's the male of the species that causes all the aggravation.