THE air has become infused with a selection of heavy, heady pungent scents, which intensify on the warming morning thermals. It is a mixture of sweet toffee and honey, and initially took me some time to identify. I wandered around scanning the ground for some colourful flower.

The field of oil-seed rape just one hundred yards away had almost turned dazzling yellow, but this was a more musky smell than that of the golden brassica.

At this moment a small flock of goldfinches burst out from the stand of teasels by the side of the path.

You can almost guarantee the arrival of these stunning birds by growing even just a few teasels.

They feed on the thistle-like seeds throughout the winter and drink from the cups that form at the joining of stem and leaf. I watched them as they flew past me, dipping and chirping. They fluttered through the leaves of a tall slim tree, whose leaves where twinkling in the rising spring sunshine.

My attention turned from the birds to the tree. It was one of those trees that you always see, but never really notice. They are rarely grown as single specimens, but usually in long, linear rows as wind breaks or shelter belts. A slight breeze ruffled through the foliage and brushed passed my face. The toasted honey scent landed in front of my nose. It was the smell of the newly emerged balsam poplar leaves.

The poplar is a deciduous tree that is native to Europe. There are many varieties, almost too many to classify, as they readily to hybridise with each other. It prefers open and exposed areas and thrives particularly well on poor soil. One of the most common poplars, the aspen (populus tremula) has leaves that tremble in the slightest breeze. The old Anglo-Saxon word for tremulous was 'aespe', which is how the tree attained its name. You very often see them planted by the side of the road or on motorway embankments.

This is because they are quick to grow, have non invasive root systems and can cope with large amounts of pollutants in the atmosphere (car exhaust fumes). In fact, the leaves help to filter out some of the chemicals and act as a sound buffer by absorbing a certain amount of noise.

The wood from the poplar is of considerable commercial value. It is better than any other wood at resisting fire and for this reason shiploads of aspen logs were imported annually from Finland for the manufacture of matches, match boxes, fruit and flower boxes. It was also the wood used to make brake blocks. Today, it mainly gets used as flooring material, because it can withstand large amounts of friction before catching fire.

It is another poplar, the balsam poplar (populus balsmifera) that releases the powerful musky scent.

This comes from their emerging leaves. A traditional cure-all balm used to be made from its resin, and the buds were made into a hair wash. The leaves were used in herbal remedy for gout and rheumatism, and as a compress, a treatment for burns and haemorrhoids.

For a tree that goes largely unnoticed, it has a proved to be an immensely useful one. It only blows its cover once a year when it fills the air with its wonderful sweet resinous aroma.

JOBS THIS WEEK

Plant out brassicas, but remember to fit a carpet or cardboard collar around the base of the stem to prevent invasion by cabbage root fly.

Pull out any weeds growing amongst sown seedlings. It may take a little time to familiarise yourself with the seedling and distinguish it from any rogue weeds.

Tie in climbing roses as they start to shoot away. The more horizontal you can get the main stems, the more growth and flowers you will get later in the year.

READER'S QUESTION

MR Gresham wrote to ask if it would be possible to grow melons in his greenhouse this year. He would love the challenge of growing something other than tomatoes and courgettes this summer.

THE melon is a tender plant, which belongs to the same family as the cucumber, Cucurbitaceae. It is a native of Asiatic countries and has long been grown in this country.

For a summer crop, the seeds should be sown under cover in April or early May. Ideally, they prefer a temperature of 50-60 degrees. The seeds should be sown in individual pots, one inch under a light loamy compost. They should be sown on their edge (and not laid flat) to prevent them rotting. The old method was to plunge the pots into a bed of hot manure, but today a heated greenhouse will do the same job. Do not overwater them as they will not germinate in sodden soil.

Once the seeds have germinated, prick them out and grow them on in the greenhouse up a wire mesh or trellis. Do not pinch out the tips until they reach the top of their support. Tie in any side shoots which develop from this main stem.

This is where the flowers and fruit will form. Pollinate the female flowers (the ones with a swelling at the base) by pulling off a male one and rubbing it over the female. Keep the greenhouse dry and aired during pollination, but once the fruit begins to develop, they need a warm, moist atmosphere. Do not let the soil dry out. Support the fruit as it swells by tying with raffia or holding in an old pair of tights.

Brigid presents Ask About Gardening every Sunday on BBC Radio Cleveland from 12-2pm, and works at Nature's World in Middlesbrough during the week.

Send your questions to be answered in The Northern Echo to Brigid at brigidpress@hotmail. com or write to her c/o Nature's World, Ladgate Lane, Acklam, Middlesbrough.

Published: 01/05/2004