I HAVE been enjoying the snowdrops in my Staffordshire garden for a few weeks, and now the first crocus is emerging. Both have an inherent delicate beauty that is worthy of close observation, and is at odds with the cruel February weather. If I am honest, though, I love them just as much as harbingers of longer days and warmth.

In a similar way, some plants have such strong associations with sunlight, blue skies, and balminess that they can uplift and transport us. Foremost of these, for me, is the olive tree. Ten to 15 years ago, they were readily available; so now there are sizeable outdoor specimens in London. Walking amid the corporate splendour of the City, or along a row of suburban front gardens, I suddenly witness the flash of silver as a cold breeze catches the branches in a shaft of pale winter sun, and I am back on the Greek island of Spetses, where I pruned row upon row of young olive trees looking up into the blue.

In Staffordshire, at the garden centre, a potted olive beckons. Is this an unwise impulse? Gardening should be about matching plants to environment so that they thrive without too much cajoling. But then gardening is also about manipulation, and the geography of my patch has many microclimates, including a south-facing slope in the lee of the garage on free draining sandy sub-soil.

The natural habitat of Olea europaea defines the Mediterranean region for botanists: essentially a narrow coastal strip surrounding the sea of that name. Some models of global warming predict that this will extend northwards, and British growers have for some time been emboldened to experiment. The winter of 2010/11 made us question the wisdom of this.

Olives are reasonably hardy: mature plants are able to withstand frosts down to -10°C. At the Chelsea Physic Garden, a mature tree flowers in early summer, its myriad small creamy blooms dusting the paths with pollen, and crops in autumn after a hot summer. The olive fruit are harvested green before the wood pigeons can steal them.

For most of us, the answer is pot culture. Use a loam-based compost with 20 per cent added grit to improve drainage. The container needs to be large, but bear in mind that it needs placing outdoors in summer, and in a frost-free greenhouse in winter. Don't cosset the plants too much in winter, as production of the wind-pollinated self-fertile flowers will be inhibited by warmth above 15°C as effectively as by prolonged severe cold.

Lacking a greenhouse, I am determined to grow a tree in the open ground. The solution may lie in a cultivar called "Veronique", which purports to be hardy down to -20°C, and to produce a reasonable crop in most British summers. With the right genes, it may just give me the sunny fix I crave.

And if I do get caught out in a winter to come, all may not be lost. The remarkable regenerative powers that enabled olives all over the Peloponnese to rise, phoenix-like, after the forest fires in 2007, work just as well after a killer frost.