Some plants last centuries. Others are fleeting, writes Deirdre Black
This year is the 40th anniversary of a ground-breaking artwork in lower Manhattan. Alan Sonfist's Time Landscape, at the intersection of West Houston Street and LaGuardia Place, is a 750sq m island of indigenous Manhattan forest in the heart of high-rise, high-octane New York. The urban mini-forest is a revival of the natural environment that existed before the city grew skywards, in the 19th century.
Closer to home, a contemporary public park in Co Meath, due to begin construction this year, will reinterpret in its design the ubiquitous and dynamic Irish patchwork of field and hedgerow. Modern features such as skate parks, football pitches and playgrounds will be arranged in a layout inspired by the centuries-old pattern of the rural landscape.
Both these schemes investigate the relationship between landscape, the passing of time and the role of society in this process. Any landscape is transient by nature, the tempo of change always conducted to a geological, lunar and solar beat. Only sometimes is the rhythmic baton taken up by society. If you take heed of Einstein, or many of the world's religions, poets and musicians, this human sense of time is elastic. The stretching, contraction and circling of time seems closer to the truth than the apparently regular tick-tock of linearity. No end of poetry has taken flight in expression of seconds as eternities and lifetimes as moments.
To the human observer, then, passing cloudscapes are as much a part of the temporal landscape as the stoic and dignified pseudo- permanence of ancient trees. Permanence, to be truthful, can only ever be experienced in a moment, as all experiences are what Simone de Beauvoir called "a splendid immediacy - those moments of respite when suddenly time stands still and one's existence blends into the unmoving fullness of the universe".
In the splendid immediacy of your garden, the ephemerals are the plants to fuel these transient dreamings - annuals, biennials and short-lived perennials that live fast and die young. These plants, and their gorgeous groupies the butterflies, strut their outrageous young beauty at this time of year and laugh in the face of longevity. This summer zenith would seem the appropriate point to, as Patrick Kavanagh wrote, "snatch out of time the passionate transitory".
But perhaps your mood is a little more country, a little less rock'n'roll. Ephemera are all well and good, but where's the long-term payback? You'd rather, like Blake, "hold infinity in the palm of your hand, and eternity in an hour". You need a tree, a long-lived tree, a tree your great-great-great-great-grandchildren will carve their names on. Although this is not the best time of the year for planting trees, if you make sure to water it well over the coming months you too can make your arboreal claim on the future.
New York's out-of-time forest illustrates with some blatancy the play-off between human and natural processes. Now that the replanted trees are reaching some maturity, the space can be read as a patch of everlasting Eden that stayed still while the skyscraping city rose around it.
Andy Warhol's legendary eight-hour, one-shot film of the top of the Empire State Building strikes a different note. Nothing changes on the screen - the building certainly doesn't move, and there are no people - but then you notice that everything is changing: fluctuating cloudscapes, lengthening shadows and the ever so gradually fading light lay bare our beautiful insignificance in the self-winding tick-tock of transient time.
As Plutarch put it: "The whole life of man is but a point of time; let us enjoy it."