The sealed bottle garden still thriving after 40 years without fresh air or water

 To look at this flourishing mass of plant life you’d think David Latimer was a green-fingered genius.

Truth be told, however, his bottle garden – now almost in its 53rd year – hasn’t taken up much of his time.

In fact, on the last occasion he watered it Ted Heath was Prime Minister and Richard Nixon was in the White House.

For the last 40 years it has been completely sealed from the outside world. But the indoor variety of spiderworts (or Tradescantia, to give the plant species its scientific Latin name) within has thrived, filling its globular bottle home with healthy foliage.

Yesterday Mr Latimer, 80, said: ‘It’s 6ft from a window so gets a bit of sunlight. It grows towards the light so it gets turned round every so often so it grows evenly.

‘Otherwise, it’s the definition of low-maintenance. I’ve never pruned it, it just seems to have grown to the limits of the bottle.’

The bottle garden has created its own miniature ecosystem. Despite being cut off from the outside world, because it is still absorbing light it can photosynthesise, the process by which plants convert sunlight into the energy they need to grow.

Photosynthesis creates oxygen and also puts more moisture in the air. The moisture builds up inside the bottle and ‘rains’ back down on the plant.

The leaves it drops rot at the bottom of the bottle, creating the carbon dioxide also needed for photosynthesis and nutrients which it absorbs through its roots.

It was Easter Sunday 1960 when Mr Latimer thought it would be fun to start a bottle garden ‘out of idle curiosity’.

He said: ‘At the time the chemical industry had changed to transporting things in plastic bottles so there were a lot of glass ones on the market.

‘Bottle gardens were a bit of a craze and I wanted to see what happened if you bunged the thing up.’

Into a cleaned out ten gallon carboy, or globular bottle, which once contained sulphuric acid, he poured some compost then carefully lowered in a seedling using a piece of wire.

He put in about a quarter of a pint of water. It was not until 1972 that he gave it another ‘drink’.

After that, he greased the bung so it wedged in tightly... and has not watered it since.

The bottle stands on display under the stairs in the hallway of his home in Cranleigh, Surrey, the same spot it has occupied for 27 years after he and his wife Gretchen moved from Lancashire when he retired as an electrical engineer.

It was revealed to the world when he took a photograph of it in to BBC Radio 4’s Gardeners’ Question Time and asked the panel of experts if it is ‘of scientific or horticultural interest’.

Garden designer and television presenter Chris Beardshaw said: ‘It’s a great example of the way in which a plant is able to recycle... It’s the perfect cycle of life.’

He added that this process is one reason why NASA was interested in taking plants into space.

‘Plants operate as very good scrubbers, taking out pollutants in the air, so that a space station can effectively become self-sustaining,’ he said. ‘This is a great example of just how pioneering plants are and how they will persist given the opportunity.

‘The only input to this whole process has been solar energy, that’s the thing it has needed to keep it going. Everything else, every other thing in there has been recycled. That’s fantastic.’

Organic gardener Bob Flowerdew was less enthusiastic.

‘It’s wonderful but not for me, thanks. I can’t see the point. I can’t smell it, I can’t eat it,’ he said. Mr

Latimer agrees the bottle garden is ‘incredibly dull in that it doesn’t do anything’, but remains fascinated to see how long it will last.

He hopes to pass on the ‘experiment’ to his grown-up children after he is gone.

If they do not want it, he will leave it to the Royal Horticultural Society.