The Chelsea Flower Show: pick of the bunch

The Most Spiky Garden: Kirstenbosch National Botanical Garden

How will climate change affect us? Will it be colder, or warmer, or wetter or drier? In South Africa, judging by this exhibit, which demonstrates the early warning signs of the impact of global warming on what should be a lush landscape, one thing is for sure. It's going to be pricklier.

The Most A-list Garden: from life to life, a Garden for George

Preview day at Chelsea is a bit of a celebfest, so you need to be pretty A-list to cause a stir. And it seems you can't get more A-list than Ringo Starr. He arrived to see the garden sponsored by George Harrison's charitable trust in a Mini driven by Damon Hill. Cue lots of posh ladies screaming "Ringo, Ringo!"

The Most Alarming Garden: The Royal College of Pathologists and the Health Production Agency

This exhibit looks at how malaria, eliminated from the UK by the 20th century, may return thanks to climate change and our growing fondness for al fresco living. Be afraid, be very afraid.

The Greenest Garden: The Laurent-Perrier garden

Tom Stuart-Smith says this design is his antidote to Chelsea – an attitude as refreshing as his verdant garden. It's a brave move to go for something so monochromatic when the public and TV crews love a bit of colour. But given his string of gold medals and awards, perhaps he's just ahead of the crowd. Let's hope that he's rewarded for, as the poet Andrew Marvell put it, "annihilating all that's made to a green thought in a green shade".

Most typically tropical garden: Queen Elizabeth II Tropical Garden, Cayman Islands

A little cottage with roses round the door evokes images of home. And better still, it's in the Caribbean! This ultimate of downsizing fantasies is intended to enable visitors to "imagine the warm Caribbean breezes as they rustle the coconut fronds overhead, while all around the bold foliage and vibrant colours evoke a feeling of tropical exoticism". Well, it certainly does the trick for us.

Most Sporting Garden: Cardiff City Council

Why build a giant rugby player from plants? To promote the Welsh city as a Capital for Sport, of course. They're trumpeting the hosting of the Ashes in 2009, the Ryder Cup in 2010 and Olympic football in 2012. Just don't mention the FA Cup final.

The Most Caffeinated Garden: The Oceanico garden

Designed by Diarmuid Gavin and Sir Terence Conran, this is a marriage of food and flora. It features a coffee shop and the services of Branko, one of London's best baristas, whose normal stamping grounds are The Dorchester or Marco Pierre White. The planting features box balls interspersed with herbs and purple alliums, and grasses that are as fluffy as the froth on a cappucino.

The Most Subterranean Garden: I Dream, I Seek My Garden

This vertiginous garden, designed by the Chinese artist Shao Fan, is a Chelsea record-breaker. It's the deepest garden ever built at the show, and it contains the highest wall, which is perhaps appropriate as it deals with a big subject: the economic transformation of China and the potential loss of its culture. Watching television presenters gingerly crossing the stepping stones provided the best fun of the show.

The Most Child-Friendly Garden: The Marshalls Garden That Kids Really Want!

It may seem rather ironic that a company known for providing hard landscaping for the nation’s drives and patios should be doing a child-friendly garden. But Ian Dexter’s design really works, and exhaustive consultations with primary-school children have resulted in something that is pretty close to the ultimate childhood fantasy, with a tunnel, a cave, a pond and dinosaur-type plants.