Plant trials: 2011's best buys

Which? Gardening finds out if the new plants in garden centres are worth growing - and picks the best buys for this year's garden
Passiflora 'Perfume Passion'
The multicoloured, complex blooms of Passiflora 'Perfume Passion' are impressive even without the added bonus of its scent
Even at this time of year, there are plenty of tempting new plant varieties for sale in catalogues and online. Which? Gardening has grown them in order to let you know which ones are worth buying.

So, get your orders in now for great plants that will offer plenty of colour later.



The claims: Abundant, exotic flowers with the fragrance of jasmine. Orange fruits in late summer. Doesn’t require very much maintenance, but is tender.

Our verdict: The multicoloured, complex blooms of ‘Perfume Passion’ would have impressed us even without the added bonus of scent. The perfume was a mixture of ginger and lily, rather than jasmine.

With three-pointed leaves and attractive curly tendrils, our plants ranged over their supports. There were rarely several flowers out at once, but there was a steady stream of blooms and each one was stunning. We didn’t get any fruit, though. We placed ours in a large pot and brought it inside before autumn frosts.

Flowering peak: June-October
Height: 160cm
Position: Best to grow in a conservatory or movable container
Price: £6.99
Where to buy: Thompson and Morgan: 0844 248 5383; (delivery by the end of June 2011)
Rating: ****

Mandevilla (Dipladenia) Sundaville Series
Mandevilla (Dipladenia) 'Sundaville Red' grows from a young plant to give masses of pink-red trumpet flowers


The claims: Exotic, trumpet blooms on twining stems. A vigorous climber giving a breathtaking display throughout summer.

Our verdict: We grew ‘Sundaville Red’ from a young plant and enjoyed masses of pink-red trumpet flowers with white highlights. In August, we counted 26 blooms and many more buds. The climbing stems were clothed in healthy, glossy green leaves. As mandevillas are tropical and not hardy, we started our young plant indoors and moved the pot outside in June after the risk of frost had passed.

Flowering peak: June-October
Height: Can grow to 112cm or higher with support
Position: A pot you can move indoors in autumn
Price: £9.99
Where to buy: Cross Common Nursery: 01326 290722; (delivery by the end of April 2011) and Thompson and Morgan: 0844 248 5383;
Rating: *****

Petunia 'Black Velvet'
The new bedding plant for summer 2011? Sophisticated black petunia - Black Velvet - should be grown en masse for the biggest impact


The claims: A novelty flower with wonderful deep-black velvety blooms and luscious green foliage. Compact, suited to growing in containers.

Our verdict: ‘Black Velvet’ flowered all summer long. Most of the large, rich purple-black velvety flowers were plain, but occasionally there were yellow stripes. The bright green foliage showed off the unusual blooms. We grew ‘Black Velvet’ from plugs in a pot, where it stood up to hot weather and rain. Plant it with black lilyturf (Ophiopogon planiscapus ‘Nigrescens’) for a sophisticated display.

Flowering peak: July-September
Height x spread: 51 x 26cm (trails to 29cm)
Position: A pot or border
Price: £7.95 for 5 plugs
Where to buy: Mr Fothergill’s 0845 371 0518 (delivery from the end of April 2011), Unwins 01480 443395 (delivery from May onwards)
Rating: ****

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