Chelsea Flower Show 2018: Plant of the year revealed - but is it a winner?

How do you pick the best new plant of the year in May? Well, the RHS takes a good stab at it at every year at the Chelsea Flower Show with its Plant of The Year competition in which new varieties never before seen at a flower show compete for the top award. 

This year’s clear winner is Hydrangea Runaway Bride Snow White (Thompson & Morgan) whose pure white lacecaps open all the way along the stems. In second place was a dramatic new Eryngium hybrid ‘Blue Waves’ (Hillier Garden centres), whose blue flowers repeatedly overtop each other as the flower head branches and spreads widely. In third place was Helianthus Sunbelievable Brown Eyed Girl (Thompson & Morgan) , a spectacularly prolific annual sunflower - that can only be raised from cuttings. 

But here’s the thing: plants are forced for the competition, plants are held back, and if the individual plant entered doesn’t look good for two days just before the show it won’t win – no matter how well it performs through the whole summer. 

The winning hydrangea looked superb, no doubt about it. But in a few short weeks its flowers will fade and we must take the nursery’s word for the fact that it will flower again. The eryngium will flower for many weeks, we can see that individual flowers are long lasting and we can see the many buds developing below. Former Gardeners’ World presenter and veteran garden writer Peter Seabrook had the opportunity to grow the sunflower last year and reports that it flowered from March to December. So which is the true Plant of The Year?

And how much can we rely on the information provided by the people entering the plants? The hybrid digitalis that won in 2012 was said to be hardy but this winter I gave mine the right conditions and they all died, as they have for most people over the years. It’s superb in a large container, though, I have to say. 

In 2013 Mahonia ‘Soft Caress’ won the award, in spite of its flowers not opening until months after the show. The judges trusted the information provided and, in the end, it’s proved to be a fine new shrub. Last year’s mulberry was said to have an excellent flavour, but when I tasted the fruits later in the summer they turned out to have very little flavour – and then pigeons ate all the not-quite-ripe ones! 

So, what about this year? In total, 39 entries were accepted. A few were then withdrawn and some entries failed to make the shortlist simply because the specimens entered were so poor. The verbena with three or four half-open flower heads, the impatiens with hardly a flower to be seen. The iris with no flowers open at all. The calibrachoa that’s such a good plant that it won the People’s Choice award at the RHS Garden at Wisley last year got hardly a look-in because the plants entered for judging were a mess. What’s the point? 

It’s a shame, I saw the verbena flowering last summer and it was superb, and beautifully scented. But from the plants entered, you’d never know. And the impatiens is a breakthrough mildew-resistant variety, a plant so many gardeners have been waiting for. Looking so poor, it was hardly considered. 

Some people entering the plants are missing another trick. Each plant is given just 90 seconds for its presentation so we don’t need to hear, as we did this year, how the presenter is only up there because he married the breeder’s daughter or because his boss had something more important to do. Tell us about the plant! 

Edibles pose a special problem. We didn’t get to taste the mulberry last year, if we had then it may not have won. We were able to taste the ‘Just Add Cream’ strawberry but, having been forced, the fruits were nowhere near as full of flavour as the ones I’d tasted the previous August. 

This year both the pepper ‘Lemon Dream’ and the tomato ‘Shimmer’ could be sampled at the shortlisting meeting, although the ever diligent Plant of The Year supremo Jill Ottway had to dash across the Great Pavilion to collect some - they had not been provided. 

There’s one more problem that breeders and nurseries entering plants should all think about: availability. Pheasant Acre Plants tell me they sold 250,000 corms of Gladiolus ‘Prima Verde’ when it was shortlisted in 2015 and it never even made the top three. So the publicity really can give sales a boost. 

True, nurseries are getting better. Thompson & Morgan have 10,000 plants of their sunflower available this year and 5,000 plants of Hydrangea Runaway Bride Snow White. 6,000 plants of Eryngium ‘Blue Waves’ are available and 7,000 of the sparkling Dahlia Lubega Power Tricolor. 

But only 200 plants of the new variegated Polemonium ‘Kaleidoscope’ are available, a “limited number” of the very appealing dwarf variegated phormium, and no plants at all of the very attractive and nicely scented Viola ‘Bridie’. Wait a year, propagate more, and make the most of the publicity that even shortlisting can bring. 

And what did I vote for? A large and beautiful specimen of Hydrangea Gold Rush was entered, furnished with lovely fiery gold foliage. By August the leaves will turn green to provide the ideal background for the large purple-centred white lacecaps. And then there’s autumn leaf colour and shaggy winter bark! Sounds like a Plant of the Year to me.