Both the horticultural industry and gardeners are increasingly interested in new plants to fuel profits, enhance gardens and add to collections. I report on many of them over on my Royal Horticultural Society New Plants blog. But there are few ways to determine how popular new introductions are. Plant producers tend to view their sales figures as trade secrets and there are no countrywide groups collecting statistics.

In Britain the annual publication of the Royal Horticultural Society’s Plant Finder is a useful guide. All the new introductions are marked and it’s easy to count how many nurseries list each. So one guide to popularity is the number of nurseries that list each new introduction. Here are the top eight for this year.

1. Actaea pachypoda ‘Misty Blue’ Blue-tinted foliage marks out this form of the US native, selected at the Mt Cuba Center in Delaware. Read more on my RHS New Plants blog and also here on Transatlantic Gardener.

2. Geranium ‘Midnight Clouds’ (above, click to enlarge) White flowers set against purple-foliage, an uncommon combination, make this one of the standout plants of the year. Read more on my RHS New Plants blog.

3. Erodium ‘Freedom’ A prolific dwarf hybrid erodium from Holland, with prettily dissected foliage and vivid pink flowers. Read more on my RHS New Plants blog.

4. Chasmanthium latifolium ‘River Mist’ (left, click to enlarge) From the Georgia raiser of the Big Sky™ echinaceas, a lovely variegated form of a popular ornamental grass. Read more on my RHS New Plants blog.

5. Echinacea purpurea 'Magnus Superior' The upgrade on the excellent ‘Magus’, the best seed-raised echinacea just got better. Read more on my RHS New Plants blog.

6. Filipendula 'Red Umbrellas' With brightly divided green foliage blazed with deep red, this is attractive from when the leaves first unfurl. Read more on my RHS New Plants blog.

7. Geranium 'Fay Anna' An astonishing combination of red and orange foliage and purple-veined pink flowers.

8. Heuchera 'Magnum' Imposing plant with huge burgundy red leaves up to 10in/25cm across. From Thierry Delabroye.

By the way, notice anything about these eight? They're all perennials... No shrubs, no climbers, no container plants... just perennials.

In all there are 3,508 new entries in the 2011/2012 RHS Plant Finder (up from 3,434 last year) including 237 new irises (199 last year), 210 new primulas (111 last year), most of which are auriculas, 149 new hostas (71 last year) and 131 new dahlias (55 last year). Last year’s leader was hemerocallis with an amazing 400 new arrivals (just 74 this year).