Sow the seeds of summer

Recent harsh winters have left gaps in many gardens

Recent harsh winters have left gaps in many gardens. Here's what some of Ireland's leading gardeners are planting from seed to replace the casualties, writes FIONNUALA FALLON

IF THERE'S ONE thing that Irish gardeners can grudgingly thank the bitterly harsh winters of 2009 and 2010 for, it's the devastation that those record low temperatures left in their wake. Because along with the inevitable regret for the loss of so many much-loved plants came the strangely giddy realisation that there was suddenly lots of space to experiment – where for a long time there had been none.

What's more, while those icy frosts and heavy falls of snow may have done for some old favourites, they also did for many of the lame ducks of the garden – those plants that never quite worked because they were too shade-casting, too short-flowering, too gaudy, too dull, too invasive, too demanding, or just too generally unappealing.

The very best gardeners are ruthless executioners when it comes to such undesirables, but not so the rest of us, which is why many felt a strange sneaking gratitude for the ruthless horticultural de-cluttering that was an indirect result of the big freeze.

But where to begin and what to choose when it comes to filling those newly-opened gaps in the garden? For the widest choice, as well as economy of scale, nothing beats growing new plants from seed, and right now is the time to start placing orders.

Here, by way of inspiration, are a few of the more unusual flowering and foliage plants that some of the country's best-known and most expert gardeners are planning to grow this year, as well as a list of their favourite seed suppliers.

For Neil Porteous, the newly appointed head gardener in charge of the restoration of the magical, world-renowned Mount Stewart gardens in Co Down, this will be the year to experiment with a range of tender or marginally hardy exotic trees, shrubs, annuals, biennials and perennials, with seeds sourced both from Jungle Seeds and Chiltern Seeds. His 2012 order includes the lovely, pink-flowering silk tree, Albizia julibrissin rosea; the 'Poor Man's Orchid', Schizanthus pinnatus; the spectacular Calliandra haematocephala; and the oleander Nerium oleander. "We have a special microclimate here so we will be growing plants not often grown outside," says Porteous, adding that on the south-facing slopes of the garden, "we will be planting bigger annuals or biennials: Datura metelloides, Ricinus communis 'Gibsonii', Calomeria amaranthoides and Nicotiana sylvestris 'Only The Lonely'.

Another Irish garden now under skilful restoration is the walled garden at Russborough in Co Wicklow that the RHSI recently took under its wing, headed up by a team that includes the distinguished horticulturist Anne James. Given the limited budget available to the society as well as the large scale of the project, almost all of the plants used at Russborough will be propagated from cuttings or from seed.

"While we haven't finalised the complete seed order, I'll definitely be ordering seed of the lovely annual, Ricinus communis 'Carmencita' for its striking red foliage and its usefulness as a specimen container plant. Another favourite is the tender purple-bell vine, Rhodochiton atrasanguineum, while for a shady border and for something different, I'll also be ordering the perennial Tacca nivea," says James. All are from Thompson Morgan, while the society will also be sourcing heritage varieties from Thomas Etty.

For one of Ireland's best-known gardeners, Helen Dillon, this year offers the opportunity to replace some old favourites including the wonderfully handsome spiral aloe, Aloe polyphylla "which was killed last winter but flowered magnificently in summer 2010" and Tropaeolum tricolorum – "a very pretty early spring greenhouse climber, with remarkably flashy, black and orange-red little flowers" – that grew in the Dillon garden some years ago (both from Chiltern Seeds).

Another favourite is the very lovely white-flowering perennial, Selinum wallichianum – 'queen of the umbellifers' – fresh seed of which she'll be sourcing from Derry Watkins of Special Plants.

Rather than paying, there are also some wonderful ways to source seed for free, as Philip Havercroft of the Wicklow-based Leamore Nursery explains: "Membership of the Hardy Plants Society (HPS), the RHS, or the Irish Garden Plants Society (IGPS) entitles you to a share of the seed collected by members. It's a fantastic way to source seed of some rare or unusual plants that wouldn't otherwise be available."

The man in charge of the 2012 IGPS seed list is Stephen Butler, who's also the head gardener at Dublin Zoo. "The Irish Garden Plant Society distributes a seed list to members each January, with a varied selection of garden plants. Out of this year's total of 214, there are 52 bulbs (12 species of Allium, 4 of Fritillaria), unusual climbers such as Dactylicapnos scandens (a climbing form of Dicentra), wonderful shrubs such as Decaisnea fargesii with purple, sausage-sized seed pods, and many herbaceous plants, including Datisca cannabina, a cannabis lookalike that may cause you grief," says Butler.

If you particularly like the idea of sourcing Irish-grown seed, then take a look at the reasonably-priced list available from Jimi Blake, which includes fresh seed of herbaceous perennials, tender perennials, annuals, biennials, grasses, shrubs and trees – all of which have been collected in his Wicklow garden, Hunting Brook.

Sibling gardener and nursery-owner June Blake also strongly recommends Jelitto Seeds, in particular the long-flowering and deliciously scented perennial, Agastache 'Sangria' ("so easy from seed"), the very early-flowering Lathyrus vernus 'Rosenelfe' ("the most beautiful pink flowers"), and perennials Knautia arvensis and Knautia macedonica, intermixed. "Let run riot, they will self-seed and produce flowers in the loveliest mixture of colours and heights."

Mmmm. Tempted? I know I am

Diary date.

The annual Garden and Landscape Designers Association (GLDA) seminar will be held next Saturday, January 28th at the Botanic Gardens in Glasnevin, Dublin. The title of this year's seminar is Biodiversity and Sustainability in Design – Isn't that the Question?

Key speakers will include Dr Matthew Jebb of the National Botanic Gardens, the American author, photographer and horticulturist Rick Darke, and Phil Askew, landscape architect for the Olympic Development Association.

For tickets and further information, please contact the GLDA. Tel: 01-2940092, or see glda.ie

Seed sources