Three of Everything Please /
Growing trilliums has become a gentle obsession for an Ashburton couple
Growing trilliums has become a gentle obsession for an Ashburton couple, who
discovered these beautiful woodland perennials 15 years ago.
As the botanical name suggests, trilliums have many of their structures arranged in threes – ‘tri’ from
Latin and Greek meaning three – and multiples of three. Their leaves (actually green bracts, and often beautifully patterned), leaf veins, petals, and even tiny flower parts such as stamens and ovary capsules are formed in threes and sixes. Some species have an almost poetic beauty, some are pleasantly scented, and trilliums can range in height from five to 50 cm. Distantly related to lilies, the Trillium genus is native to temperate areas of the northern hemisphere, with the majority – approximately 45 species – from North America, and the remainder from Japan, China and Korea, Eastern Russia and the Himalayas. In protected areas of the Appalachian Mountains along the famous Blue Ridge Parkway, there’s a spectacular spring flowering of wild trilliums under native deciduous woodlands of dogwoods and magnolias. Whole hillsides of pale pink, lemon and cream blooms complemented by hints of fresh green foliage stand with drifts of trilliums around their trunks in a similar range of colours, with clumps of wine-red here and there.
Ashburton couple Ian and Janene have been developing the garden at their home just south of the highway bridge since 1994. When they first bought the house, an existing garden of mainly conifers and shrubs was not entirely to their taste – with the exception of a fine ‘Meyer’ lemon on a sunny wall. Now well established, the tree provides plenty of fruit, with any surplus enjoyed by grateful family and friends. Soil conditions were a challenge; Janene remembers, ‘We had to
dig out and break up the clay base, building the soil structure by adding vermicast (a mixture of earthworm castings and uneaten bedding and feedstock harvested from worm beds) from the local abattoirs, plus compost.’
Once soil and drainage had been improved, the couple could focus on the kinds of plants they loved. ‘We planted rhododendrons, camellias, maples and roses, after many trips to various garden centres and nurseries around the South Island.’ And under these taller shrubs and trees a lower layer of planting could be established, protected by the increasing shade and shelter.
Ian and Janene grew other herbaceous perennials, but were unfamiliar with trilliums until they saw one blooming in a friend’s garden 15 years ago. They bought their first plant ‘and from then we were hooked, and travelled many a mile to buy various species after reading gardening advertisements and attending the Alpine Garden Society Spring Shows in Christchurch’. They would not like to estimate the dollars spent on trilliums!
Trilliums’ natural habitat is mostly under trees – not just deciduous woodland as we’ve seen in Eastern North America, but in old-growth Coast Redwood Sequoia sempervirens forests in California for example, where Trillium ovatum forms colonies among the massive trunks. Trilliums typically like leafy open soils with good drainage which do not become too dry, and, as specialist grower and Christchurch gardener E. Gay Henderson notes in Trilliums for your Garden, ‘a cool woodland or shady area, and a cold winter rest. They need
plenty of light in the early spring but shade as the summer becomes hot. Deciduous trees suit trilliums well, by providing shade in summer, leaf cover on the floor of the woodland in winter, and allowing light when it is required in the spring’. She also describes the two basic groups of species: those whose flowers have stalks (pedicel) and those whose flowers sit directly on the leaves (sessile). Trilliums are a promiscuous bunch, hybridising easily and making identification somewhat tricky.
Ian and Janene have found that in their garden on moisture retentive soil the plants prefer dry feet, a good layer of mulch, and half a day of sun (if they’re growing in the open). Trilliums can be lifted and divided in mid-late January if needed, after the leaves have died down and seed heads have formed. They grow from rhizomes, and once these are out of the ground it’s vital to keep them cool and damp. I’ve found it best to gently separate and pull the clumps apart by hand or with a blunt trowel; and cleanly sever side shoots with a sharp knife, as they are delicate and can be easily cut or bruised by a spade or fork.
After growing trilliums for a few years, the couple were clearly having great success, because on a Sunday morning in 2008 a local member of the New Zealand Trillium Group knocked on the door and ‘asked if we might open our garden to the group who were holding their annual weekend gathering in Ashburton and Christchurch. And that was how we joined the NZTG. After visiting many beautiful gardens and purchasing plants from members’ sales tables, after 11 years with the group one soon realises that there is so much more to trilliums than red, yellow and white! We now grow close to 30 different species and have over 100 plants – just some of our favourites are T. grandiflorum (double-flowered form), luteum, flexipes, erectum and vaseyi’.
E. Gay Henderson (who originally recommended me to Ian and Janene) encouraged the couple to start growing trilliums from seed, and even though they can take five or six years to flower by this method, Ian and Janene have succeeded with some lovely specimens which are now planted out in the garden.
I have some trilliums in my own garden, mainly the well-known T. chloropetalum which forms generous clumps
‘We now grow close to 30 different species and have over 100 plants.’
nearly 40 cm tall in a good year. Many of these trilliums are divisions or seedlings from friends’ gardens in Christchurch – in particular Mrs Barbara ‘Micki’ Kerr, and Mrs Alison Ayling – whose maple and dogwood trees provided the ideal light shade, and whose trilliums associated so well with their superb collections of species rhododendrons. Trilliums can be long-lived plants, and two clumps of Micki’s trilliums are special favourites: one creamy white and the other dark winered, both now over 50 years old and which moved with her from Timaru via horse float, to two other gardens she created in Christchurch. In Alison’s garden we noticed in recent years that trilliums were producing more seedlings – possibly responding to our milder winters.
Trilliums associate very well with rhododendrons, Himalayan Daphne D. bholua, dogstooth violets Erythronium, hellebores, primulas, and naturalised spring bulbs such as snowdrops Galanthus, all of which enjoy conditions under deciduous trees, and flower during the same period. Ian and Janene have planted a variety of daffodils Narcissus and spring-flowering perennials with their trilliums, sourced through mail orders and Pleasant Valley Daffodils in Geraldine.
There’s a knack to assembling a group of plants to show the trilliums at their best when they’re in flower, and then conceal their spent leaves through the summer. This sequence of growth is vital in a smaller garden space, beside floor to ceiling doors and windows looking out into the garden. A version of this in my own garden has worked well so far. Along the (shingle) driveway in a shady border is planted a line of pale yellow-flowered epimediums, E. sulphureum versicolor; tough evergreen woodland perennials. Behind these are groups of trilliums with the spaces between groups planted with the medium-sized blue/green-leaved Hosta ‘Halcyon’ and white Astilbe. Michelia yunnanensis ‘Gracipes’ provides overhead shade.
Beginning in mid-winter, the epimedium leaves are removed to ground level, before the flower buds start to extend. These open up to 30 cm sprays of yellow flowers in mid-September, slightly ahead of the trilliums. By late
Trilliums are one of the most attractive woodland perennials available to gardeners, and will grow happily with a little attention to conditions.
September the trilliums are in full flower, and new coppercoloured epimedium leaves are rising in front of them. Six weeks later when the trilliums are tiring, the epimediums’ green summer foliage fills the front of the garden, and the trilliums have disappeared under hosta and astilbe foliage – these both flower later, as an added bonus. The garden looks presentable until May, when fat resting trillium shoots have emerged above the soil and their old leaves are long gone. All but the epimediums can now be cut back and left to break down, and the garden is lightly fed and mulched with sheep pellets, compost and leaf litter. The soil here is light and sandy – easy to work with, but needing regular feeding, plus organic matter to help retain moisture.
It was a pleasure to meet Ian and Janene when I visited at trillium time, to share in their enthusiasm and hear about their favourite plants. ‘We particularly enjoy the trilliums because of how the different species bloom at different times, spreading the flowering season over two months or more.’Trilliums are one of the most attractive woodland perennials available to gardeners, and will grow happily with a little attention to conditions. Three cheers are particularly appropriate for these beautiful plants.