Few months in the gardening year are more joyful than April with its oh-so-pretty froth of flowers and newborn greenery.
It is the gardening month most filled with possibilities and the promise of new beginnings, the one that shuts the door on winter and ushers in spring with a happy holler of delight. It gives us swathes of tulips with silky, colourful blooms atop tall, slender stems and armfuls of deeply scented, pale-flowered narcissi. Drifts of sky-blue forget-me-nots too, and clouds of cherry blossom as well as purple-belled tangles of clematis draped against old garden walls and woodlands filled with the sweet smell of wild bluebells. Plus – that sweetest of spring sounds – the ponderous hum of queen bumble-bees freshly emerged from hibernation, diligently foraging for food amid the pollinator-friendly blooms of wallflowers, honesty, lungwort, berberis and flowering currant.
Here’s a celebratory look at 10 of the loveliest April-flowering plants for the Irish garden.
1. Clematis alpina: Perfect for growing against a garden wall, over an arch, pergola or trellis, or for training through the supportive branches of a sturdy shrub or small tree, this ultra-hardy, easy-to-grow, long-lived, deciduous, spring flowering climber is prized for its understated elegance and generous display of dainty, bell-shaped blooms. Happy in full sun or light shade, it likes a rich, cool, moisture-retentive but free-draining soil and will typically reach a height and spread of 2m by 3m. The lavender-blue flowering variety known as 'Frances Rivis' is probably the best known but other garden-worthy varieties include the pale-pink flowering 'Willy', rose-pink 'Constance' and the beautiful white-flowering 'White Moth'.
2. If you secretly find the egg-yolk yellow flowers of conventional varieties of daffodil (Narcissus) just a little hard on the eyes, then the fragrant, ghostly-white, flowers of late-blooming kinds such as 'Cheerfulness', 'Winston Churchill' and the delicate 'Double Poet's' (Narcissus poeticus 'Plenus') will be much more to your taste. Not only do they smell heavenly but the flowers of these easy-to-grow, long-lived bulbous plants are also perfect as cut-flowers. Like almost all narcissus, they like a cool, rich, moisture-retentive but free-draining soil. Just watch out for slugs, which sometimes like to eat the flowers when still in bud.
3. Lungwort or pulmonaria is another stalwart of the April garden with supremely pollinator-friendly flowers in shades of blue, lilac, pink, red, and white as well as handsome foliage often mottled in silver. This relatively compact, ultra-hardy long-lived perennial is perfect for a shady corner where it will provide valuable groundcover. Some varieties, such as the ghostly Pulmonaria 'Sissinghurst White' remain semi-evergreen while the classic violet-blue 'Blue Ensign' is happy to grow in full sun as long as you give it a cool, humus-rich moisture-retentive soil.
4. Honesty, or Lunaria to give it its Latin name, is best-known for its highly ornamental, silvery seed-heads which are very popular with floral designers. But it's also an excellent plant for the spring garden with tall stems covered in dense clusters of small, pollinator-friendly flowers in shades of lilac, purple and white. Although honesty is a relatively short-lived, hardy biennial typically sown in late spring/early summer to flower the following spring, it's a very generous self-seeder that will happily sprinkle itself around the garden if given its preferred growing conditions, which are full sun/light shade and a fertile, moist but well-drained soil. Along with the purple-flowered species and the very lovely, white flowered 'Alba', look out for the varieties known as 'Chedglow' (lilac flowers and chocolate-tinted foliage, seed available from avonbulbs.co.uk) and 'Corfu Blue' (violet-blue flowers and violet-tinted foliage, seed available from chilternseeds.co.uk). All associate very well with spring-flowering bulbs.
5. Like a forget-me-not on steroids, the hardy herbaceous perennial known as Siberian bugloss (Brunnera macrophylla) produces its delicate sprays of sky-blue or white flowers above dense clumps of heart-shaped leaves, reaching an average height and spread of 50-60cm. In the variety known as Brunnera 'Jack Frost', those leaves are generously mottled in silver, resulting in a beautiful groundcover plant that gives months of interest. Best in a cool, moisture-retentive, humus-rich, fertile soil in dappled shade, it will tolerate dry shade once established.
6. With their fondness for ericaceous (acidic) soil, plentiful rainfall and lots of growing space, rhododendrons will not suit every outdoor space, but these majestic shrubs are one of the many joys of the April garden. To see them at their best, visit the National Botanic Gardens at Kilmacurragh in east Wicklow, which is home to a remarkable historical collection of rhododendrons that thrive in its mild, moist climate and acidic deep brown earth including Rhododendron arboreum sub-species cinnamomeum, which was grown from material collected in the wild by Sir Joseph Hooker in India. Ultra-compact varieties suitable for container-growing include some of the 'yak' hybrids such as the peachy-pink flowering R. 'Percy Wise'.
7. Tulips: That this vast and beautiful genus of plants once seduced and bankrupted the Netherlands, during the "tulip mania" in the 1630s, probably best sums up its extraordinary charms. It's far too late to plant their fleshy bulbs for a colourful display this spring but you can still buy potted plants in garden centres for popping into pots and containers to add spots of seasonal colour. To see tulips used in brilliantly creative combinations and in ultra-generous quantities (I'm talking tens of thousands), pay a visit to the Wicklow garden of June Blake, which is celebrating their extravagant beauty throughout April, plus a free guided tour of the gardens by its owner every Sunday (2pm). Tulips do best planted deeply (25-30cm) in late autumn/early winter in a free-draining, not overly fertile soil in full sun. For tulips in April, go for the taller, later-flowering kinds such as Café Noir, 'Havran', 'Negrita' 'Burgundy', 'Merlot', Jan Reus' and 'Ballerina'.
8. Magnolias are one of the shrubby glories of the spring garden with showy blooms in shades of pink, white and pale yellow. Among the best is the relatively compact, hardy, deciduous variety known as 'Susan', with goblet-shaped, pink flowers on bare stems from April-June. Reaching an average height and spread of 3-4m, it likes full sun or light shade and a moisture retentive but free-draining acidic soil. Also flowering on bare branches in April and a good choice for the smaller garden, the fast-growing Magnolia x loebneri 'Leonard Messel' reaches an average height and spread of 5m, has star-shaped pale pink flowers and will tolerate alkaline soils. For smaller gardens, a great choice is the new cultivar known as Magnolia 'Fairy Blush' which produces its scented, pale pink flowers in profusion from March to May and then intermittently until early autumn. Reaching an average height and spread of just 2.5-3m, it's semi-evergreen with a bushy, compact growth habit.
9. I've written recently about the glorious sight that is a spring flowering cherry tree in full bloom. Varieties that bloom in April include the Japanese flowering cherry known as Prunus serrulata 'Kanzan', an enduringly popular, showy variety with dense clusters of candy floss-pink flowers, the lovely Shogetsu cherry (Prunus 'Shogetsu') whose large, pale double flowers typically appear on elegantly dangling stalks in April and Prunus serrula 'Tai-haku', a medium-sized tree with handsomely rust-coloured bark and large, single white flowers, which reaches an average height and spread of 10m.
10. With their dainty, checkered flowers in shades of plum and cream, the graceful, hardy, spring flowering bulbous plant known as Fritillaria meleagris or snake's head fritillary is perfect for a woodland garden or for naturalising in generous swathes in damp, fertile meadowlands or along grassy banks. Like most spring-flowering bulbs, it should be planted in autumn but you'll often find potted plants in flower for sale in good garden centres at this time of year. Bring them home, plant them out and with luck they'll self-seed over time. Just watch out for the lily beetle, an invasive pest which has become more common in Irish gardens over recent years and which likes to feed on the foliage and petals of fritillaries. If you spot the orange eggs (you'll find these on the underneath of the leaves), the larvae or the adult scarlet beetle itself, squash them quickly between finger and thumb to prevent them from causing damage.
This Week in the Garden
As long as soil conditions aren’t too cold or too wet, mid-April is a good time to direct sow early varieties of peas, turnips, radishes, beetroot and parsnips outdoors into well-prepared, weed-free soil that’s been raked to a fine tilth. To give direct-sown seed an extra burst of heat to aid germination, it’s well worth covering the soil with a layer or two of garden fleece both before and after sowing. Just make sure to peg or weigh the edges of the fleece down to prevent it from being disturbed by strong winds.
If you're looking for a floriferous, pollinator friendly, long-flowering annual to give some serious colour punch to your garden this summer, then the half-hardy, easy-to-grow annual known as cosmos is an excellent choice. April is an excellent time to sow the seed under cover and in gentle heat, while making sure to protect the emerging seedlings from cold night-time temperatures. Many different varieties are available to buy as seed including the tall, pale-flowering 'C. 'Psyche White', crimson-and-white 'Velouette' and the pale-yellow 'Xanthos'. Recommended seed suppliers include all good Irish garden centres, mrmiddleton.com and seedaholic.com
If you’re growing seedlings or young plants under cover in a glasshouse, polytunnel or cold frame, unless you keep a very careful eye on ventilation at this time of year, temperatures can very rapidly rise inside them on bright, sunny mornings to the point of stressing young seedlings/plants or even killing them. So make a point of opening vents, doors and windows on bright, sunny mornings. Equally, temperatures can quickly plunge in polytunnels, glasshouses and cold frames at this time of year as nightfall approaches, so it’s just as important to close them up in the evening to protect vulnerable plants from damage.
Dates For Your Diary:
Sunday, April 14th, June Blake's Garden, Tinode, Blessington, Co Wicklow, all-day charity event in aid of Christina Noble Foundation, with free guided tour of the gardens by owner June Blake at 2pm, tea rooms and bookshop open, see juneblake.ie; Wednesday, April 17th (8pm), Parish Centre, Church Road, Malahide, 'Growing & Showing Dahlias for Chelsea', a talk by floral artists and dahlia expert Christopher White on behalf of Malahide Horticultural Society, with dahlias and cuttings for sale, see malahidehorticulturalsociety.com or contact John Warren on 087 2561761; April 18th-June 3rd, Kiltrea Bridge Pottery, Kiltrea Bridge, Enniscorthy, Co Wexford, whose beautiful terracotta pots grace many Irish gardens, will be holding a farewell sale as this much-loved family business closes its doors to the public following the retirement of its owner and chief potter Michael Roche and his wife Johanna, see kiltreapottery.com; Sunday, April 21st and Monday, April 22nd (10am-5pm), Farmleigh, Phoenix Park, Dublin, ISNA Plant Fair with a wide range of choice, Irish-grown plants and garden accessories for sale, see irishspecialistnurseriesassociation.com