Under the icy surface of a frozen garden pond, plants and creatures adapt to survive winter's chill...
It is deepest winter, and the garden pond is buried beneath bleached ground. Sparse stems of robust plants jut through the pure white cover, as though reaching for warmer heights, their remaining leaves brittle and laced with frost. Settled snow hides the pool’s periphery, smoothing the edges as shoreline and surface are blended into uniformity.
The pond dozes through a seasonally imposed, cryogenic sleep. Aside the tracks of passing cats and birds pressed into the crisp covering, there is empty desolation. Yet still, life remains; it has just sunken. Below the surface, biological clocks tick and skeleton workforces continue to labour.
The upper levels are abandoned. As ponds cool, the life they contain relocates progressively deeper, an exodus from the surface ice to follow. Governing this are changes to the physical properties of water, brought about by the low temperatures. For aquatic life, these changes are essential for survival, as without them, the pond would freeze solid.
The main parameter altering the pond’s very dynamic is water density. Liquid water is most dense at 4°C. At temperatures below that, it thins again, until it solidifies as ice. This results in thermal stratification, where dense water sinks, and cooler water forms layers on top. This is partly why ice starts at the surface, instead of throughout.
For aquatic residents, the denser, warmer layer represents a safe oasis at the very limit of their temperature tolerance. This safety can be easily compromised. Depth is critical: if the pond is too shallow, then stratification will not occur. Small bodies of water, less than 35in (90cm) deep, can be hostile to even hardy life. Fish may need to be rehoused indoors while the worst of the season passes.
Fountains or circulation pumps can impact temperatures, mixing the various densities of water together and cooling them until ice starts to form at all depths. At a microscopic level, the pond becomes a semi-solid slurry, causing tiny frozen crystals to form within the tissues of plants and animals. The resulting physical damage can be lethal for anything using the pond as a home, as plant cells rupture, insect shells split, and gills and organs of fish are lacerated.
There are roughly three million manmade garden ponds in the UK. Many are a forced coexistence of native and imported flora and fauna. Among them, goldfish originating from East Asia rank as the country’s favourite alien inhabitants and for good reason. Their tolerance to temperature extremes helps them endure the wide fluctuations of a comparatively balmy British climate.
Wildlife that can avoid fish predation exploit garden pools in winter. Frogs and newts bury themselves in silt and slurry, part camouflage, part insulation, becoming dormant at 5°C. They remain so until the warmth returns, drawing oxygen from the water directly across their skin, known as cutaneous respiration, rather than inhaling atmospheric air.
Insects are found beneath the ice. Truly aquatic species, such as water boatmen and great diving beetles, are ill- adapted to living outside a body of water. They periodically roam the underside of the frozen sheet, seeking out bubbles of air. The young of some aquatic beetles overwinter in muddy ponds, living as larvae buried at the base. Others, in adult form, crawl out for drier refuge.
Crustaceans do not take a winter break. Many amphipods and isopods, such as woodlice, spend their whole lives among the substrate. They are leaf shredders, gnawing through food that has fallen into the pond, and mulching it into a fine detritus. The falling leaf bounty of autumn is sufficient to see them through long-drawn winters.
Microbes in the pond may still function at low temperatures. Some are even found after centuries of dormancy in harsh Arctic permafrost. Though activity levels are seriously compromised, they still use any available carbon, nitrogen and oxygen locked away in the pond’s waste, as well as oxygen in the water, to convert organic debris into a mixture of energy and effluvium.
The hermetically sealed box of a frozen pond presents a problem here. Bacteria feeding on debris produce carbon dioxide, methane, hydrogen sulphide and a farrago of other noxious gases. With nowhere to escape, these gases accumulate, poisoning higher life. To avoid this, excess sediment must be removed with nets or aquatic vacuum cleaners before the winter sets in.
With the sun gone, plants divert energy from stem or leaf growth, focusing attention on their roots. By storing carbohydrates in their bulbs, roots or rhizomes, they have adequate reserves to subsist frugally until light returns and photosynthesis can resume. Water lilies stop any surface growth. New leaves will sprout in spring, and they are best left alone until then. Provided they have had a productive summer, they will return more strongly, year on year.
Many introduced plants, especially floating ones, stand little chance. Removing them to an indoor bucket may be their best hope for survival. Indigenous plants and those from northern climates, such as the spiky water soldier, will follow everything else to the bottom. Here, they adopt a submarine lifestyle until conditions improve. Where foliage has evolved this means of survival, it will adopt it without prompting.
Deeper oxygenating plants and algae stay minimally active. As long as some light can reach them, and carbon dioxide is available, they continue a lethargic photosynthesis, trickling out oxygen. Darkness forces them to respire, with plants dipping into their energy stores of sugar when the nuclear force of light is unavailable. This in turn causes them to produce carbon dioxide instead. In a smaller pond, this is avoided with the regular clearance of snow from its surface. Larger ponds will be too hazardous to stretch across.
Goldfish care in winter is easy: they are left alone without food. As cold-blooded creatures, unable to generate their own body heat, their metabolic rates are enslaved to water temperature. Feed rates need to be drastically reduced below 10°C, while sub-8°C digestion is entirely dormant. Feeding during a reprieve between cold snaps risks filling their bellies with indigestible fare when the temperature dips again. When snow and ice prevail, feeding is suspended.
Breaking surface ice to create breathing holes is often counterproductive. The pressure waves from any sudden impact are enough to shock fish, often to a lethal degree. Just as bad is the use of boiling water, which will cause acute damage to any life it meets as it mixes.
Floating pond heaters will help to the extent of clearing some surface ice, but do little beyond that. In the cold, oxygen travels approximately 2mm a day through static water. Given that pond life migrates to the bottom, it takes weeks or months for the gas to travel down that far. Breathing holes in ponds are superfluous, except where gases inside the pond need to be released. Unless excessive gas bubbles form on the underside of the ice sheet, or the pond is catastrophically overstocked, then holes are not essential.
Until spring’s thaw, it is wise to let the inhabitants of the pond continue to do what they have been successfully doing unaided for millions of years.
Words Nathan Hill
Myriad early flowers and blossom fill a riverside garden in Kent, its planting a legacy of one woman’s vision.
On the outskirts of the ancient Kentish village of Yalding, a narrow lane leads across the floodplain of the River Medway to the daffodil-flanked drive of a former oast house. This is Parsonage Oasts, the home of Edward and Jennifer Raikes. In spring, the garden erupts into a haze of flowering trees and shrubs. White magnolia and Ribes sanguineum compete and blend with red and pink Japanese quince and camellias. All are under-planted with more than 30 types of daffodil, fritillaria, hellebores, lime green euphorbia and tiny tulips.
The early 19th century red brick and timber-clad oast house, originally designed to dry hops, occupies an idyllic position at the water’s edge. There are sweeping views in both directions of the Medway. “The river is a great asset. I like seeing the people and the birds on it,” says Jennifer. “It keeps the garden a bit warmer. But it also means that the soil is very light and full of gravel. It dries out a lot, so needs plenty of watering to encourage plants such as grape hyacinths and geraniums to get going.”
To this end, seven water butts are dotted around the ¾ acre plot to collect water from various roofs. Jennifer also relies on plentiful supplies of spring water pumped up from a small well. This is situated behind the house on a patch of lawn. Sometimes the river contributes too. Yalding hit the national news over Christmas 2013 when it was flooded after a deluge of rain. Parsonage Oasts did not escape and the garden was doused. The floodwater disappeared as quickly as it came and left no lasting damage to the plants, trees and shrubs. The main victims were the beehives Edward has kept for 30 years, although these have been replaced now.
The Raikeses are used to the river’s moods, having lived at Parsonage Oasts since 1968. They moved in to help look after Edward’s grandmother, Gladys, in her very old age. “It was Gladys who made the garden when she came here in 1954,” says Jennifer. “She bought the derelict oast and a parcel of land from Parsonage Farm and, with the help of her architect, turned it into a home. Aided by a local man with the lovely name of Mr Startup, she started to create the garden out of the farmyard, which was a complete bramble patch, all overgrown.”
Although Gladys was well into her 70s, she planted magnolias and apple trees. She also put in hedges of yew, box and shrubby honeysuckle. Lawns were laid out and low brick walls built, with gravel pathways that flowed around the garden. She put in a small rose garden and a variety of shrubs. “It was already a very nice garden when we came here,” remembers Jennifer. “But, as we spent most of our time looking after our three small children, it got quite overgrown and weedy. It was only after they got a bit bigger that we began to garden in a more serious way, at the end of the ’70s.”
An outside dining room
One of their first major additions was an arbour on the sun terrace outside the drawing room. This was created for a young strawberry vine, Vitis vinifera ‘Rembrandt’, to clamber over. “The vine is a cutting taken from an original planted by Gladys. That had died in 1971, the same year as Gladys died. We got some old water pipes from a junkyard and put them up.”
In spring, this wonderful old vine starts sending out new shoots, which result in masses of edible, bronze-coloured grapes in late summer. With its snug position against the house, the sun terrace is one of the Raikes’ favourite places to sit. As soon as the weather is good enough, they take their meals out here, breakfast, lunch and dinner. Tucked into one corner is a favourite garden ornament, an armillary sphere. A pidgin Latin inscription translates as: “This garden is the fruit of the wisdom of Gladys Raikes.” It was made for them in 1975 to commemorate Granny’s creation of the garden.
To the left of the terrace is a low brick wall, beyond which is the river. Beneath it, a well-stocked herbaceous border is brightly lit with bold, orange-flowered crown imperials, Fritillaria imperialis. Its large bulbs are planted between the burgeoning lilies, geraniums and tulips. “Granny put some in to start with, but I do keep them topped up, and they carry on year to year,” says Jennifer. “They are scene-stealers, very dramatic.” There is a great deal of foliage as well, because Jennifer loves the soothing qualities of the colour green. “I like white, silver and green together, and contrasting leaf shapes,” she says. “These range from pointy such as fritillaria, and palmate, geraniums for example, to big sheaves of leaves such as tulips and daffodils.”
From the terrace, there is a picture-postcard view onto one of Granny’s best legacies. On the far side of the well-kept lawn, a huge Magnolia x soulangeana, or saucer magnolia, is covered in lightly scented flowers. “The magnolia comes in March,” says Jennifer. “It is at its best at the beginning of April, then has a second flowering in July. We mulch it every autumn with its own leaves and a bit of fertiliser, perhaps some hoof and horn.”
Next to the magnolia, and helping to set it off, is the tiny, snowy blossom of a delicate white flowering currant, Ribes sanguineum. Jennifer planted this to increase the visual interest in that corner of the garden. Beneath both trees are swathes of purple hellebores Helleborus purpurascens, white windflowers Anemone nemorosa, and drifts of daffodils. This underplanting seems to anchor the nut-brown trunks in a sea of gentle colour that enhances all the varieties of green Jennifer adores.
Another of Granny’s stars lies across the lawn to the right of the arbour. This is a large and prolifically fruiting ‘Gascoyne’s Scarlet’ apple tree. “It has the most gorgeous blossom,” says Jennifer. “Despite its age, last year we had 130 bottles of juice from it. Edward prunes it very severely in February or early March to keep that parasol shape. It’s quite a big job and takes a couple of days to do properly.” Approximately three decades ago, Edward attached a swing to one of the tree’s sturdy branches for their grandsons to use. It is still being enjoyed now by their youngest granddaughter, Etta.
Spheres of box
One of Granny’s introductions that did not stay the course was her rose garden. This originally led out from a back door, bisecting the lawn, in front of the apple tree. “By the late 1970s the beds were full of bindweed and the roses weren’t doing well. We took the whole thing out to replace it with something less high maintenance,” says Jennifer. In its place, they put down a simple gravel path, flanked by two rows of hardwearing Tunbridge Wells paviours, interspersed with box balls to create a focal point. “Each ball is made up of up to 30 plants that have grown together to form a mound. Edward always trims them on Derby Day [the first Saturday in June],” says Jennifer. The magnificent spheres are now 3ft (1m) in girth. They are teamed with pots of abelia ‘Sunshine Daydream’ and ‘Confetti’, chosen for their contrasting pale pink-green-yellow foliage.
At the end of the lawn, through a gate and down a few steps, is the wild garden. This is dotted with all manner of trees, including ash, oak, pine, willow, crab apple, alder and hornbeam. In 1999, they dug a pond on the side of the wild garden nearest the river to encourage frogs, though none have yet colonised it. “We bought a pocket of woodland in 1996 with the idea of having a managed wildness. This area is full of old-fashioned daffodils, bluebells, snowdrops, white Anemone blanda and hybrid whitebells. Someone gave me a sack of them, so I planted them all here.”
A hawthorn that was taking light from the area has been cut down. Instead, they have started to plant camellias, which like the shady, slightly damp conditions. On the little path above that looks into the wild area from the main garden, camellias in pots are putting their roots down to get established. So far, the collection has approximately 15 varieties.
Returning to the formal garden, beyond the apple tree, the flower beds running next to the house are punctuated with a variety of scented shrubs. There are wintersweet Chimonanthus praecox, and winter honeysuckle Lonicera fragrantissima. “You can’t beat natural fragrances,” says Jennifer. She is delighted to add another sensory element to her spring garden with shrubs such as sweet box Sarcococca confusa, and the deliciously scented daphne ‘Eternal Fragrance’.
A host of daffodils
On the far right of the garden is a storage area in the shape of ‘the little barn’. Growing next to this former bullock shed is a striking Japanese quince, Chaenomeles speciosa, creating spring impact with its intense red flowers. In front of the bothy, the kitchen garden is now starting to burst into life.
From here, the path meanders through a gate round to the front of the house, past drifts of more daffodils. “We started putting in the daffodil bulbs about 20 years ago and now have over 30 varieties,” says Jennifer. They start flowering in December with ‘Rijnveld Early Sensation’ and finish in May with ‘Pheasant’s Eye’. Some of her favourites include the heritage variety ‘Baths Flame’, bred pre-1913, and the modern white daffodil ‘Thalia’. Other favourites include scented narcissi such as bright yellow ‘Little Witch’ and white and yellow ‘Jack Snipe’. “We don’t replenish the daffies because they last forever. We do get a few extra varieties every year from our local bulb specialist, de Jager,” she adds.
The Raikeses work in the garden all year round, planting, weeding, pruning, clipping, mowing, edging and mulching. Tasks include growing on cuttings from favourite plants such as Jennifer’s collection of pelargoniums.
The spring season, however, is a time of enormous pleasure and anticipation of good things to come. “The garden delights both of us,” says Jennifer. “It’s our hobby like other people play golf or have a yacht, and we’re out in it most days. But we don’t spend huge amounts of money on it. We have lots of plants given by friends, and I give away cuttings and bulbs too.”
Her favourite time in this season is between 4pm and 5pm. This is when she potters round to see what needs a bit of attention, such as feeding or tying in or deadheading. “Plants need help, of course they do, and the garden is very much a work in progress,” she says.
Words: Caroline Wheater Photography: Abigail Rex
Parsonage Oasts, Hampstead Lane, Yalding, Kent, ME18 6HG. Tel 01622 814272.
With subtle tones and smooth curves, an Essex garden quietly bursts into life.
Down a country lane, past wooded glades and heathland, sits a garden brimming with unfurling foliage and pristine spring flowers. In the crystal clear sunlight of early morning, a myriad of tulips shimmer from beds and borders. All are carefully colour-themed and blended with ornamental grasses, burgeoning perennials and evergreen shrubs.
Furzelea, a Victorian house, lies outside the village of Danbury, Essex, on a south-facing hillside. As one of the highest points in the county, the incline is regularly brushed by cold easterly winds. The surrounding woodland, however, forms a natural shelter-belt that allows tender plants to survive winter. The soil is a mix of sand and clay that, combined with the typically low rainfall of this area, creates dry conditions. As a result, regular mulches of compost are needed to increase water retention, while watering in prolonged warm spells is vital for the plants to thrive.
Welcoming the tulips
Owners Avril and Roger Cole-Jones have gardened on this plot for 36 years. They greet each spring with keen anticipation.
“I love to see the garden coming to life again after winter, with
new shoots breaking through the earth, fresh leaves emerging
on the trees, and a succession of bulbs,” says Avril. “I am no lover of yellow, and big golden daffodils are my pet hate. So
after the snowdrops and dainty white narcissi, tulips are what
I look forward to.”
When the couple first arrived in 1980, the one-and-a-half-acre garden showed little promise. “It was a jungle of self-seeded birch, oak and blackthorn. We could not even see the boundaries,” recalls Avril. Roger hacked a tunnel through the undergrowth, their two young daughters closely bringing up the rear, until he reached the thatched summer house at the end of the plot. He set himself a target of removing seven tree roots a weekend – an antidote to his job as an electrical engineer. Over several years the garden was cleared. “He unearthed much of the Victorian brick edging. We incorporated it into the new garden, laid on end at 45-degree angles to edge beds, paths and borders,” says Avril.
In the early years, one half of the garden was used as a paddock for the children’s ponies, while the remainder was laid largely to lawn. “We built several arches and pergolas from timber that came from the felled trees,” says Avril. The ponies left in 1991 and strips of the original garden were sold for development a few years later. She could finally realise her dream of developing the remaining two-thirds-of-an-acre plot. “The time had come to divide the garden into separate rooms,” she says. “I wanted to do this, not by creating dense screens from formal hedges, but with informal plantings of shrubs and small trees. That means there’s still a hint of what’s round the corner.”
Dividing the garden
Initially, Roger was horrified at the thought of no longer being able to see all the way from the sitting room window to the back hedge, but Avril prevailed. “I wanted a garden that you couldn’t see all in a glance, with hidden areas that would entice us outside, however bad the weather.”
Together, they started planting trees and shrubs to create partial, informal divisions between different areas. The lawn was stripped back to form beds. “Before we start a new project,
I always sketch out my ideas to scale, and then translate them onto the ground to check that they will work,” she explains. “I can’t draw so they’re little more than doodles on paper, but
I do have an eye for colour.” From the start of work in 1997, the garden is an ongoing project, continually developing.
The layout is based on circles and curves. This creates a continuous flow from one area to another, as opposed to a staccato series of beginnings and ends. “There’s something very pleasing about curves,” she says. The main view is from a raised stone terrace that lies immediately outside the kitchen. This directs the eye down the sloping garden. There are tantalising glimpses of a pond, arches, a thatched roof and shapely trees.
From the terrace, eight brick steps descend to a lawn, each side bordered by stepped box hedges. “I wanted some sort of barrier alongside the steps, but nothing as permanent as brickwork. Box hedging was ideal,” explains Avril. More box hedging edges an island bed to the right, encircling a willow standard. Just a few steps away is a large circular bed, edged in some of the original Victorian bricks. This is planted with a soft blend of buttermilk violas, wallflowers, narcissus ‘Cheerfulness’ and yellow tulip ‘Fringed Elegance’. “I prefer the pale primrose yellow of this tulip to deeper golden shades,” she says.
Past the pond
A grassy path leads from the circular bed down the garden, straddled by a wooden pergola bearing the double blue Clematis macropetala ‘Maidwell Hall’. To the right lies a pond, once
home to the family’s ducks. This was enlarged five years ago, excavated to a depth of 24in (60cm), and relined. “The ducks had pecked away the original grassy edges, so we built straight-sided walls topped with bricks. This helps deter the heron from eating the goldfish.”
The grassy path continues southwards, passing camellias, a purple-leaved cherry and flowering Magnolia soulangeana. It arrives at a rustic arch covered in Akebia quinata, the chocolate vine. This produces clusters of wine red, chocolate-scented flowers in spring. “Wherever a path provides a natural passage to another part of the garden, it lends itself to an arch for climbing plants,” says Avril. “I like the idea of structures in the garden not only being features, but also having a purpose and being used.”
This arch is used to frame the view of the lowest third of the garden. Here a circular lawn is overlooked by a thatched summer house, flanked to each side by twin topiary shapes. “They started out as boring potted balls, so I gradually clipped two cottage loaf-style layers. Since then, we’ve kept adding layers.” The curving lawn is enclosed by borders filled with late-flowering tulips, primarily chosen for their colours and differing heights. “I leave tulips in from one year to the next. The deeper they are planted, the greater the chance they will return, largely because there’s less chance I will inadvertently put a fork through them,” she adds. Avril only digs deeply when planting anew. Otherwise she does little more than use a small hand fork to weed, or break the crust of the earth allowing rain to penetrate.
The palette of tulip colours changes subtly, creating an informal effect. Pinks and mauves flow down the eastern border, beneath a pink blossoming prunus ‘Kiku Shidare Zakura’. They pass a clump of blue Muscari armeniacum that originated from Roger’s mother’s garden. In the bottom border, there is an old camellia, Magnolia liliiflora ‘Nigra’ and a shrimp-pink Acer pseudoplatanus ‘Brilliantissimum’. Here, yellow and orange tulips start to dominate, changing to reds, oranges and creams along the western border. “There are no sharp contrasts, just
a gradual change of colour,” says Avril. Among the many tulips she grows, a particular favourite is the scented orange tulip ‘Ballerina’. This returns annually, each year a little shorter than the one before. She covets it for its lily shape, beautiful clear colour and fresh, strong but sweet fragrance. “I always add new bulbs to the existing clumps, so that there are different heights. It looks much more natural.”
No fan of the municipal-style massed planting, her preference is to mix tulips in with other plants. “I hate the idea of serried ranks of tulips standing over forget-me-nots or pansies,” she says. Instead, she favours specific pairings, such as red ‘Abu Hassan’ tulips with variegated sisyrinchium, and burnt orange ‘Cairo’ with Euphorbia polychroma. Other combinations include pink ‘Caravelle’ with honesty, and ‘Ballerina’ with either rusty-coloured Carex testacea or Carex elata ‘Bowles’ Golden’. “Carex are reasonably evergreen and there are eight varieties that look good in spring,” says Avril. “Grasses go well with tulips, creating a lovely informal look.”
Letting the sky in
Among the other ornamental grasses she grows are Anemanthele lessoniana, Calamagrostis x acutiflora ‘Karl Foerster’ and Deschampsia flexuosa. These are interspersed among tulips in various shades of pink that drift through the large island bed in the centre of the circular lawn. Shaped in the manner of a three-leaf clover, this bed was formed just two years ago after being marked out and stripped of turf. “We hired a rotovator to excavate down, and added our own compost. With undernourished soil like ours, you can never have enough.” Now well established, it is a very different picture from the huge old red-flowered chestnut that stood there until 2008 when it was felled by a mini tornado.
That occurred two weeks prior to a charity opening of the garden. The rotten stump was quickly dug out, then the hole backfilled with topsoil and turfed over. “We finished the day before the first visitors arrived,” recalls Avril. She now prefers to see the sky and cloud formations rather than a dense tree canopy. “Big trees hide the sky, and the grass beneath struggles to grow,” she points out. “Even when a tree is used to block an unsightly view, it often grows too tall, and hides something you’d otherwise choose to see.”
As a result, she prefers shrubs and bamboos with a finite height, or small trees that will not rob the garden of light. For example, in the island bed stands a Cercidiphyllum japonicum, the katsura tree. This is a deciduous tree with beautiful heart-shaped leaves that open a soft bronze before turning green and colouring up in autumn. Beneath it are tulips in various shades of peach and coral. Threaded through them are silver clumps of leafy Artemisia ludoviciana ‘Valerie Finnis’ and Astelia chathamica. A variety of heucheras, including ‘Mocha’, ‘Brass Lantern’ and ‘Marmalade’ with leaves in shades of bronze, coral and caramel sit with bronze fennel.
An outcrop of Euphorbia mellifera adds height, while there are
a number of spiky phormiums. Among them are pink-striped ‘Maori Queen’, gracefully arching ‘Jester’, and compact, brightly coloured ‘Flamingo’. “The old-fashioned Phormium tenax grow too big, but most modern varieties are smaller. They come in
a range of eye-catching colours and, being more arching in habit than upright, blend easily into the planting.” By mid spring, Avril’s phormiums are immaculate thanks to tough treatment earlier in the season. “I hack back any damaged leaves and they look so much better after being thinned out.”
Different phormium varieties punctuate the borders enclosing the circular lawn. They culminate at the top of the western border with a magnificent Phormium tenax ‘Purpureum’. This provides a dramatic, dusky backdrop to orange ‘Ballerina’ and caramel-coloured ‘Cairo’ tulips. To the right is a second archway that frames a view of the White Garden, sitting in a quiet corner bordered by the boundary fence, house and, to the east, the pond. A white metal bench is surrounded by a border of tulips ‘White Triumphator’ and ‘Queen of Night’, narcissi, spirea, alyssum and self-seeding honesty. “It’s a lovely quiet place to sit with a cup of tea, when I find the time,” adds Avril.
Time is in short supply because maintaining a garden ofmsuch interest is almost a full-time job from spring until autumn. But Avril would have it no other way. “I’ve always gardened, helping my mother sow seeds from a very young age. I can’t imagine life without a garden. It is forever stimulating and, with the unpredictability of the climate, is never dull, even if the outcome is not always what you expect.”
Furzelea, Bicknacre Road, Danbury, Essex CM3 4JR.
Tel 01245 225726.
Words and photography: Nicola Stocken
PLANTS KEEP CHANGING THROUGHOUT THE ICY MONTHS TO PERFORM WELL IN THE SPRING AND SUMMER
Under its seasonal covering of snow or frost, the winter garden appears dead and lifeless. Brave splashes of colour come from witch hazels, viburnums and a few other shrubs. But the majority of the garden seems to be sleeping, waiting for the warmer weather and longer daylight hours.
This is an illusion. The garden never sleeps, and all winter there are subtle but vital changes taking place. Under the soil, the cold is working its magic on seeds, bulbs and roots. Even the chill winds have a role to play to ensure flowers and fruits appear later in the year. Without the winter cold, gardens would be less beautiful in the summer.
A period of cold weather is essential to many plants and crops. Without it, some would struggle to grow at all, while others would not flower or produce crops.
One example of crops that need a cold spell are fruit trees such as apples, plums and pears. If temperatures remain high, these trees would not come into growth in spring, nor produce flower buds. In a process known as vernalisation, the reduction in daylight initially induces the trees to go dormant. They shed their leaves, which would require too much energy to maintain in winter when they make less food. Then the trees must be exposed to a certain number of days with a minimum temperature, usually less than 7°C. Only when this has happened are they ready to burst into growth and bloom when temperatures rise. This process is designed to ensure this happens in spring, and not in autumn.
The amount of days of cold required is expressed in chill hours. Some require longer periods of cold than others, although the reason for this is not currently known. However, the plants are believed to store the necessary information and pass it on in their genes.
Bulbs in winter
Hardy bulbs need different weather conditions at different times of the year to grow and produce flowers. Flower bulbs are formed in summer, as a result of heat in a process called baking. Root growth is stimulated by the cooler and wetter weather of autumn. However, it is the cold of winter that is needed to stimulate stem growth. Temperatures of 10°C or below trigger the elongation of the flower stem.
Attempts to grow hyacinths or daffodils in the home often results in hyacinths with a clump of flowers crowded in the neck of the bulb or daffodils on dwarf stalks. This is the result of ignoring the bulbs’ need to spend at least 10 weeks in cool conditions, ideally outside below 10°C. There are exceptions to this such as ‘Paperwhite’ and ‘Soleil d’Or’. Native to warm Mediterranean regions, they do not need a period of cold for their stems to grow. It is autumn rain, rather than winter cold, that spurs on these daffodils’ growth.
Getting ahead in the race for light
In winter, herbaceous plants stop growing and die back. Instead, they store the carbohydrates they make from water and carbon dioxide from the air in their roots. This provides the plants with a reserve of energy, designed to give them a head start in spring. They store the carbohydrates as starch because this is more concentrated in energy (calories) than simple sugars. Starch is not water soluble, making it difficult to move around the plant in the sap.
The onset of cold weather, however, triggers enzymes in the root to convert the starch back into soluble sugar. This means it can be moved to the growing tips of the plant, ready for early spring’s surge of growth. Once the conditions are right, they are able to push their shoots to the sunlight ahead of surrounding plants such as annuals. This stops the new growth from being smothered by the hundreds of annual seedlings which are germinating at the same time. Peonies and dahlias are both examples of the wide range of plants this benefits. It is also the reason why parsnips taste sweeter after they have been frosted.
Saving the next generation
When grown from seed some plants need a cold spell before they will flower. These include biennials such as wallflowers, aquilegias, sweet Williams and onions. Blooming in late spring, they release their seeds in summer. If the seeds germinated immediately, they would flower and set seed as soon as they were big enough. These new seeds would not have time to ripen before winter arrived. The cold weather would kill them, with the loss of a whole generation. Instead the plants make healthy clumps of foliage the first year. Then they wait for a sufficient winter chilling before producing flowers. No matter how early in spring these seeds are sown, they will only produce leaves in the first year, never flowers.
The necessary cold period to stimulate flowering can be very short. Several biennial plants, such as parsnips, carrots, beet and onions, are grown as vegetables. The starches and sugars stored in their roots provide valuable food when eaten. If these vegetables are sown too early in spring, there is a risk of short cold snap while they are growing in April or May. This could fool them into thinking that winter had come and gone, and it was time to flower. At this point the plants ‘bolt’, sending up flower stems and the crop is lost to the gardener.
The biennials above require winter chilling to make them flower. There are other plants, however, that need their seeds to be vernalised before they germinate at all. The seeds undergo a period of dormancy. In some cases, simply the softening of the hard coat by frost and weathering action will allow the seed to germinate. This applies to some lathyrus species including sweet peas.
In other cases, this weathering is linked to the need for a cold, moist period. This triggers the seed’s embryo to grow and expand. It breaks through the softened seed coat seeking the sun and nutrients. Seeds do this because if they germinated in autumn, the seedlings would be unlikely to survive the winter. If frost did not kill them, grazing animals, slugs and snails would eat them in the absence of other food. Delaying germination till spring gives every seed a better chance of survival to maturity.
All these processes show that winter is not just a time of frosty beauty. Its chilling weather creates more than a snowy landscape, it plays an essential role in ensuring that the following season is as productive and beautiful as the last.
Words: Geoff Stebbings Photography: Alamy
VIVID BERRIES AND LEAVES OF SPINDLE TREE PROVIDE FOOD FOR BIRDS AND VISUAL TREAT
With the approach of winter, spindle trees start to set the garden ablaze with the colour of their fruit and foliage. These shrubs, botanically known as euonymus, shake off their previously plain appearance, as the leaves burn red and purple. It is, however, the bright, jewel-like fruits that gleam in misty hedgerows. In spinning cascades of pink and orange, they create droplets of pure, bright colour amid the drab branches of other deciduous shrubs. These fruits persist like hot embers long after the foliage has fallen.
A feast for birds
The fat seed capsules are divided into four plump symmetrical lobes like miniature lanterns. These split to reveal glossy orange, rounded fruits that descend from their covers and spin in the breeze. As they ripen and become more prominent, the colourful seeds provide a valuable food source. Persisting well into winter, birds feast off them through the coldest months.
The birds are attracted by the orange fleshy seed coat, with its high-calorie nutrition. Inside the coat the true seeds remain intact after being eaten. Because of this, they are able to make their way through the birds’ digestive tracts to be deposited far away from the parent plant. This is an exquisitely balanced natural relationship. It supports native birds, helping them to survive through winter, while the spindle tree is able to propagate itself throughout the countryside.
The native Euonymus europaeus is such a veritable larder for birds that it will often be aggressively defended by robins making it part of their territory. For this reason,
it is known as ‘robins’ bread’ in some areas of the country.
The fruit is poisonous to humans, as are all parts of the plant. The toxic berries, however, have been put to good use. One traditional remedy for head lice involved applying the crushed berries to the scalp. Referencing the plant’s poisonous nature, the name ‘euonymus’ may originate from Euonyme. In Greek mythology she was the mother of vengeance-wreaking goddesses, the Furies.
The bright fruits are often initially seen dangling below a mantle of colourful leaves. Before it falls, the spindle tree’s foliage has one of the most impressive transformations in the British landscape. It turns from an unobtrusive dark green to a bright pinkish red with splashes of purple and hints of orange.
‘Red Cascade’, a cultivar of Euonymus europaeus, has the brightest and perhaps best colour for this time of year of any plant. A spreading shrub, it reaches 10ft (3m) across and 8ft (2.5m) high. The scalloped leaves gradually turn deep red, starting at the midrib and spreading to the leaf edges. Before the metamorphosis is complete, the leaves take on hues of pink, orange and purple. ‘Red Cascade’ bears plentiful fruit, the branches bowing under the weight.
A lesser-known characteristic of spindle trees is just as fascinating. A close look into the criss-crossing mass of leafless winter branches and the ‘winged’ outline of the straight stems becomes apparent. The branches develop four wings of corky bark, which if cut through have a cross-shaped silhouette. This feature is most prominent on Euonymus alatus, known as the winged spindle. Originating in Asia, it grows to 10ft (3m) in height, gradually spreading to a similar width. With age the bark of the main stems may become fissured, adding to the unusual and sculptural winter outline of this plant.
A limestone lover
The native European spindle, Euonymus europaeus, thrives on alkaline soils and is common on the chalk downs of southern England and on limestone hills and vales. Preferring full sun and freely draining soils, it is tolerant of winds and hard frosts. While it can be found in the shrubby lower canopy of ash, beech or yew woodland, the leaves will be at their most colourful in an open, sunny position. The one situation it will not tolerate is boggy, waterlogged ground. In its natural habitat a spindle tree may live for over 100 years.
Once a very common hedgerow plant, a campaign of grubbing out in the 1970s has left it a rarity in the wild. The spindle tree was thought to harbour crop diseases and pests, especially black bean aphid, which is a major pest of vegetable crops. There was little evidence that euonymus was a truly significant threat to farming.
Now the native plant is spreading in gardens, where it is an easy-to-grow, highly ornamental shrub.
Where to grow in the garden
Ideally, spindle trees are grown where there is an unobstructed view of them in winter. The centre of an island bed is a good location, where its summer foliage offers a useful green foil for tall flowering herbaceous perennials. A winter border with bright-stemmed winter dogwoods Cornus alba, Cornus sericea and Cornus sanguinea is another good site.
There are over 170 species of euonymus around the world but just a handful make suitable garden plants. Euonymus europaeus prefers alkaline soils, but will also grow well in neutral or slightly acidic ground as long as the soil is free-draining.
It is one of the easiest shrubs to maintain, growing in full sun, part shade, sheltered or exposed situations. It is a tough plant that can be used to provide a windbreak, particularly when grown with other wind-tolerant trees such as hawthorn and dog roses. With its abundant food, it is an excellent choice for a wildlife or nature garden.
‘Red Cascade’ is one of the best cultivars of E. europaeus for the garden. Its colour and fruit has earned it an Award of Garden Merit from the Royal Horticultural Society.
Euonymus planipes is another good spindle tree for the garden. Displaying some of the most dramatic winter colour, it grows to 10ft (3m) high. With pinnate leaves reminiscent of an ash tree, it has a vase-like shape that spreads upwards and outwards from a narrow base.
Euonymus alatus ‘Compactus’ is an ideal shrub for less spacious gardens, reaching only 3½ft (1m) in height. With the same distinctive winged wood as the larger E. alatus, it makes an attractive, smaller sculptural winter plant.
Spindle trees need little work. They form a naturally balanced and well branching framework. Little pruning is required, removing only dead, diseased or crossing and rubbing branches, or branches that are growing in an awkward place. Any pruning is done in late winter or early spring before weeding around the base. The tree will then benefit from a mulch of well-rotted garden compost.
The spindle tree is a fascinating plant, valued for its unique aesthetic qualities, wildlife-friendly properties and its many practical uses. It deserves a home in British gardens where the bright fruits and colouring leaves welcome the changing of the seasons and feed hungry birds.
Words: Melissa Mabbit Photography: Alamy