Holly's Summer 2017 Newsletter
The star jasmine, the wisterias and the jacarandas – even more brilliantly blue after our dry Spring – have finished. The roses are at their peak, and the frangipani are promising a performance of holiday colours. Welcome to my Summer Newsletter.
As roses are filling our gardens with their beauty it's time, perhaps, to relate their complicated history. Many rose experts date old, or Heritage, Roses as those bred before 1859, when the first Hybrid Tea, the French 'Victor Verdier' was introduced to the gardening world. Celebrated Australian rosarian, David Ruston, has said, however, that Old Roses are all those that appeared before 1940. You see, in plant breeding, and where crossing and hybridisation occurs naturally, there are no absolutes. You can see Ruston's Roses, at Renmark, in this image.
Before the modern roses, with their repeat-flowering habit, burst onto the horticultural stage, there was a group of Old Roses - the Portlands, Bourbons, Noisettes, Hybrid Perpetuals and the Tea Roses - that were central to the story of the rose. All display the genetic makeup of the China Roses.
The Tea Rose is the result of a cross between 'Hume's Blush China' and 'Park's Yellow Tea Scented China' (two of the original four China Roses) with various of the Bourbon and Noisette Roses. Success came first in 1835 with 'Adam', a very double latte-coloured Tea Rose bred in England.
With their DNA from the southern part of China, the Tea Roses are the choice for those who garden in the more humid parts of this country. Tea Roses are repeat flowering, with thick, shiny, large petals and beautiful flower buds that have a high, pointed centre.
The luscious, pink to cream 'Marie Van Houtte' is a sprawling, climbing Tea Rose, as is the golden 'Lady Hillingdon,' with her blooms that hang down on red stems. They demand good air circulation and will thank you for growing them on a pergola.
The Tea Rose is one of the parents of the modern Hybrid Tea, along with the Hybrid Perpetual (itself a combination of several different classes), which provides hardiness, large flower size and thick, shiny, large petals, vigour, deep colours, strong scent and, most importantly, remontancy.
Hybrid Teas are perhaps the best known of all the classes of rose. It was the French breeder, Jean-Baptiste Guillot's breeding of 'La France,' in 1867, that firmly secured the place of the Hybrid Teas on the rose family tree.
Hybrid Tea rose bushes are upright, with none of the romance of the Old Roses, nor the voluptuous form of the Teas: they are valued, however, for their repeat flowering habits, their hardiness and their fragrance.
The loveliest of the older Hybrid Teas include the so-elegant pink 'Mme Abel Chatenay.' Raised in France in 1895, she is a cross between the Tea Rose 'Dr Grill' and 'Victor Verdier.' The gorgeous, climbing 'Lady Waterlow,' bred in France, was released in 1903 and bears very fragrant salmon-pink blooms. An early single-flowered Hybrid Tea, 'White Wings' with its dark green foliage and chocolate-coloured anthers, remains as popular today as when it was introduced, in the USA, in 1947.
Newer Hybrid Teas include, in the whites, 'Elina', a perfectly shaped, very scented cream rose with very long stems. For an informal hedge you might team the very hardy 'Apricot Nectar' with salmon-coloured 'Just Joey': it's a combination that's hard to beat.
Hibiscus, which, like frangipani, shout Copacabana sunsets in summer, belong to the Malvaceae family.
Flowers, which unfold in whites, creams and blush pinks, bear five overlapping petals arranged around a central column of fused stamens. Most species of hibiscus are evergreen, with leaves that are toothed or lobed. They thrive in sandy, neutral to slightly acid soils, and require full sun to flower well: most don't tolerate frost. Hibiscus are not fussy, but are heavy feeders. Prune occasionally to maintain the desired size and shape, remove congested branches to improve air circulation, and then apply a complete food. Among the few pests to watch out for is the tiny black hibiscus beetle, which will chew holes in the buds, but which can be combated with Confidor.
Like many plants, hibiscus can be pruned hard to create a smart hedge: in Hawaii you'll see double or triple hedges that feature the clear red, single flowered H. kikio. Or, let them grow freely to bend and sway over a lower hedge that is clipped to a calm green.
The best known of the genus in Australia is probably Hibiscus rosa-sinensis, a medium sized shrub from which thousands of varieties have been bred. Flowers, which might be single or double, range in size and colour. Cultivars with names like 'Hawaiian Sunset', 'Surfrider', 'Blue Bayou', and 'California Girl' provide more than a hint as to their preferred environment.
The sea hibiscus, H. tiliaceus, growing naturally throughout the coastal regions of the Pacific, in Hawaii and tropical Asia, is a good choice for gardens struggling to withstand the onslaught of salt winds. This species grows to a sprawling tree that can be planted in multiples as a first defence, and to create a microclimate for treasures less tolerant of brutal conditions. The yellow flowers bloom among large, heart-shaped leaves. Similar in form and flower, H. diversifolius is a tough native of the Top End, and will also cope with salt winds. Swamp hibiscus (H. coccineus) with its distinctive, slim petalled, coral-red flowers, is native to the waterways of Georgia and Florida.
Indigenous to China, the cotton rose, (H. mutabilis) flowers in single or double, blooms that are reminiscent of peonies: it grows to about 2 metres. The charming coral hibiscus, also known as the fringed hibiscus, H. schizopetalus - native to East Africa – should be planted where you can look up to its delicate, lantern-like pendulous flowers with their recurved, frilled petals. The Norfolk Island hibiscus, Lagunaria patersonia has beautiful flowers, but the seeds can cause skin irritations.
The national flower of Korea, H. syriacus, also known as the rose of sharon, is deciduous in cooler climates, and will tolerate light frosts. It is a useful landscaping species, with single or double, paper-fine flowers in a range of pastel colours, from the white to lavender, to the cerise-splashed 'Woodbridge.'
It's amazing how innovative some gardeners can be, particularly those who garden in small spaces. We've talked about employing any vertical surface, including walls and fences - and the air - to grow climbers, shrubs and trees for different effects, and uses. Apartment dwellers are even (after advice from structural engineers) creating flourishing gardens on rooftops: oases in the sky.
It seems we've been hearing the term 'green walls' for just a few years, but gardeners have been creating living walls for centuries. Whether climbing species are planted in the ground on a frame separate from a building, or plants are grown in clever soil and water systems hugging a house, a living wall is environmentally sound, utilitarian and beautiful.
The green wall at Madrid's Atocha Railway station is famous. In Paris the designer Andree Putnam has installed a living wall in the Hotel Pershing Hall. There's a contemporary house in Venice, California, that is now covered in succulents planted on cement walls that support an irrigation system erected against a protective membrane: the house looks like a colourful cube. A system of pockets holds soil and a meticulously regulated capillary system allows for water collection, filtration and recycling. Today you can purchase completely integrated living wall systems.
While increasingly popular in recent years, the living wall is, in fact, an ancient construct. The earliest living walls were surely the fabled Hanging Gardens of Babylon, created almost 3000 years ago, supposedly by King Nebuchadnezzar (ruled 604 – 562 B.C.), between the Tigris and Euphrates rivers, about where Basra is today, in present-day Iraq. In his discussion of what he calls the 're-presentation' of ideas and cultural themes in gardens old and new, landscape historian John Dixon Hunt explains that the Babylonian gardens, down on the hot plains, were constructed to trigger 'recollections of faraway mountain sites.' These gardens, he notes, have been referenced by today's designers, from the hanging gardens of the Trump Tower, to those at Paris' Gare Montparnasse.
As well as being beautiful the Babylonian gardens - a series of stepped platforms - fulfilled practical roles like natural air-conditioning and dust control. Their arrangement prevented soil erosion and water wastage. Today such passive, low-impact installations also reduce noise and air pollution, and, like a tree canopy over a roof, a green wall will reduce heat by more than ten per cent. In Australian outback gardens vine covered structures have long served the purpose of preventing dust from invading the homestead. A living green façade is cooling, particularly when sprayed with water.
You can employ almost any plant in a living wall, except, perhaps, climbing species which would take over from smaller-growing plants. Some plants seem determined to flourish with very little space and minimal soil: think of rhododendron growing on a cliffside, 4000 metres up in the Himalaya. Think of the epithetic orchids that grow high up in the jungle canopy in the Central Highlands of Papua New Guinea. And the English are masters at planting out craggy walls, or less than perfect steps, with species that flourish in no soil, shoehorning tiny plants into the smallest of cracks.
In the wall pictured here, at the International Garden Festival at Chaumont sur Loire, hostas, ferns, heuchera, euphorbias, primulas, begonias and even Mexican orange (Choisia ternata) were all squeezed into panels that divided the large kitchen garden into manageable spaces. You could also employ a cornucopia of herbs, or leafy vegetables and cherry tomatoes, or easy-going species such as pelargoniums, dianthus, arabis, violas, succulents like sempervivums and echeverias, or cactus. History is repeating itself.
TO DO IN THE GARDEN
It's time to prune your roses, if you live in an area prone to late frosts: you did't want the plant to shoot too soon, when there was a risk of damage to young, fresh growth. Begin by removing any diseased or damaged wood, right back to a healthy joint. Remove any crossing branches that might rub on others, creating wounds that will encourage disease. Remove old wood to ensure the continuing development of the shape you want, to encourage a succession of young and healthy shoots, and to create a shrub open enough to allow air to circulate.
Fertilise roses after pruning with aged poultry manure, and mulch well. And take care if using glyphosate-based weed killers near roses, as they are very sensitive to this poison, which can be transmitted via the roots, resulting in curled and falling leaves, deformed flowers, and worse.
It's also time to hard-prune wisteria that has finished flowering, back to two fat buds. And you can prune camellia to allow air to circulate and to improve structure and shape: a gardener in Harrietville advises to prune so that a small bird could fly straight through. You might use prunings to create tee-pees and tents to support climbing vegetables.
When using all pruning equipment, including secateurs, ensure the holding arm is gripping the section of the plant that will be discarded: hold the pruners so the cutting blade is on the section of the plant that will remain on the bush. This ensures you don't bruise the remaining wood, inviting disease. Dip pruning equipment into a disinfectant bath between plants so that any infection won't be spread.
THE EDIBLE GARDEN
In warm areas you can plant tomatoes, particularly the tiny varieties like 'Tommy Toe'. Friends in frost-prone climates wait until after Christmas to plant.
A warm season vegetable – although botanically a fruit - the tomato (Solanum esculentum) is a member of the poisonous Solanaceae family, along with the potato, eggplants and chillies. Native to South America, tomatoes were transported first to Spain and Italy, then travelled to Russia; then North America, where, in the 18th century, many new varieties were bred. Most tomatoes are, of course red, but they also come in pink, apricot, yellow, purple and black; even striped.
There are many reasons to grow your own tomatoes. Firstly, nothing tastes better than a just- picked, home grown tomato! As well, studies in the United States have reported that levels of flavonoids - an antioxidant linked to reduction of various illnesses - are higher in organic tomatoes.
You can bake just-picked tomatoes – up to 3 hours in the slowest of ovens - to serve with basil leaves from the garden, crumbled goat cheese, and a drizzle of the best olive oil. It will be the perfect accompaniment to a mango and seafood salad. For me, Christmas lunch would not be the same without platters of these vine ripened, slow-baked, tomatoes.
As basil teams so well with tomatoes, and assists in combating the plant's pests and diseases, grow them together. Chillies, which enjoy the same conditions, can be planted close by.
This month you might also plant out punnets of brown onions, carrots, rainbow chard, and a variety of lettuces, including butter lettuce. Plant more beetroot so that they can grow quickly in the heat to be roasted in orange juice and served with chopped herbs. The eggplants are flowering, the capsicum are growing well: the chilli plants are covered in fruit, as are the strawberry plants. I am watering everything with a weak solution of fertiliser each week, so that they will mature quickly, ensuring sweetness, particularly among the leaf vegetables.
And, as I said in Spring, I've been told that soaking shop-bought vegetables in a teaspoon of white vinegar added to a litre of water will remove any residual pesticides that may have been used.
PESTS AND DISEASES
Phytophthora cinnamomi is just one of a range of soil-born fungi that can cause die back in ornamental and edible plants. Collar rot, or root rot, is another soil-born fungus, encouraged by mulch applied too close to the trunk of a tree or shrub, or by poor drainage, and, at worst, will ring-bark the plant. Symptoms to watch for include yellowing and dying off of leaves and sap oozing from the trunk. Another fungus, Glomerella cingulata, enters plants through wounds, and also causes die-back.
Treat the soil by drenching with a systemic fungicide and spray foliage with Yates AntiRot, another systemic, low toxicity fungicide. Prevention is better than cure, of course, and you can start by maintaining good gardening practices, including keeping mulch clear of the trunks or stems of plants. In heavier soils, where drainage might be poor, add a soil conditioner such as dolomite, or a fish or molasses-based product to enhance friendly biology to improve plant health. Sterilise pruning tools between plants to help prevent the introduction and the spread of disease between plants.
Armillaria is a group of fungus, most commonly the honey fungus, (Armillaria melea), and should strike fear into the heart of every gardener. Identified by its tangle of black, shoe-lace- like long black cords - rhizomorphs – it spreads quickly through the soil, under bark of trees and shrubs - often identifiable by a white, fan-like fungus underneath the bark - and on their roots. Its symptoms - on a variety of trees and shrubs but also on plants like strawberries and raspberries - include wilting, curling and fall of leaves and even the death of the plant. You'll need to remove and destroy the affected plant as quickly as possible.
Not always a death sentence, bracket fungi are the fruiting body of a decaying fungus, and appear as flat mushrooms – or frisbees - most often embedded on a tree trunk, in horizontal layers. Often orange with green markings, these fungi indicate serious decay within the plant. You need to cut away and burn affected sections of the plant.
Roses will struggle if not grown in the hot and dry conditions they love, and may succumb to a range of diseases, including Black Spot. You can combat by spraying weekly with a mix of 3tsp bicarbonate of soda, 2tsp pest oil and 5 litres of water. Powdery Mildew, most common on roses and grapevines, particularly in humid climates, can be treated with Yates Fungus Gun, a systemic fungicide spray based on Myclobutanil, effective against mildews, black spot and rusts on roses, and other ornamental plants like hydrangeas, geraniums, hollyhocks and sweet peas. Organic gardeners also swear by milk, diluted in water 1:10 and sprayed over leaves. Rose Scale is a small white scale that crusts onto stems of the plant. Treat by spraying PestOil, which is registered for fruit trees and ornamentals and is also used for controlling citrus leaf miner. (You can read more in my book, Seasons in My House and Garden.)
Yates also advises that Scale can be controlled with the Confidor Tablets: insert 5cm deep in the soil, in the root zone, and water well. Don't forget you can join the Yates Garden Club for free advice on all garden topics. Go to www.yates.com.au/garden-club
The best management, however, is, again, to choose plants suited to your climatic conditions.
A few years ago a group of mothers from Cranbrook School in Sydney – we called ourselves the Cranbrook Gardeners – escorted a busload of friends to the glorious gardens of Mount Wilson, 2 hours west of Sydney. The day was organised to raise funds for a stainless steel and copper eucalypt, known as The Tree Project. The sculpture is an initiative of The Australian Blacksmith's Association (Victoria), as a tribute to, and support for, those devastated by those terrible bushfires of February 2009.
A eucalypt was chosen as a symbol of Australia and of regeneration after fire, representing the Australian spirit, compassion, strength and renewal. Leaves, a mix of eucalypt species, were forged by metal artists around the world. Some were sponsored in memory of loved ones lost.
The Cranbrook Gardeners raised funds for the tree trunk, and the completed tree has been erected in a memorial park in Strathewen, a tiny town in the shadow of Mount Sugarloaf, close to Victoria's Kinglake. You can view more pictures on www.treeproject.abavic.org.au
Here is a recipe for an alternative to Christmas pudding, also from my Seasons in my House and Garden; it's my daughter, Olivia's recipe for the ever-popular Tiramisu. Make it the day before serving to allow the flavours to really develop.
2 eggs, separated
Whip egg whites to stiff peaks.
There is also a great recipe for Christmas cake – its secret ingredient is dark chocolate! - and instructions on how to ice it, in Seasons in my House and Garden.
And, of course, a very Happy Christmas to you all.
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