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Observed during May 2011

24/5/2011

Pendulous panicles

a multi stemmed deciduous shrub native to Western China. Huge pinnate leaved foliage, comprising a variable number of leaflets (13 – 25) develops, forming a dense canopy of foliage. The plant is easily rejuvenated by cutting out stems at ground level. Fresh sucker type growth rises up almost immediately soon replacing the status of the plant.

In the wild it colonises streamsides in degraded primary evergreen forest of western China at an altitude of 2200 – 2500m. A member of the family Lardizabalaceae which also contains the climbing genera Holboellia and Akebia.

Elegant individual flowers are held sprayed down a long central stalk. The sepals are a green/yellow colour elongated to a definite point. The pendulous panicle is worth admiring for its elegance.

17/5/2011

A Balkan beauty

Weather and climate have colluded this year to ensure a magnificent flowering season. Mature trees have excelled in their flower production this year and currently Fraxinus ornus var. juglandifolia is awash with panicles of miniature scented white flowers. The panicles extend to 200mm in length; each individual flower is composed of 4 off white petals. These appear after the foliage has flushed and expanded. The pinnate leaves resemble those of Juglans and are held in opposite pairs colouring yellow during autumn.

Growing on the hillside where the shallow free draining soil is not the best medium for Fraxinus. Never the less this specimen dating from 1892 has a healthy broad rounded canopy. A native to the Balkans through southern Europe and into Asia.

10/5/2011

Rock solid blooms

Four and a half pages of tight text indicate the importance that WJ Bean placed on this species of tree Paeony, P. suffruticosa, in his book “Trees and Shrubs Hardy in the British Isles.”

A deciduous woody plant that makes two metres in height as the extension growth from the terminal bud develops over the years. Not a plant for the front of the border during the winter months as the woody growth is not of good form. During the growing season the foliage and the spectacular flowers more than compensate. The plant growing in the woodland area is one of Joseph Rocks collections and as near to the type Paeonia suffruticosa seen in herbarium specimens.

In full bloom just now, slightly scented, the large off pink petals are marked on the inner surface by a maroon blotch. These are large blousy flowers that catch the eye and the imagination. They are plants to be grown and coveted if you have space in your garden. They prefer a moist yet free draining soil out of direct sunlight.

“The Moutan Paeony” is a native to China and searched for by many of the prominent plant collectors who in previous centuries have introduced the plant to the west. Reginald Farrer commented when he found specimens flowering in the wild they were “fragrant as heavenly roses.”

3/5/2011

The true Quince

Chaenomeles japonica is often referred to as Quince. This common name should be reserved for Cydonia oblonga.

The fruit of both do however make a very fine jelly; delicious with cold meats and cheese.

Cydonia oblonga is a deciduous small tree that forms a wide much branched canopy. It flowers but does not fruit with us in Edinburgh. A native of the Near East and Central Asia where hot summers guarantee a good set of the scented fruit. Conversely, to initiate flower buds a winter temperature of -7oc or below is required

Here we must be content with the flowers, when loosely rolled in bud resembling a raspberry ripple ice cream cone. The open flower with delicate pink venation on white petals has a slight and unusual scent.

The foliage of soft downy young leaves is, unfortunately, prone to infestation of mildew and subsequent die back.

Observed during May 2010

4/5/2010

The most magnificent Malus

During the early 1900's exploring the thickets of Sichuan in SW China Ernest Wilson introduced Malus hupehensis. Now a broad multi-stemmed tree with an eight meter wide canopy. Full of delicate pink blossom. The buds open from deep pink to blush white.
Wilson considered this to the finest deciduous flowering tree he introduced.

Each flower held on a long (40mm) stalk increasing the spread of colour through the tree. On a cold breezy day the hope of appreciating the delicate scent given off by the blossom is negligible; but with a touch of warmth from the sun the faint musky scent will be noticed.

Initially classified as M. theifera as the young leaves were known to be picked and infused as a tea in China.

11/5/2010

Picture perfect Paeonia

With the sun on the petals this Paeonia coriacea is seen at its best. Each herbaceous shoot bestowed with flower. A native to Morocco where it was collected from a valley slope of limestone, west of the Rif Mountains at 1495m. An area of high rainfall it associates with Cedrus atlantica, Taxus baccata, Daphne sp., and Berberis sp.

The pink petals surround an explosion of yellow anthers interspersed with three pink styles appended atop their stigma; resembling the two sections of a scallop. The stigma is curled as a shepherds crook loosing this delicate shape during maturity. Similarly; as the days progress the colour drains from the petals leaving the pollen shed from the anthers visible.

A strong plant reaching 1m in height and similar spread. Just now standing unsupported. As with most Peonies it will splay apart as the growing season progresses. Ideally, a discreet support framework should be in place before this happens.

18/5/2010

Seals and shrimps in the season of phenomenal growth

Spring; and the ground flora greens up. Growth during the month of May is impressive; leaves seem to double in size during the hours of daylight. The prolonged cool start to spring this year has delayed the mad rush to set out bedding and early veg plants in the hope of early establishment and a longer season of flowers. Those that have been rash enough to do so have seen disappointing results.

Gunnera manicata from the swamplands of South America forms massive herbaceous clumps. The above ground mass develops from the basking seal shaped brown stem to rapidly expanding leaf growth. During May the leaf stem becomes covered in spines. By mid summer the leaf diameter can be in excess of two meters.

Look at the flower spike, the top is awash with long white anthers protruding as bean sprouts. The female flowers are at the bottom half of the conical spike receptive to pollen as it falls.

At the other end of the scale Darmera peltata, also herbaceous, is shooting from the rootstock. The fresh growth resembles a mass of shrimps on the surface of the soil.

At the same time a flower spike rises to one meter. Having a well proportioned rounded inflorescence, best in bud, when the pink colour is most attractive. The flowers, once open, soon loose their, by then, white petals. As these fade watch the phenomenal rate at which the leaves expand. As with the Gunnera, also preferring a moist root run.

25/5/2010

Ravaged by winter; cherished by spring.

Well here we go harping back to the winter after the warmest weekend of the year.

Winter has left its mark on the Chilean native, Acrisione cymosa. Notice the frost crack on the bark and shoot tip die back through the crown. Then comes the more mellow conditions of spring, growth shoots away and large inflorescence of yellow composite flowers cover the plant.

This year's display is much reduced from the mass of corymbs that covered the plant in May 2009. When you consider the parent plant was growing on the margins of the Valdivian rain forest at 558 metres; to put on good quality extension growth with leaves that have a silvery tinge to the underside is exceptional. To produce good sized heads of flower shows it is also benefitting from the microclimate it now finds itself in, tucked in front of a south facing wall.

In the Gateway Gallery on the first floor of the John Hope Gateway are images of Plants from the Woods and Forests of Chile. This runs until 18th July, it is part of a project to illustrate 70 Chilean plant species that represent the biodiversity of the woodlands and forests of Chile. The Acrisione cymosa has been drawn by Isik Güner, one of three Turkish artists involved with the project.

Observed during May 2009

1/5/2009

A wall of colour

Outstanding. Just one word that captures the quality of the Rhododendron display this year. Previously I mentioned a subspecies of Rhododendron arboreum. A hybrid affiliated to this species, R. aff. arboreum hybrid produces a wall of colour covered in mauve trusses of bloom to a height of five metres. Looking behind the wall of vegetation reveals a two metre layer.

The plant at one stage, several years previously, becoming top heavy, collapsing, then sending up skywards shoots that have matured into the growth seen today.

Next to this plant is a more delicate flower, pink in bud to unfurl white, R. bureavii from Northern parts of Yunnan Province, S.W. China.

The leaves of this species also attract attention. The reverse is covered evenly and thickly in brown indumentum.

The flowers of R. yunnanensis (also from S.W.China and N.E. Myanmar) release a heady perfume. This in itself is worth visiting the Garden for. The area around this plant is saturated with this most compelling scent.

Representatives of the collecting prowess of E.H. Wilson and Joseph Rock are worth hunting for. The blue of R. augustinii ssp. augustinii is cascading through the mature plants. Look into the individual flowers of Joseph Rock's, R. augustinii ssp. hardyi. White petals with the top inner lobes marked decisively green. These spatterings of colour are unusual and worthy of comment. Designed to entice pollinators to the flower, in both, the flower parts flail out wildly.
So, for a visual feast of walls of colour, banks of perfume and intricacies of design; walk through the north or east gate and enjoy the experience.

5/5/2009

Paeonia with a problem

Paeonia mascula; with a wide geographical range; Mediterranean to S.E. Asia, this herbaceous species produces carmine red flowers that are stuffed full of yellow anthers. A worthwhile member of the genus to cultivate. Depending on provenance flower colour can range white - pink - red. There is wild collected material from Cyprus represented in the collection.

Paeonia wilt, Botrytis paeoniae, can be seen in the attached image. Grey mould colonises soft brown areas of rot which occur at the base of the stems. This grey mould will then gradually colonise all plant surfaces. Remove and ideally burn all infected vegetation, ideally scraping off the soil in the area where the spores may have dropped to. In autumn good hygiene will prevent the disease from carrying through to the following year.

8/5/2009

Iris's handkerchief

Iris iberica var. elegantissima one of the showiest of the Oncocyclus group of Iris. This naturally occurring variety is found in N.W. Turkey and into neighbouring Iran.

The seed parent of this bulbous Iris was found growing on dry rock strewn slopes at 2200m near Erzurum in Turkey. In full bloom the white standards resemble handkerchiefs (cotton of course) strewn about.

These broad creamy white standards are c. 100mm across. Purple streaking and mottling at the base develops into striations then a pepper dusting around the centre tip.

The two falls drop vertically from the centre of the flower. These are scallop shell shaped with white markings on dark mauve colouration. This is a must see plant displayed in the alpine house and with a second bud yet to open, extending the opportunity well into next week.

12/5/2009

Intoxicating scent seeking wall space.

Elytropus chilensis a woody evergreen almost unnoticed as you walk through the Chilean plant collection to the north of the Front Range. Flowering profusely tucked beneath other shrubs but in desperate need of a wall to climb. The long scandent growth is thriving in this shaded ground hugging situation to the self satisfying point of producing flowers at each leaf axil of the previous year's growth. In Chile it grows in the shade of rain forest canopy on the sides of the coastal mountains up to the edge of the tree line at c. 2000 metres.

The small leaves have a glossy upper surface and are set opposite each other on the stem. The flowers hang down from these axils, five petalled, tinted pink on the lower inner surface. The scent drifting out is dismissed at first, but there is something intoxicating about the intensity of the smell. Well worth the walk to the north of the Front Range to sniff test.

From the microscope images the anthers are covered in minute bristle like white hairs, a secondary group of hairs can be seen at the base of the petal chamber. Notice the globules of nectar which are contained within the base of the flower parts. Observe the translucent, almost ice crystal, colour change at the tip of the anther. The fascinating detail and intricacies of design within the plant kingdom are revealed through the lens on the microscope.

15/5/2009

Visible from space

Descending into Edinburgh airport and picking out landmarks is generally the way to pass the time in anticipation of landing in the capital.

On a return flight our Director of Horticulture anxious to confirm the Garden was still here was nonplussed to observe a mass of yellow at its centre. This is the young foliage of Quercus rubra "The Red Oak", introduced from Eastern North America in 1724.

The tree is set to the north east of Inverleith House and the broad spread canopy of foliage visible from many points in the Garden. There is a cultivar 'Aurea' and this may be a representative of it. As the season progresses the foliage turns green and as a finale produces desirable autumn colour.

19/5/2009

Salad days

Magnolia acuminata, also known as "The Cucumber Tree". It takes this common name from the shape and appearance of the fruit which swells to resemble a cucumber after petal fall. The flowers are not big and blousy as in other members of the genus but merge with the spring foliage. There is a green metallic sheen to them in the sunshine. With a sweet, honeyed fragrance the flowers sit upright on the previous year's growth.

A native to eastern North America where it makes a broad specimen as a large forest tree to 30 metres height. In Canada it is recognised as endangered.

As a topical reminder to keep fresh salad appearing on the kitchen table; remember to keep up with the sowing of small amounts of seed frequently at this time of year. No amount of salt on a woody radish will improve its texture!

26/5/2009

The Himalayan Blue Poppy

A new planting of Meconopsis Hybrids can be seen in the woodland garden, one of the best being M. 'Slieve Donard'. This hybrid has an Edinburgh city pedigree dating from about 1935. Dr. Curle a former Director of the Royal Scottish Museum used M. grandis and M. betonicifolia as breeding parents; raising many seedlings. Some of these found their way to the long gone Slieve Donard Nursery, Co.Down, Northern Ireland. Here they were bulked up and the Slieve Donard form selected out and introduced to the trade. With us; flowering commenced in the middle of the month and has now reached its peak.

More detailed information on the nomenclature of the genus can be found at the Meconopsis Group website. The group are currently undertaking a revision of the genus, placing M. 'Slieve Donard' in the Infertile Blue Group.

As a contrast; planted near this group in the woodland garden is M. 'Marit' defined by its large white petals. Both cultivars mentioned send up flower spikes from a basal rosette of leaves. The clumps require splitting and dividing every 3 - 4 years. Appreciating a cool moist root run the addition of composted organic matter at planting will ensure sturdy growth and reliable flower production.

Established plantings can be seen at Dawyck Botanic Garden where it has long been planted along the banks of the Scrape Burn.

29/5/2009

Pin ‘n Pod

Foliage to appreciate in a woodland border is how I would describe the leafy growth produced by these two memorable Rodgersia species. Rough and robust. The images show the variable shades of green and bronze taken by these leaves.

R. pinnata with almost pinnate leaves. The 1990 collection made on the Chungtien Lijiang Dali Expedition (CLD) to Yunnan Province, China has green leaves. Found growing at 3430m amongst Rhododendron on a steep hillside near Longquan Peak. Yet a 1961 accession to the Garden is decidedly purple. The cultivar ‘Irish Bronze' has foliage slower to develop but with a uniform deep purple colour. Flower spikes have good structural form and are covered in small pink flowers.

The favourite has to be R. podophylla; native to Japan and Korea with large palmate leaves. Strong uniform growth to 1.3m. This introduction was collected by Yuji Kurashige at 1200m in Honshu Province, Japan. If you have a soil that retains moisture in a shaded area of the garden then this is the one to prepare the ground for. Add organic matter at planting and once established top dress annually. The flower spike pushes out above the foliage to 1.6m gradually expanding to pagoda like form.