As observed in 2010
Scent from the Tropics
Solandra grandiflora has risen from ground level of the temperate lands house to adorn the railings of the warm weather walkway. This tropical liana is covered in tubular yellow flowers that exude a rich powerful heavy perfume. This strengthens and becomes more intense as darkness falls, attracting the Hawkmoths which pollinate this species. A strong growing plant requiring substantial supporting vegetation, or as with the specimen at RBGE, the railings on the warm weather walkway. In the wild it can meander for 15 – 30 metres.
Liana is a description of a group of tropical woody plants that use trees and other vegetation to reach sunlight from the forest floor. They grow up, through and over supporting vegetation binding tropical biodiversity together giving strength through tropical storms to weaker elements of the vegetation and facilitating access corridors through forests for wildlife by joining the canopy together.
The flower develops as a greenish yellow elongating bud with prominent veining. At maturity within the chalice shaped flower are dark striations that run to the depths of the corolla tube. Copious amounts of powdery white pollen drop onto this from the anthers.
Scuffle strips and bowed plants
A week of heavy snow and no real thaw has resulted in a build up of snow on foliage through the garden. Keep an eye on evergreens where the weight of snow may cause snapping of limbs and branches. Take a look at roofs of glasshouses and poly tunnels. Again remove excess build up of snow where possible. The structural integrity of some structures may be compromised by the additional weight of this dense white mass.
Alpines are snug beneath their blanket of snow. When the forecast deep cold and wind chill arrives as this month progresses the full benefit of a deep snow cover is realised. Low growing plants are protected from the worst of the temperatures beneath the white blanket.
Birds are desperate for shelter and a food source in this weather. This is when hedges and the relatively protected ground beneath show their value. Birds are able to pick through the leaf litter along the length of hedges scuffing the leaves about for grubs and bugs.
Low sun and silhouettes
With the snow still blanketing the land this is an ideal time to appreciate the silhouette of deciduous trees. At maturity the grandeur of forest trees dominates the landscape. This is a good time to remember succession planting. Within a garden or landscape, age diversity is important to maintain the tree canopy cover. Tree planting to preserve and manage this status should continue through generations each one benefitting from the thought and dedication of the one that went before. A range of species of many ages will moderate the climate within the Garden, filtering wind speed and providing shelter. Still struggling to think of a Christmas present? A tree may be the solution; help to plant it will be even more graciously accepted.
The images show mature Field Elm; Ulmus minor, Sycamore; Acer , Beech; Fagus sylvatica. Each with their own distinctive silhouette. Bark character differs in each; smooth and silvery in Fagus, deeply fissured in Ulmus and plated in Acer pseudoplatanus.
The shortest day dawns and we can hope the weather improves with increased day length. The country proverb that when the Holly is prolific with berries we will be in for a long hard winter has certainly proved true this year. The Ilex aquifolium through the garden is laden with berries. The plants are dioecious; male and female flowers on different plants. Welcome sustenance for the bird population when the soil is unavailable to peck through for grubs. Flocks of Waxwings have been observed descending on Rowan trees, Sorbus species, devouring the berries.
A vigorous Rose in the Chinese plant collection showing a proliferation of shiny orange hips is Rosa glomerata. Found growing on a steep north facing mountainside at c. 2420 metres in Sichuan Province, China. It climbs through deciduous woodland canopy composed of Sorbus, Acer, Lithocarpus, Pterocarya and Faxinus spp. to 8 metres.
Review of the year
The year opened with snow on the ground and saw a continuation of the longest unbroken freezing spell for several decades. The snow just continued to fall, blowing in on north easterly winds. When it turned milder the rain came and soil became waterlogged. The spring bulbs were late in flowering but as usually the wait was worth it and the display rewarded us.
1st March arrived to settled weather and bright sun but still an overnight frost. The month ended with overnight snow during the night of 30th March. Edinburgh became an island where all around roads were blocked and landslips closed the east coast rail route.
Late April saw the start of a highly floriferous blossom season. This combined with a long spell of settled dry weather really breathed life into the Garden with increasing visitors. The dry spring continued through June and into July prolonged the profusion of flowers in the Garden. Midsummer was magnificent, with the Gardens late opening appreciated by many.
At the end of June Aesculus californica produced long flower candles with a slight scent. It must have enjoyed the cold winter and dry spring. Collected as seed in 1991 these plants flowered for the first time in 2009, but that year, with a much reduced panicle size.
August monsoons swept through. Though there was a spell towards the latter half of the month when the front lawns showed signs of drought.
September gave a prolific crop of Mulberries, both the black Morus nigra, which were delicious and the smaller white, Morus alba, slightly bitter to the taste. 2010 was a prolific fruiting year in general.
First frost on the morning of Wednesday 20th October. Then a wet spell preceded the deep cold that arrived on the lead up to St Andrews day. The 200mm soil thermometer progressively recorded a lowering of the soil temperature as the frost got deeper into the ground.
The autumn colour was a little sporadic this year; many trees lost their leaves before developing full colour. This was noticeable in the Fraxinus and Sorbus species. A good spell of settled weather during the last weekend of October and the start of November made the colours much more appreciated.
The Davidia involucrata was laden with rounded seeds the size of golf balls. Hanging from long stalks at the tips of this season’s wood. These became visually evident from late November once leaf fall progressed. It was the first time I had noticed such prolific seed production on one of our trees.
As the year started with snow, so it ended. Snow covered all of the country in early December and this combined with freezing temperatures and fresh snowfall prolonged the covering, although sporadic, to the end of the month.
Best wishes for the New Year and may the deep cold and severe weather we have experienced lead to planting opportunities in 2011.
As observed during December 2009
The brightest berry of the season?
Sorbus commixta has the brightest berries of the genus; bright red in colour with a lustrous sheen. It does increase their appeal when the sun shines on them from its seasonal low angle. Native to Asia, from where seed has been collected in Japan and South Korea and introduced to the Garden.
A small tree at maturity with an open crown. The winter buds being distinctively elongated with a slight twist. Glabrous muted red in colour they are held close to the side of the old wood. Groupings of prominent white lenticels are visible at the base of the fruit stalk.
Student plots; cultivated and composted
As part of the first year of the HND Plantsmanship course the students are given a plot to cultivate; to sow and grow through 2010, producing a selection of vegetables and flowers.
The majority have now double dug their area, adding compost from the green waste the garden produces to the trench. An ideal way to build up the humus content of the soil; this in turn aids moisture retention and increases the soil life population. Feed the soil for it is the soil that feeds us.
A green manure and seaweed top dressing show alternative ways of improving soil structure, texture and fertility. The plot in the foreground, roughly dug will benefit from the frosts experienced in the past week. The alternate freezing and thawing action breaks down the clods, followed by a light rake in spring will produce a friable seed bed.
Black leaves for dark days
The planting of Ophiopogon planiscapus 'Nigrescens' near Inverleith House is a significant splash of black. Look closely and the few strands of reversion to green foliage show up. Ideally as time allows these plants should be teased out from the clump to give a purity of colour. There are plantings of the species itself in the rock garden where the leaves are green. This is a native to Japan.
This cultivar is of garden origin and is one of the best plants to grow for contrast to mainstream planting. It is loaded with knotted masses of berries which are equally as black as the narrow strap foliage. The roots have fleshy nodules attached that retain water enabling the plant to survive through periods of drought.
The ideal berry for a seasonal tipple
It is known to grow in boulder fields in Yunnan Province amongst degraded forest with Abies and Larix at 3250m.Seed from these plants has germinated and young plants can be seen growing at Dawyck.
A blue tinge is evident through the foliage which hangs with a pendulous habit. The aromatic wood is used as incense in Buddhist temples through Bhutan.
Berries are evident on this year's growth ripening over 12 - 18 months to glossy black with a dry flesh. It is the immature green berries of the Juniper that are used as the primary additive to flavour gin.
The resinous flavours reduce towards maturity and on drying. Although it resembles a one seeded berry, it is in fact a cone. The fleshy scales remain fused together and can be identified as such on closer inspection.
Review of the year
A year of snowfall; snow fell of a quality not seen in Edinburgh for several years. On the 9th February; we even resorted to attaching the snow plough to the front of the tractor. It was six years previously when we last used the snowplough in the garden.
Following the melt we were rewarded with the best flowering season for Rhododendron, Magnolia and Bluebells for many years. Apart from a couple of mornings early in the season when blossom was damaged by early morning sun on frosted plants there were no other spoilt blooms.
The season continued with herbaceous flowering of an equally high standard. All in all the best flowering season that I can remember - ever.
May was cold and dry; the soil took a long time to warm up but the weed seeds germinated just to prove there is life in the soil. Then the 29th dawned, the sun rose at 4.30 am and burnt a continuous groove in the sunshine recording card until a cloud passed at 6.50pm and then shone briefly again for a further 15 minutes.
The following day this was beaten; continuous sunshine from 4.30am until 7.20pm with a maximum temperature of 24.9oc. Was it this combination of weather that allowed the production of much cuckoo spit; evident from late May through June?
Following the max temp of the year on 2 July of 29.9oc, (only beaten by the 5th August 1975 at 30oc), the summer became warm and humid with the usual torrential rainfall we now expect. Following 36 hours of continuous rain during August a Betula utilis collapsed with a rotted root plate. A changing climate? This is the fourth year now where the European monsoon drenches us through August with torrential rain brought in by westerly winds from the Atlantic. Thereafter we then experience long dry Indian summers. This year lasting well into late October.
The weather pattern stabilised in September. Autumn colour started very early with good leaf tints from mid September; Betula, Sorbus and Euonymus leading the way.
The first V formation of Geese passed overhead, flying south, on the last day of September. The first white ground frost in the morning of Saturday 17th October added ambiance to the exceptional autumn colour.
November was wet. The highest November rainfall for two decades. In total 125.6mm of rain fell throughout the month. Since 1990 only November 2000 produced more than 100mm of rain (103.3mm). The ground was sodden and still is. It makes horticulture difficult to practice when soil becomes unworkable with this level of rainfall and unpleasant to work outdoors.
The Garden experienced the first snow of the winter on 17th December and then it just kept snowing. It is unusual to have such a prolonged snowfall at the end of the year and makes for a long winter. Deep cold will sort the wheat from the chaff with regard to survival of dubiously hardy plants. The reliable Winter Jasmine, Jasminum nudiflorum is a winner no matter what the climate throws at it. This is the one to draw the wallet from the pocket when contemplating a purchase. Other members of the genus may exude a delightful perfumed scent but will not flower with such reliability.
With the soil sodden and largely unworkable; what to do? Concentrate your mind on herbs. How many times do we realise at the last minute that a selection of herbs is essential to add flavour to the Christmas dinner? How many times do we reach for the dried shop bought version? Pulling long forgotten bottles from the back of the cupboard. Now is the time to draw up the selection of herbs to be planted in 2010 within easy reach of the kitchen door or in the window box on the kitchen window ledge. To the staples; Rosemary, Bay, Thyme and Mint can be added the more tender and annual members of the group; Sage, Parsley, Dill, Coriander. Read and research in the warmth of your home and be ready to sow and plant with lengthening days.
Best wishes for the New Year and successful cultivation through 2010.
As observed during December 2008
Fallen frosted angels
An alternative title for today's entry could be 'time waits for no man'. My selection of seasonal plants of interest for these pages is rarely influenced by the whims of others in the Garden, however many drew my attention to the merits of today's choice. Just a pity I did not act sooner!
Unfortunately the St Andrews weekend also brought freezing air temperatures - four consecutive days of minus 6 to minus 8º C. Combined with an average of four hours of sunshine each day, these weather conditions have caused the blooms to discolour and drop. With the rapid thaw causing the sap in the cells to rupture, the colour washes out and in parts the petals become translucent. Oddly, they also take on the smell of cold stewed tea.
This specimen of Gordonia was collected in Vietnam on a north-east ridge at 2340m above the village of Sin Chay. To verify it to species level in the herbarium a seed pod is needed.
The good news is that there are a multitude of terminal flower buds ready to open. The flowers have pure white petals 120 - 150mm across with a mass of stamens loaded with pollen in the centre.
The evergreen leaves are glossy above with the upper length of the edges shallowly serrated and showing red in colour.
Sprouting and flowering
The mahonias are flowering - the shiny evergreen foliage is offset by terminal panicles of yellow flowers. Mahonia napaulensis grows within Quercus and Rhododendron forest at 2,780metres. Our specimen in the Herbarium car park was collected in Nepal on a ridge north of Kumatoang, and has sprouted late extension growth. The leaves are just turning green from the juvenile bronze. When mature, there is a vague blue tint to the foliage.
Following the recent frosty spell, the tips of these leaflets have turned black. Survival to maturity may be doubtful.
Several racemes extend from the terminal bud, individual flowers are a bright yellow, most welcome in this season of low daylight hours. The delicate scent from these flowers is an added bonus.
An exotic fruit
On a west-facing wall, the evergreen climber Holboellia grandiflora is fruiting. The intertwining mass of tangled growth shelters the lurid purple fruit which is unfortunate, as this is a definite show-stopper.
The generally cylindrical-shaped fruit hangs from a long stalk emanating at a leaf axil and developes to 130mm in length. The inner contents of cloudy white, gelatinous bulk hold the shiny black seeds.
The leaves are set in fours or fives and readily clothe a wall. The leaves are mid-green above with a pitted grey appearance below. This vigorous climber reaches 5 metres here in the Garden; with support is has the potential to reach double this height. In the wild, Holboellia grandiflora is found scrambling over shrubs in stream valleys in south-west China at around 2,800 metres.
Fresh green flowers
Helleborus foetidus is an evergreen perennial ideally suited to semi shade and a deep moist soil where it will clump and colonise to flower impressively annually.
Although the flowers are not fully open it is the freshness that attracts the eye. Much needed on the cusp of lengthening days. The dominant flower part is the flat leaf like bract which is protecting the unopened bud.
The foliage when bruised emits a pungent smell which gives the plant its name. Deeply divided the finger like leaves are a dark background to the flowers.
Native to western and southern Europe. The seed of these plants were collected in the principality of Andorra at 2300 metres altitude
Review of the year
2008 was a year of desperate weather conditions. The wettest August was recorded with correspondingly low sunshine levels. Indeed on the 6th of the month the rain gauge almost overflowed with 63.6mm of rain in 24 hours. Let me remind you of the short dry spells of early June and mid July both yielding a week of temperatures in the 20's ºC and would you believe, dry. Now the coldest start to winter for 30 years and throughout the year working with soil that rarely dried out. In some areas the lawns have a pontoon feel when walked across. In consequence these areas have been difficult to mow. The first cut was on 28th January and interesting to note Daisy's (Bellis perennis) were flowering in December. The weight of the machines on waterlogged soil is a fatal combination causing damage to soil structure so mowing did not continue far into the autumn.
With the increasing heavy rain it is noticeable how bare soil becomes degraded. Droplets create a capping effect on the soil surface which then leads to erosion. In the vegetable garden and through bare borders a green leaf crop sown will help stabilise soil until cropping or replanting commences in spring.
Need a job for the winter months? plant shelterbelts and hedges for future generations to appreciate. If not able to undertake a project of this size decide on a tree suitable for your garden and plant it. Don't procrastinate for another year.
Leaving the year with seed heads, the attached image of swirls of fluff resembling cotton wool adorn Clematis 'Bill Mackenzie' on the wall at the Alpine house area. (For description see archived seasonal plants of 5/10/2007.) The long filaments that make up this head of seeds are the styles, gently curving and covered in minute silvery hairs.
Best wishes for the New Year and may your plantings prosper throughout 2009.
As observed during December 2007
A woody member of the family Violaceae, Melicytus angustifolius has beautifully coloured berries. Partially white and partially grey, they have the appearance of the Chinese Yin and Yang symbol. To add to the illusion when picked a black eye is evident at the abscission point. Squeezing will produce a purple juice that stains the skin and release the singular black seed. This plant has grey stems on which the berries are closely held, the leaves also tightly held to the stem are mid green in colour and sparsely produced giving a depleted appearance at the shoot tips.
Heading from the Chilean area where M. angustifolia is planted, also from New Zealand is M. crassifolius growing at the south east corner of the Temperate Palm House. Much leafier than M. angustifolius, the leaves are a glossy dark green with a more rounded shape. It holds a generous crop of berries which are in the main white with a little grey coloration.
For those inspired by the genus, mention should be made of M. alpinus and its cultivar 'Pygmaea' both growing on the New Zealand bed in the Rock Garden. Neither carry berries and would not be attractive to anyone but the most devoted plantsman, both with a prickly topping of defoliated spines, of which 'Pygmaea' has the softer spines.
Look at the seed of Euptelia polyandra, the distinctive hook in the samara gives it the appearance of a bottle opener. A native to Japan, growing in the upper Woodland Garden to the west of the Rock Garden. Here the seed is not as profusely produced as in the wild where it grows as a pioneer plant. One seed is held in each papery coat, known as a samara. Distinctly green where it is held, the samara is shaped to allow the wind to catch and disperse the seed as it ripens and falls.
Individual leaves are as wide as long (150mm x 150mm) with a pronounced tip and serrated edges. These produce reddish brown autumn shades but our specimen does not stand out as a tree with notable autumn colour.
The trunk and older branch network are pitted with a multitude of horizontal rust like lesions adding character to this vigorous young tree.
Awarded a preliminary commendation from the Royal Horticultural Society in 1957, followed by an Award of Garden Merit and a First Class Certificate, Mahonia x media 'Charity' is an evergreen flowering shrub that provides colour to the garden in the lead-up to Christmas. The leaves can be composed of up to 19 glossy green, spiny leaflets depending on the health of the plant.
It is a vigorous hybrid between the pollen parent M. japonica, from which it inherited the very faint fragrance and the length of the individual racemes, and the seed parent M. lomariifolia, from which it inherited its stature. The upright setting of the flower stalks within the raceme is also present in this parent.
This shrub adds interest to shaded areas, or in spots where a shaft of winter sun will catch these yellow flowers for greatest effect. With age it becomes a leggy specimen, easily reaching four meters. This is soon remedied with a pair of loppers in late March just before growth starts. New growth is produced from pruned shoots which will flower at the seasons end.
M. japonica is a smaller growing, less vigorous specimen. The racemes have a flattened formation, long and gracefully held. The globular buds are a glaucous green, attached by a short stalk, and open to a light yellow colour and with a hint of fragrance.
M. lomariifolia also reaches four meters in height and has long leaves composed of up to 37 leaflets. The flowers are a buttercup yellow and although Bean, in his book Trees and Shrubs Hardy in the British Isles, states they have scent, I could not detect any.
Take a walk on a winter's day to appreciate all three growing in the Garden:
- M.x media 'Charity' in the Demonstration Garden.
- M. japonica to the south of the Queen Mother Memorial Garden, with another specimen of 'Charity' growing nearby.
- M. lomariifolia in the cultivated area to the north of Inverleith House, very shy to flower and almost over.
A plant of seasonal interest, Ilex aquifolium has a wide geographical distribution ranging through South West Europe, North Africa, to South West Asia. Cultivated in Britain for centuries.
Long associated with mystic power, sprigs of Holly have been used in wreaths since Roman times. These beliefs were adopted by Christianity and Holly is now firmly associated with Christmas. As Ilex aquifolium is dioecious, that is male and female flowers produced on separate plants, one point to remember when bringing holly into the house as decoration is that equal amounts of berried and non berried, (male), sprigs should be used. If not, this will determine the dominant sex of the household.
Through exploring and explaining the world of plants, we grow and conserve plants and appreciate their form in a garden setting. At the garden are huge stands of Ilex, containing a mixture of both male and female plants leading to good pollination and in most years a decent crop of berries.
Botanically these are referred to as drupes containing nutlets. Similar to a plum, a drupe is a fleshy fruit containing seeds, each seed surrounded by a hard, stony layer.
The glossy evergreen leaves vary in their shape, shade and prickliness, some devoid of teeth and totally smooth in outline. Once established these strong growing plants make first class hedges and where room allows solid windbreaks.
Two yellow variegated cultivars of note are 'Golden Queen', a male flowered c.v. growing as a mature specimen north of the copse. The leaves are edged with sharp teeth whereas 'Golden King', has mainly smooth leaves. It is conversely a female flowered and berrying c.v. Seen growing as a young specimen in the Queen Mother Memorial Garden.
Mistletoe, (Viscum album), has a place in British social history. The custom of kissing beneath the Mistletoe dates from a long forgotten fertility rite, possibly linked to the Druids who especially prized Mistletoe that was hosted on Oak trees. As Viscum album remains green throughout the year it was thought to maintain the life of deciduous trees through the winter months. The most common host is the orchard apple with Tilia and Crataegus also popular.
During the 1890's a local botanist, William Paxton introduced Mistletoe to several locations in Edinburgh, notably the Dean Cemetery. Naturally spread by birds, the Mistle Thrush is the primary vector spreading the seed by defecating partially digested seed and the viscous jelly on host branches. Other birds spread the seed by beak wiping on host branches. The attached image of the white berry shows the strands of viscous gunge that conceals the individual seed. This stringing allows the seed to stick to a host branch. Germinating in spring a hooked hypocotyle locks into the bark surface. Gradually penetrating to the cambium layer it becomes parasitic linking into the xylem of the vascular system to obtain water and soluble nutrients. Through photosynthesis it converts sunlight into growth energy. It is thus not a true parasite but a hemiparasite.
Much of the Mistletoe sold in Britain originates from France where it is prolific.
In November and December an annual Mistletoe auction takes place in Tenbury Wells, Worcestershire. Extracts from the plant are used in medicine and herbal remedies.
The inconspicuous flowers open during the winter and are pollinated by insects. The plant in the garden is growing on Aesculus flava and was introduced as seed from East Lothian in 2000. Viscum album is a dioecious plant and the one we grow is male.
Looking at the attached image the sturdiest parent stalk can be seen at the top of the Aesculus branch. There are two other stalks, one slightly less vigorous and another barely visible as a peg. Once established the mother plant sends these shoots up from subterranean haustorial strands and so the colony develops. Trees hosting colonies of Viscum album may show a loss of vigour and yield but rarely will an infestation kill the tree.
Grass cutting commenced on 1st February after a very mild, wet winter. Irrigation was much needed for the Rhododendron collection as growth flushed in the spring and flowering commenced.
The sunshine and warmth at Easter, the cool wet summer and the extended dry autumn provided the climate for plant growth in 2007. Autumn colour was average but what did surpass all expectations was the extended flowering of many South African natives cultivated in the Garden.
This month has illustrated how changeable our weather patterns have become, two days of frost, a mild twenty four hours and then a return to freezing temperatures. Ideally this spell needed continuous freezing temperatures to reduce the population build up of pests and diseases, some of which were previously only found in the banana belt or under glass.
Favourite plant of the year? For me a close call between the aristocratic Agapanthus caulescens and Lapageria rosea, which incidentally is continuing to bloom.
A first flowering from a collecting trip to Iran in 2005 has been identified as Iris pseudocaucasica. Collected by the intrepid trio Mitchell, Rae and Miller on the journey between Tabriz and Jolfa at 1462 metres. It can be seen in the alpine house. The petals are lemon yellow with longitudinal black striations. There is a pronounced deeper yellow marking on the fall of the outer petals. Arched leaves with a distinct silver edge and silvery sheen grow out from the brown remnants of the sheathing leaves held at the base.
Finally, be aware that if the soil sticks in clumps to the soles of your boots as you work it: Don't; you will ruin the structure and impede drainage. Take the time instead to visit the Garden here or one of our regional gardens; Dawyck from 1st February, Benmore and Logan from 1st March for ideas and inspiration.
The attached image shows the sun setting over the garden on 2007. A Happy New Year and successful cultivating and growing throughout 2008.