As observed during June 2008
2/6/2008
Strawberry fields forever
A visit to the Demonstration Garden will reveal a mass of strawberry flowers. Fragaria 'Pink Panda' is a carpet of pink bloom. This vigorous herbaceous member of Rosaceae covers ground through stolon production. A simple and effective means of vegetative propagation, these overground runners radiate away from the mother plant, rooting to stabilise at a node then continuing to arch over the soil, forming second and third plantlets. Decorative rather than productive, few fruits result from this prolific flowering.
Heading further west to the areas of calcareous grassland reveals Fragaria vesca, the wild strawberry, a native of the temperate northern hemisphere. These plants were growing and seeding one mile north of Loch Achall near Ullapool in the vicinity of a limestone quarry overlying granite rock, on a north-facing slope of grazed grassland among rock outcrops growing with Thymus, Alchemilla, Sedum, Blechnum and Gramineae. The plants were brought to the Garden in 1997 when the area of quarry was extended, leading to destruction of habitat.
This white-petalled species of wild strawberry was the basis of strawberry production in Europe. Cultivated since the 1300s, initially in France, production was prolific at the gardens of the Louvre in Paris. When travel and exploration extended the boundaries of knowledge, larger fruited species from North America were collected and shipped to Europe. Thus the soft fruit industry bred and refined selected forms for fruit production.
6/6/2008
A Monocarpic Campanula
Campanula thyrsoides is a monocarpic species that is well worth cultivating for the flower dome that is clothed in individual creamy white flowers. From a distance the spike looks yellow. Within the individual flowers are thin anthers in the cupped base. The stigma pushes the green styles out of the fused petals which are pointed with six tips.
Sow seed annually to keep a succession of plants growing as this has a biennial life cycle. In year one the vegetative work is undertaken. A rosette of foliage develops to bear the flower spike which appears in the second growing season extending to 350mm and c.200mm in diameter to resemble a retro light bulb and disseminating a delicate scent.
The leaves are mid green, covered in hairs, long pointed shape and nestle close to the ground during the first year as growth commences in the second year with the development of the flower spike leaves are taken up from the ground hugging rosette and appear to twist and curl at the ends.
Native to the Alps of Central and Southern Europe it can be seen at the very east end of the alpine wall growing in a free draining root zone.
10/6/2008
The lantern tree: lighting the way towards midsummer
A young plant in the south area of the Rock Garden is the Chilean lantern tree, Crinodendron hookerianum, so called by the shape and orientation of the flowers.
This evergreen reaches 3.5m in the Valdivian rainforest of southern Chile, where they are seen growing on riverbanks from sea level to 600m. Fruit production is abundant in the native populations.
Here at the Garden, flower bud production commences in autumn but it is now that the pink shades of the lantern-shaped corolla are fully appreciated. The fused petals that make up the corolla are waxy thick; on fading, they disintegrate apart revealing the decorative flower parts. When complete, the top is a serrated circle which would double as a pastry cutter. Take a moment to appreciate the artistic twist of the anthers and filaments. At the base of these are the buttercup-yellow nectaries.
The flowers are held on stalks from the leaf axil on the previous year's growth. As the wood ages the brown stems are covered in white lenticels.
17/6/2008
An unaccessed hidden gem
A botanic garden holds a unique collection of plants. These are given individual accession numbers of eight digits: the first four refer to the year of introduction the second four are sequential for the number of introductions in that year. Individual numbers recording data from plant collecting trips across the globe, donation information, images and verification notes. There are occasions where a self-sown seedling springs up and merits attention but not accession.
Tucked away to grow in peace behind metal barriers at the access gate on the west boundary is an interesting biennial, Silybum marianum. This, the best specimen I have seen growing in the Garden, is a reclusive escape from previous introductions to the Garden.
The species is native to the warmer climes of the Mediterranean, south-west Europe and into Afghanistan.
Silybum marianum is a composite milk thistle that produces and sets multitudes of viable seed after the large, purple flower heads fade. These are protected, like the leaf edges, with sharp spines, defying any predator to use this plant as fodder.
The real beauty is in the marbling on the leaf. White and silver streaks and flecks coalesce and contrast with the mid green pigments that bind the foliage together.
This truly magnificent specimen spreads and towers to 1.6m. It's just disappointing to realise that it will die back and compost into the ground as flowering and seed production guarantee the next generation.
20/6/2008
Native Yellow Flag Iris
Planted in groups through the garden and a common sight in less well drained locations around the country is one of our native Iris, Iris pseudacorus. Collections have been made from populations near Arisaig on the west coast of Scotland and on the edge of Loch Lubnaig in the Trossachs. Also found through Europe, North Africa and S.W.Asia this is a vigorous rhizomatous spreading monocot, loving moisture retentive soil in full sun.
The sword shaped foliage has a beautiful sheen that holds rain water droplets even on those leaves curling to a 60 degree slope from which rain would normally shed. A pronounced mid rib runs the length of the leaf, distinctly felt when running the leaf between finger and thumb.
Leaf growth rises to two metres sitting proud of the flower spikes. These spikes produce five or six blooms with outstanding vivid yellow flowers. The buds unfurl from a perfectly pointed pencil shape into three large yellow petals. The centre of each has a darker yellow blotch radiating from which are vein markings in brown. Loved by bees which delve between the lower petals known as falls and the upper (standard) petals in their hunt for the nectar pools hidden at the base. Often overlooked are the stigma and style, which resemble petals, standing prominent in the centre of the flower. The stamen is tucked beneath the fallen, lower petals.
24/6/2008
A giant lily with stature and scent
Cardiocrinum giganteum is one of the prizes of the Himalayan flora. Collections in the Garden have come from the provinces of Yunnan and Sichuan in south-west China. In the wild, it grows at 2400-2600m in degraded open forest with Abies and Larix sp. in Yunnan and within damp glades in mixed woodland with Acer sp. and Rhododendron rubiginosum in Sichuan Province. This giant lily is a gem to collect - its seed, tightly packed in the pods, burst out like coins from a cash machine.
To get the best out of these seed-grown plants, they are introduced into woodland areas at Edinburgh. Being monocarpic it is essential to sow seed each year bulking up plantings for successive flowering. Initially growth is a basal rosette of leaves these develop over five to seven years until the bulb reaches flowering size.
Leave the flowering stalks once flower colour and petals have dropped - these make bold statements during late autumn and winter when they dry naturally to a handsome brown shade.
Grouped in dappled shade, the plants are showing their variability in form; the tallest exceeding three meters in height in the Copse and the most densely packed heads in the Woodland Garden sporting in excess of two dozen individual blooms with stems thicker than a hand's grip. Flower colour varies from white to cream to a very delicate shade of green. Most are suffused with shades of vermillion in the throat of the bloom and on the outer of the petal less so.
Each and every one is laden with scent, all the more powerful and heavily intoxicating this rainy mid-summer.
27/6/2008
Eyelashes to die for
Look into the carmine pink petals of Geranium psilostemon: the black lines spaced evenly and radiating out from the base to the tip of the petal resemble a geisha girl's perfectly manicured eye lashes. Our specimen was collected in Turkey near Trabzon on the Black Sea coast at an altitude of around 1,450m.
This herbaceous geranium is a vigorous clump former, reaching 1.6m and still able to withstand a battering from wind and rain without additional support. Though it enjoys a warm climate, it nevertheless colonises and grows to good effect here.
The distance between nodes can be 600mm; swollen basal nodes split and shoot away. The leaves are soft to the touch, deeply divided and held on long petioles. The flower buds nod downwards in anticipation of opening. The petals are cupped initially and reflex with age. On dropping, the spider-like floral parts remain encased by five green sepals with prominent tips.