Garden highlights in March

As observed during March 2013

26/3/2013

Sandmat

Clumping over a mound in the rock garden is a sturdy plant; Arctostaphylos pumila, an evergreen shrub of the Ericaceous family.Arctostaphylos pumila

It is endemic to a small area near Monterey on the Californian coastline, in North America, where it can be found beneath Pine trees and on the coastal strand. The leaves are shrouded in fine downyArctostaphylos pumila hairs giving a degree of protection from desiccation by coastal breezes. This is especially noticeable on the newly emerging growth and gives a surprisingly soft feel to a ‘lino’ like leaf. Beneath theArctostaphylos pumila foliage is attractive reddish brown bark, which flaks with age.

This plant is on the verge of flowering, the cluster of immature ivory bells hang down from terminal growth.

19/3/2013

The difference a week of weather can make.

Last week saw driving snow storms, freezing temperatures overnight and bright sun leading to a rapid thaw early on in the day.Cornus mas
Some plants thrived; it was the demise of an annual show of flowers in others.Cornus mas ’Macrocarpa’
Large deciduous specimens of Cornus mas are unscathed; the flowers slight scent should be appreciated as these remain in profusion on the plant.Rhododendron aff. faucium
Rhododendrons on the other hand fared poorly. The attached image shows the ring of petals despatched from Rhododendron aff. faucium. Still colourful but will bleach and rot rapidly.
We are unlikely to get the warmth and sunshine hours of last March so when thinking of replanting containers with seasonal material be circumspect in your choice. More snow on the way!

12/3/2013

Viburnum furcatum Viburnum furcatum
This plant is worth a closer look as the buds expand and the embryo foliage emerges from tight buds. Specimens of Viburnum furcatum are planted near the upper woodland garden. The fresh young leaves are covered in brown felt and exhibit distinct structural venation; as worthy as any scented blossom in attracting passing attention. The older wood,Viburnum furcatum pock marked with lenticels, the young shoot covered in white down. It was collected as seed from a two metre high deciduous plant near, Amori Prefecture, Honshu in Japan.Viburnum furcatum There it was growing as understory in Fagus crenata woodland with Sasa kurilensis at 880m.

4/3/2013

Allionii at alpine level

Flowering in the alpine house at the Garden is a collection of Primula allionii. Primula allionii collection
One specimen collected, as seed; from limestone cliffs in the French Maritime Alps is a cushion of magenta pink colour. The edges of the petals neatly subdivided. At an altitude of 700 – 1900m these stunted looking clumps of vegetation cling to the rock face. Making use of cracks and crevices to gain a root hold. Primula allionii
The lighter coloured image shows the cultivar Primula allionii ‘Anna Griffith’, one of the most popular cultivated varieties. Exhibiting a delicate pink shade with distinctly frilled edge to the petalsPrimula allionii ‘Anna Griffith’.
 
In the alpine house these are potted into an open mix, grown in clay pans and then plunged into a sand bed ensuring the root zone is kept cool. When watering due care is needed to prevent any landing on the foliage. The best plants thrive when spent flowers are removed along with any aged leaves.

 

 

As observed during March 2012

27/3/2012

Leafing through Lupins

We are now observing good growth on the emerging herbaceous plants. Taking a closer look at the emerging foliage on some reveals colonies of bugs and beasties. This image of a Lupin cultivar shows an active colony of Lupin and Macrosiphum albifronsLupin Aphid, Macrosiphum albifrons.
Not easy to control culturally or organically, repeat spraying with dilute dish washing  water may reduce the population but never totally wipes it out.  Lupin and Macrosiphum albifrons
These aphids overwinter within the shelter of the dead basal foliage, grasping the chance to feed on the fresh sap. These are wingless adults, winged adults appear during the summer when the colony is too large to support itself and these fly away on the breeze to colonise other Lupin plants.
 

19/3/2012

Invasive alien

Libertia sessiliflora, collected in Chile and obvioLibertia sessiliflorausly enjoying our climate. The soil surface beneath the colony of mature plants is awash with germinated seedlings from the parent plants. This plant has the potential to become an invasive alien, the prolific seed production and germination rate as seen in the attached images have the ability to procreate exponentially. 
The Scottish Government has set up a working group to promote the conservation of biodiversity within our native flora and fauna. Legislation will be enacted to strengthen the case for control of alien species that pose a threat to our native flora.
At present this is governed by The Wildlife and Countryside Act 1981; amended by the Wildlife and Natural Environment (Scotland) Act 2011. The “WANE” Bill makes it an offence to sell any invasive plant or animal on lists prepared by Scottish Ministers. 
Many non native species are now considered invasive and are appearing on lists which then prohibit their sale orLibertia sessiliflora planting in areas where they would pose a threat to native vegetation. This is often due to their thug like characteristics; think of the swathes of Rhododendron ponticum that cover hillsides and estates. Plants that invade water courses are a particular area of concern; Hydrocotyle ranunculoides is a non native invasive species which is a problem in this type of habitat.
Keeping things in perspective; our garden flora would be the poorer without the diverse range of plants collected worldwide, thriving in the temperate maritime climate and now populating our gardens with an array of colour, form and function
 

5/3/2012

Floral scents

Abeliophyllum distichum Abeliophyllum distichum exuding floral scent from the mass of pink tinged blossom covering the deciduous wood. Worth a walk to the south facing border at the foot of the Arid land house to appreciate.
Plant this slow growing shrub in full sun to allow the wood to ripen in the summer, anywhere else this far north and the plant will sit and sulk.Abeliophyllum distichum
 
Introduced from Korea in 1924 where the summers bake the wood allowing reliable flowering.  Sharing the family Oleaceae and the characteristic pithy, hollow stems with another spring flowering favourite; the genus Forsythia.
 
 
For previous years' highlights during this month, see the March Garden Highlights Archive page.

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