The October Garden
This year the Castle and Gardens has been opening half an hour earlier each day. Also, due to the popularity of our tours and events, we have extended our 2015 season by a whole month – so the Castle and Gardens will be open until 31 October!
Perhaps surprisingly, but much due to the mild climate we have here in Pembrokeshire, there is still a huge amount of colour in the Gardens during October and everything looks great. Last year the Jungle Garden (which is one of the largest in the UK) was still magnificent and luxuriant and the ornamental grasses in the Walled Garden looked stunning so take advantage of this and do come and enjoy our wonderful garden for all seasons!
Roddy Milne, our Head Gardener, loves to share his passion for plants. Each week throughout the month we will add one of his favourites….
The Maidenhair Tree – Ginkgo Biloba
You do not often associate conifers with spectacular autumn colours, however there is one species that turns an intense bright yellow every year. It is Ginkgo biloba, commonly called the Maidenhair Tree. The leaves are a unique shape among plants, being a fan shape that resembles those of the dainty native maidenhair fern.
There is fossil evidence indicating that Ginkgo trees have been around for 270 million years (some authorities think 350 million) and that they once had a very wide global distribution. Now they are only found growing wild in two small areas of eastern China and even here it is suspected that monks were influential in maintaining these populations, through monastic gardens, for the last thousand years. Throughout its long history Ginkgo has remained virtually unchanged and today they represent the only living bridge between ‘higher’ and ‘lower’ plants (between ferns and conifers). Maidenhair trees can be extremely long-lived, the oldest recorded individual being 3,500 years old. They are now very widely cultivated, the first being planted in Britain around 1760.
When young, Ginkgo usually form tall slender trees and as they age they develop wide spreading crowns similar in shape to a typical deciduous tree and unlike any other conifer. They can grow up 30m tall however there are a number of dwarf varieties available that are easier to accommodate in normal sized gardens. They are easy to grow in good fertile soil and are happy in the shade of other trees.
Ginkgo biloba has been used in Chinese traditional medicine for centuries and today, it is also cultivated for use in Western medicine. The leaves are used in herbal remedies for cognitive complaints, such as Alzheimer’s disease, dementia and vertigo. It is possibly Europe’s number one selling herbal medication being used to improve blood circulation but it is also used for many other conditions, including ADHD, depression and other psychological conditions.
The pure yellow of Ginkgos autumn colour makes it a memorable autumn sight and it is a worthy plant to grow on account of its long and fascinating history.
Some plants, like some people, make an instant and lasting impression. For me and many other gardening folk Selinum wallichianum (sometimes known as ‘Wallich milk parsley) is such a plant. It has a wonderful combination of a strong structure composed of refined and delicate parts.
In spring, a mound of highly dissected, feathery, pale-green foliage emerges, from which rise, during the summer, strong stems up to a metre tall that are topped with highly intricate, flattened umbels composed of tiny white flowers. Within the flower- head the individual flowers are held in little round groups which creates an interesting pattern when viewed from above. It looks like a robust, more substantial, cow-parsley. After the summer flowering is over the plant will produce an abundant second flush of flowers that last well into the autumn.
Selinum wallichianum has been grown in gardens for well over a century since its introduction from the Himalayas where it grows in scrub and mountain meadows. It relishes growing in good, deep soil in a sunny or partially shaded location but will tolerate less luxurious conditions. It is deep rooted and once planted will not appreciate being moved or divided. We have found it to be very long lived – our original plant is now fifteen years old and still going strong. It can easily be raised from seed and new plants will occasionally pop up next to the original plant. When
choosing a spot for it to grow, it is worth placing where the flowers and structure of the plant can be easily and closely inspected, although it will also be happy and look lovely growing in amongst other plants.
Sorbus ‘Joseph Rock’
The genus Sorbus, of which our native rowan or mountain ash is the best known member, are among my favourite trees. Strangely we have quite a few native species of Sorbus, most of which have a very limited distribution; one species only occurs in one glen on the isle of Arran in Scotland (Sorbus arranensis) while another is only found in the Avon Gorge (Sorbus bristoliensis).
Due to their wonderful show of berries, Sorbus come into their own at this time of year and most types are excellent garden trees as they are relatively small. There are a great number of species to choose from, mostly of Asian origin, and also a large number of cultivated varieties.
We have about half a dozen varieties growing here at Picton and we planted an additional fifteen, as yet tiny, new varieties last year. My favourite is Sorbus ‘Joseph Rock’ which has bright yellow berries and small leaves like an ash tree which at the moment are displaying their rich autumn colours. The berries tend to remain on the tree after leaf fall as birds tend to prefer red and orange fruits. It is a tree of upright growth and will usually grow to about seven metres tall and like all Sorbus is easy to grow liking moist but not waterlogged soil and a sunny location. . In the spring it will reward you with clusters of small white flowers.
The tree was named after Joseph Rock an Austrian born, (latterly American naturalised) botanist who travel widely in China. He was reported as being an eccentric character, always carrying with him a canvas bathtub and silver cutlery on his many arduous excursions across this country!
Red Abyssinian Banana
One of the most dramatic, perhaps even garish, plants that we grow here in the gardens of Picton Castle is a red leaved banana. Its scientific name is Ensete ventricosum ‘Maurelii’ but it is sometimes known as the ‘Ethiopian black banana’ or the ‘Red Abyssinian banana’. Ensete ventricosum is native to Ethiopia and Angola and the variety ‘Maurelii’ is a selected form of the species that was discovered growing wild in Ethiopia.
During the summer it produces enormous paddle-like leaves up to three metres long (much more in tropical places) that have a wonderful deep-red colouration. I am often asked by slightly concerned visitors what it is, and sometimes if it is real. It certainly has a slightly alien look about it. We grow it in our ‘Jungle Garden’ among lots of other large leafy green plants and in this location it manages to look quite at home. The leaves are slightly translucent and look fantastic with sunlight passing through them providing a whole new range of red shades of colour.
‘Maurelii’ grows very large and is not frost hardy and therefore presents an ever growing problem for the winter months. Before the first frost arrives most of the leaves must be cut off and the plant dug up and potted for the winter months. It must be kept frost free for the winter in a heated green house, poly-tunnel or conservatory. Our plant is three years old and about seven feet tall, next year it may be ten foot tall and becoming more problematic to find a large enough winter home.
When the spring arrives and the danger of frost is over it can be planted out again. During the summer months it is easy to grow and enjoys plenty of moisture and sunshine. It is best to be positioned in a sheltered place away from wind that will shred the large leaves, and a mulch of manure or compost round where it grows will ensure luxuriant growth. It grows quickly and new growth can be easily observed every week! Despite the work of bringing indoors each winter, the ‘Red Abyssinian banana’ is a plant that I enjoy so much during the summer that it earns it keep though its dramatic spectacle.
A Different Sort of Daisy
Michaelmas Daisies comprise various varieties of the genus Aster. They are wonderful late flowering herbaceous perennial plants that provide a bountiful display of daisy-like flowers during the autumn. Their flower colours beautifully compliment the kaleidoscope of autumn colours provided by trees and shrubs. In particular there is one ubiquitous old, mauve coloured variety, with slightly floppy flower stems, that has deservingly and unobtrusively found itself a home in most long established cottage style gardens.
Aster lateriflorus var. horizontalis (sometimes called Horizontal calico aster) is different in appearance from the others. It grows to about seventy centimetres and produces thousands of tiny white, pink tinged flowers on many branched stems. One of the interesting features is that all the side branches to the main stem are completely horizontal to the ground which gives the overall floral show a slightly tiered effect. With each of the thousands of flowers being only a centimetre across, the plant can look cloud-like when viewed from a distance. Unlike many varieties of Aster this one is entirely self supporting and will not require staking to prevent the stems from flopping over. Here at Picton it is very easy to grow, being slug proof, unfussy about soil type, long lived and a delight every year, even though few people venture out visiting gardens at this time of year.
Ornamental grasses can add a wonderful elegance and texture to a garden. Many taller varieties can also bring a sense of movement, even in the lightest breeze. With some sorts, the flowers are held well above the leaves and create the sense of a view of what lies beyond through the lightest veil of feathery flowers.
Miscanthus are sturdy, block-like plants with slightly weeping foliage and a strong vertical accent to the flowering stems. These stems grow through the summer months and then start flowering around August. The flower-heads and leaves provide a fantastic range of brown and yellow colours right through the autumn and winter as they slowly decay. The stems and leaves are completely herbaceous in that they re-grow from ground-level each year, a seasonality that I love.
There exists a wide range in cultivars from half to three metres tall, each with its own individual form. All are very easy to grow and are unpalatable to slugs. One of my favourite varieties is Miscanthus ‘Malepartus’ which grows to between 1.5m and 2m and has wonderful dusky-red flowers and nice gentle autumn colours. I avoid cutting it down until as late as possible (around March) to get the most from the plant.
Sedum ‘Autumn Joy’
Sedum ‘Autumn Joy’ is a plant as much admired by bees as it is by gardeners. Early in the year pale-green succulent stems emerge from the ground and continue to grow through the summer until the flowering time in September and October. During the summer the solid looking form of the new growth provides a strong focal or anchor point for a flower border. The flowers when they open are a massed head of dark-pink, in heads ten to fifteen centimetres across. These last for weeks before turning a beautiful russet-brown for the winter months. For me this is when it is at its best.
One slight drawback with this Sedum is that it is inclined to flop over just as it is about to come into flower. A large established clump can sometimes look as though a large dog has had a brief nap in the middle of the plant and left a nest-like shape. To combat this flopping some gardeners give the plant the ‘Chelsea Chop’ during May at the same time as the Chelsea Flower Show. This consists of trimming off the top ten centimetres of the stems causing them to branch out and reduce the final height at flowering time, thus preventing the flop. This year I plan to move most of our ‘Autumn Joy’ to a very exposed, sunny site with poor stony soil. Such extreme conditions should also stop the flop. There any many other Sedum varieties on offer from nurseries, many of which are very beautiful but few of them are as easy to grow and slug-proof as ‘Autumn Joy’.
Bananas in Pembrokeshire
If we have a nice long, hot summer some of the banana plants in our Jungle Garden come into flower. The bees get busy feeding on this strange looking flower and with any luck we have a crop of inedible micro-bananas before Christmas – but even so, it still feels like quite an achievement!
The hardy Japanese Banana, Musa basjoo, is the only sort that can be reliably grown outdoors year-round in British gardens. In a very cold winter the entire plant can be killed back to ground level and will re-emerge from suckers beneath the soil, however with a mild winter like the one a year ago, the plant can stay evergreen and grow to massive proportions during the summer months. The Picton plants have grown to over four metres and the individual leaf blades are half a metre wide and two metres long, providing a wonderful tropical look.
In the winter it is advisable to protect the basal parts of the plants to ward off the worst of the cold. This can be done by wrapping the base of the stems in a layer of straw held in place with string. Alternatively, a temporary fence of netting or fleece can be constructed round the plant and the enclosed space filled with straw or autumn leaves. Musa basjoo is easy to grow and unfussy about soil type but they perform best in full sun and sheltered from strong winds that can turn the leaves to ribbons.