Bretschneidera sinensis

I’m afraid that I havent had much time or energy to post much recently. Now that we have had at least a rain splash and temperatures have dropped back to normal the garden is looking slightly more refreshed. There is one tree that has looked magnificent right through July and August though and it is pictured here before any recent rain. The large leaves up to a couple of feet long haven’t looked like drooping or browning off to any extent at all. The late Peter Wharton did say that the trees he had growing in the UBC garden in Vancouver were always strong in an extended dry spell, and this has proved to be the case here as well.

Bretschneidera is a Monotypic Tertiary relict tree and rarely encountered even though its range extends from Thailand/Vietnam into China and Taiwan. Having emerged early on in the evolutionary chain and withstanding extremes of climate and glacial periods over many Millennia may explain how it has brushed off this recent testing dry spell in Cornwall as a mere blip. As a cultural tip the root system has strong mycorrhizal associations within undisturbed warm temperate forests. So if anyone is lucky enough to receive a plant in a pot then its best to get it into a piece of ground fast where there is a deep mixed leaf layer amongst other trees. Thereby freeing it up from sterile mediums which humans have been interfering with and where it will die in a flash. This tree is about 25 years old now, but hasn’t shown any urge to flower yet as no doubt it is in for the long haul which is a shame (for me anyway) as the flowers are spectacular white/pink erect spikes as seen recently by some botanist friends in Nth Vietnam.

Christmas Day

For generations it has always been the tradition at Gwavas in New Zealand to pick Rhododendron dalhousiae var rhabdotum to display on the table for Christmas Day. So here it is on the 25th of June in Cornwall flowering exactly six months away from our next Christmas. I haven’t doctored these images with a felt tipped pen or highlighted the green in the flowers. The colour range is a stunning sight with buds opening green, passing through a yellow tint and when nearly over the scented trumpet shaped corollas are pure white. It is an exceptional late flowering Maddenia which loves this position in an old rotten tree stump as can be seen in the lower image. It is often seen as a straggly hanging plant growing epiphytically on cliffs and trees, so is well designed for a dry season which it has to withstand during the winter in its natural habitat.

This particular plant was collected as seed many years ago from the Eastern Himalaya by Steve Hootman and Ken Cox. It is a particularly fine form with up to five flowers in the truss. Very difficult to tell apart from the straight species dalhousiae when the flowers aren’t present, but this variety is generally seen growing further east in the Himalaya Range and blooms a month or so later with these unique flowers which always attract much comment from garden visitors,

Summer Solstice

This last week has been perfect for the colours in the walled garden. Many plants in this area are at their peak now and for the next couple of weeks. The main avenue of Cornus capitata and the rose borders are looking fine. The still conditions have meant their flowering period has lasted longer than some years. Other climbers around the walls such as Abelias, Lonicera calcarata, Actinidia spp., Trachelopsermums, Hydrangeas both shrubby varieties and the climbers, are looking great. Jo’s borders along the south facing terrace are near their peak and full of colour and interest. The contrasting foliage colours are fresh after the rain in early June and their is plenty to see in the greenhouses. The garden is open throughout the summer on Wednesday afternoons, tea and biscuits, AND ice creams are available in the entrance.

Sargentodoxa cuneata

There are a couple of old Captain Rawes camellia bushes in the NW corner of the walled garden that needed pruning this week. They were leaning away from the wall and in danger of toppling over. When I climbed the step ladder to get on with this job there in front of me was a lovely bright green scented flower from the Sargentodoxa climber which I hadn’t noticed from the ground. It was half hidden in the camellia foliage but now it is clear of the bush and on display properly, looking stunning. The leaves are showy and unusual as well, as shown in the lower image emerging a dusky red/brown colour and comprising of three leaflets on a common stalk.

It cant be seen all that often in cultivation as it doesn’t appear in the Hillier Manual but does rate a mention in Bean. This entry is mostly interesting for the fact that it first flowered in the UK in Horsham, May 1922, exactly 100 years ago to the month. Hopefully it will still be in flower when the Tregrehan Rare Plant Fair is on this Sunday. Entry is free to the fair and half price to the garden, see you there….

Huodendron biaristatum

No matter the season this tree always requires some sort of tactile attention when passing in a sheltered part of the woodland. This plant receives much more physical interaction than any other I can think of. It requires at least a good pat if not more, due to the trunk texture resembling parts of the human, particularly a leg or arm once the papery bark has peeled away. It seems as if with age there are many more wrinkles, much like ourselves as well….

The Huodendron are an outstanding group of 3 spp. all of which are growing in the garden. The flowers are small for a member of the styrax family but when given enough light the massed effect of the hanging clusters is showy when viewed from a few yards away. This display combines well with the lovely dusky pink young foliage and with the smooth multicoloured bark, its chief attraction. Relatively rare in cultivation I think mainly due to the tiny seeds, (about 1mm across) which are impossible to locate on the forest floor and difficult to sort out from chaff on the tree. It could also be its tender nature although the trees at Tregrehan haven’t been damaged with frosts to -6 degrees, but I would still recommend growing on inside till a metre or so before planting. Young plants are slow to build up strength and seem to have a weak root system which allows stem rocking until a reasonable age is reached.

Freycinetia banksii

I have been keeping a plant of this NZ member of the Pandanus family in the greenhouse as a mother plant. It really prefers to perch up on trees where it can send down long roots to the forest floor. The lower image below shows the incredible aerial rooting system of plants growing on large Dacrycarpus in coastal NZ forest. Large tangled lumps along with Collospermum crash down with branches occasionally (the early NZ timber fellers called them widow makers) creating chaos on the floor. The fibres were useful for the Maori people as tying cord and they used other parts of the plant for weaving and the fruit pulp is sweet and edible.

This fellow seems to be more than happy in the ground though where I can break pieces off, get them rooted and then try them outside epiphytically on host plants in the NZ part of the garden. It is always a pleasant bright green to look at it and surprised us by flowering this week for the 1st time. Reading up on the fertilization of the flower it seems that it may have been designed to be pollinated by bats. No rodents lurking in the NZ forest back along.

Rhododendron spp. petelotii and suoilenhense

Both of these rhododendrons have recently been introduced into the garden and flowered within the last 30 years. It seemed a good idea to plant them together as they often grow side by side in the high altitude regions of Nth Vietnam, where unfortunately their natural habitat range has become severely eroded.

Rh. petelotii is part of the Irrorata Sect. but doesnt flower as early as a number of others in the group thereby missing the worst of the spring frosts. It has one of the finest trusses with dark red flowers of any rhodo when fully open, and the colour here taken by digi camera doesn’t really do it justice.

Rh. suoilenhense is one of the larger growing species where it has already reached 6m in a sheltered spot, and is definitely happy as it is already self seeding around on old rotting logs. The immature leaves have a characteristic band of light indumentum which created some confusion with the similar leaved Rh. protistum when it was first seen. But once mature the leaf underside shows an attractive smooth light fawn colour.

Neither has suffered from any cold spells and are 1st rate plants that I can recommend for any large garden on acid based soils.

Hydrangea peruviana x serratifolia

This climbing Hydrangea is still wowing people with its flower show several months after first starting back in mid winter. Most of these Hydrangea lianas are white and have large sterile parts to their display so this plant attracts quite a lot of interest as can be seen in detail from the left hand image. It was planted at the base of a large Abies conifer about 25 years ago and apart from the occasional setback from a cold winter (-5 and below) it has thrived and has now reached about 20 metres by way of an aerial rooting system. Other plants in their native habitat have been measured at up to 60m, so this chap is just getting going!

The hybrid is derived from within the Cornidia section of Hydrangea which includes other more well known species such as H. seemanii and H. integrifolia. All originate from the New World apart from the latter in SE Asia. Freakingly this severance has been explained by long distance seed dispersal, it’s a long way to fly for sure. Excitingly there are several species planted on nearby trees which were collected by Bleddyn and Sue Wyn Jones, (with permits), in Central America. They have all survived a couple of mild winters so watch this space for more action on bare conifer stems in the Gondwanaland part of the garden.

Little Gems

There is suddenly so much wild colour about the garden all competing for the attention of the visitor. The various evergreen Illicium spp. with their scented foliage and quiet charm are 1st class shrubs and small trees but often overlooked in this visual overload. The vivid red flowered plant is Illicium mexicanum which has so far proved to be hardy here belying its origins, as have the two pale flowered Asian ones below. The white flowered image is Illicium macranthum and the yellowish flower comes from Illicium simonsii.

Both of the latter two also have strong scent, detectable from a distance even on a cold winters day often before the plant is noticed. The early season in the woodland wouldn’t be the same without these wonderful additions and it is definitely worth repeat planting them in many positions so as not to miss them on a casual wander. The edible spice star anise species is Illicium verum which is also growing in the garden but care must be taken with some of the species as not all their fruits are edible.

Atherosperma moschatum

This evergreen small tree is growing away nicely in the Gondwanaland part of the garden. In fact there are a couple of upright dense trees in this area. Both with attractive leaves which shine silver when the wind picks them up showing their undersides. In coldest February the dinky wee flowers never fail and cover the plant although one has to get up close to admire this aspect. It is Jo’s favourite plant at this time of the year so a regular walk to this far part of the garden is always on the cards.

For some reason many Tasmanian and South Australian plants have a look that typifies their geographic zone. Atherosperma is such a plant and very representative of plants from this region such as Eucryphia, Anopterus, and Drymis with leaves that are relatively small, leathery and scented when crushed. I have never been to Tasmania but apparently the oldest trees are over 30 metres in height, so leave plenty of room when planting so that your great grandchildren don’t curse you. With the largest in the UK still only about 12-15 metres tall size probably won’t be too much of an issue for a while yet.

Eunice

Eunice whistled through on Friday morning and unfortunately took out a few of the elderly and structurally unsound big old fellas and was even quite artistic in cleverly rowing up a pile of sticks as can be seen in the photo below. In the other image a twisted half of a beech will be a bit more of a headache to sort out. The oak is doing a remarkable job in holding the top but the continual rocking of more gales today is slowly tearing the base off the trunk of the parent tree. Not a good place to be hanging around even for dogs.

The largest lying beech log was a 170-180 year old survivor from the corner of the West Drive that was abandoned as the main access to the house in 1850 due to the steep incline below. So this is quite a sad historical loss. These big monoliths will be left in situ till the ground dries out later on in the summer. Quite big chunks these as can be seen with the 120 year old Douglas Fir behind. There is no frenzy to tidy up and make a complete horlicks of the ground and soil structure, best leave well alone for the time being.

The main garden survived Eunice in reasonable shape, much less severe than the last major blow in 1990. The plant collection is unaffected apart from a few important rhododendrons that will hopefully survive with careful layering of their stems. A few skanky conifers snapped off when the tail end of the depression moved through but overall we have been lucky and the garden should be ready for opening in Mid March bar any more serious storms .

Mahonia bealei

This superior Mahonia bealei form was a very treasured plant grown by the late Edward Needham, where it flourished carefully protected in his quarry garden. Most regular bealei varieties lose the spectacular glaucous leaf underside once they have grown on and matured, but not this character as can be seen in this image. It also turns out that it is pretty tough like most other Asian Mahonia spp. and doesn’t mind full sun and more exposure than where he grew it. The plant illustrated below is grown under a high deciduous canopy and flowers well every year in this type of location here in the south west even with our limited hours of sunshine.

The clonal name “Cornish Silver” has been coined for this selection and if anyone has room or the desire to grow bealei, then this is the one to search out, as it has been propagated by several nurseries and is available in the trade now.

Exbucklandia populnea

Strange name Exbucklandia, but makes sense when the taxonomic history reveals there was confusion with Bucklandia and this Genus had to find a new name…. There are a couple of small trees from Yunnan developing at different growth rates in the garden. One planted in the root competition of a large Sitka Spruce has reached only half the height of another in good soil 50 metres away indicating a liking for good conditions. The larger plant (about 10-12m tall), has just started to flower and fruit. I was still rather surprised recently though to see that it was performing at both ends at the same time. As can be seen from the emerging flowers there isn’t much of a horticultural show to be had, more a curiosity with the buds creeping out of a flattened envelope comprising a pair of enlarged stipules. The woody fruits show Hamamelidaceae with close morphology to Rhodoleia and even Corylopsis. From a distance the bold leathery foliage makes a statement and adds serious wow factor for garden visitors. The leaf shape varies with age, as young plants show off with pointed lobes, these gradually giving way to a more simple plate like shape with maturity. There are attractive reddish tints from this evergreen in spring as the older leaves are pushed off with the emerging young growth. Seed has been sent many times over the last 100 years but it is only recently becoming established outside its native SE Asian origins.

Polyspora longicarpa

In a mild winter such as this one the Polyspora spp. are the standout plants in the woodland during January. This image is of P. longicarpa which originates from Vietnam and is now large enough to make a real impact from a distance. Best grown in full sun in Cornwall with shelter from prevailing westerly winds where the display can be spectacular. There are also a couple of older trees from Yunnan in China at Tregrehan growing in more shade where the bud set isn’t as prolific, and these have even larger flowers at least as large as a decent fried egg. These first plantings were originally put in the mildest parts of the garden where I thought they had the best chance of surviving. But none have been lost to cold in 25 years and if there is a freezing spell the open flowers behave themselves by dropping cleanly. And as there is a succession of buds, (which is illustrated in this image), the display is soon cranked up again. The whole uplifting show lasts for well over a month in the gloomiest part of the year. There is a faint pollen scent to the flowers on a warm sunny day which attracts early pollinators. In the mid elevation evergreen forests of SE Asia these trees can grow large and form canopies in the wetter valleys, an amazing sight not to be forgotten in the late autumn/early winter.

Ancient Sweet Chestnut Tree Reborn

It was a sad day when one of the oldest trees in the park fell over in 2006. A behemoth of a trunk lay cast exposing a feeble root plate supporting not much of a canopy. It was in its last retrenching phase of life. Having survived for over 400 years and of huge importance with a bewildering array of invertebrates, lichens and fungi we were all keen to try and do something to keep the old fulla going. On close inspection I thought there may be hope if the top two-thirds of the tree was cut off, and the remaining trunk with remnant roots up-righted. Frank Tregunna with digger was quickly on hand to excavate a suitable hole and help to lift the bole back into an upright position. Now, 15 years later the tree has made a great recovery due to the ability of this species to regrow from epicormic shoots on the trunk. It makes a great conversation piece when viewed from the drive which after all is what objects in the park are all about.

Plant by plant

This heading coined by my mother refers to the pace of looking at a garden properly. My father and I would hesitate or grind to a halt beside each plant for varying amounts of time, depending on how much attention or discussion was required. The image here is of Eucryphia wilkiei in fruit today, which would have required much stoppage and thought to inspect properly. It is the first time this has fruited here, not many seed inside, a few in each for a total of about 12 seeds. Received from the National Collection holders in Co. Down at Seaforde, a wonderful garden restored by Patrick Forde.

Reported to grow to only 4-5 metres in Queensland Australia, this plant has already reached 3m and flowers regularly. It survived the “Beast from the East” with no damage so could eventually prove to be a winner for smallish gardens in mild locations. I’ve never been able to root any cuttings and with the garden gene pool of one clone hopefully the seeds will work and enable a small population to become established of this rare small tree.

Eucryphia wilkiei

A new beginning at Tregrehan

I have been wondering about sharing a few scenes and botanical events at Tregrehan for a while now. Winter seems like a good time to start this occasional blog with a freezing dawn parkland scene from a few years ago. A blog is an easily understood way for me to enter the 21st-century world of communications in a gentle manner. Opening the garden has been rather sporadic the last couple of years so this new dawn will hopefully interest people and show some of the events which visitors may have missed.

T.H. January 2022