PGG Study Trip to Belgium

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Tervuren ArboretumWell this was a treat, I took up a last minute spot on the trip (hope theleg is recovering John) Tuesday evening and met the gang at St Pancrasfor 10am on the Friday. How lovely to be able to just turn up and behanded tickets and know that everything has been organised for you,instantly relaxing. We emerged at the other end to be met by our coachand the driver who would ferry us around for the weekend trip. Wewere whisked immediately to our first port of call, Tervuren Arboretumwhere we were met by our guide Wilfried Emmerechts, who brieflyexplained the layout of the huge site. There was way too much for usto see in one afternoon as the Arboretum covers about 100 hectares;not so much a collection of trees as a collection of forests! Our tour wasto take in the New World; essentially North America.

To my personal delight we set off for the North West coastal areafirst, it was gently misting with rain by that point, to the generaldisappointment of the group I think, but I loved it. The magnificenttemperate rainforest trees looked fabulous with their tops in the mistjust as they are in their natural habitat for a good part of the year, itwouldn't have been right to walk amongst them in bright sunshine. Allit needed was a glimpse of a black bear and the call of a raven or twoand I’d have been transported back to the BC coast. Most of the treeswere planted at the turn of the 20th century so it was fascinating to seethe comparative growth rates of these giants in just over 100 years. Thered and yellow cedars with their elegant swooping foliage were spacedfurther apart than you’d see them in a virgin North West forest andbecause we were walking on the edge of the forest the trunks were‘clothed’ almost to the ground, a treat to see but, like a freshly washedand brushed border collie, you know they don’t usually look like that.Most of the Douglas firs were just developing the truly fissuredelephant skin texture on their trunks, for these were actually 100yr old,100ft kids... in the scheme of things they were just starting out; manyof these trees have the potential to live for between 1000-1500 yearsand reach 60-80 metres, hard to believe as we craned our necks that wewere in a nursery! Crunching on, with a mixture of fabulous conesbeneath our feet, we were taken via beautifully laid out swathes ofwalks and glades, interspersed with natural lakes, through NorthAmerica. The weather played ball and as we headed to the SouthernStates and over to the East Coast the sun struggled through. By thetime we had a glimpse of the first maples, the light was picking out thegently colouring foliage (as in the UK, autumn colour was behind thecurve for the time of year).

This is a beautiful collection of forests and a wonderfully naturallooking site as Arboreta go; I loved the fact that it’s free for everyoneto visit, it must be fabulous to live close by and be able to use it as arecreational resource. I look forward to seeing how it develops, Wilfiedis keen to start some naturalised underplanting which will ultimatelycut down the maintenance; they spend a lot of time removing bramblesand undesirables at the moment. If you are near Brussels it’s well wortha trip, www.arboretum-tervuren.be but be sure to take a map and a picnicwith you. Some would say it is under-developed as it has no visitorfacilities but given that it doesn’t rely on entry fees for funding it hasthe luxury, I would say, of being refreshingly free of signage and ‘stuff ’and consequently it truly feels like an extension of the countryside.Iris Lynch

PGG trip to Belgium – members memories...Autumn 2014

Arboretum Kalmthout Our visit on the Saturday morning was to ArboretumKalmthout located on the outskirts of Antwerp. The 12hagarden was originally created as a nursery in the 1850s and alegacy of straight paths and trees and shrubs planted in rowsreflects this past. In 1933 the site was purchased by Robert deBelder, a diamond dealer, and his Slovenian wife Jelena whowere both passionate collectors of plants, particularly trees andshrubs, and made many plant collecting expeditions primarilyto Japan and the USA. They also carried out many experimentsin plant breeding with the best specimens being planted here atKalmthout. They had a particular interest in Hamamelis and thearboretum has the best collection of this genus in Europe, withparent plants of some of the best known cultivars including‘Jelena’ and ‘Luna’. The arboretum has an annual Hamamelisfestival in February, which regularly attracts 15,000 people –quite a challenge for the grass paths. The arboretum was sold tothe state in 1987 following a huge banking crisis and is todayfunded by local government, income from visitors, and byselling seed to the nursery trade. It currently employs sixgardeners, four of whom are full-time, and lots of volunteers.We were guided around the garden by director Rob Van Bauweland we were shown a dizzying array of fine specimens, so I willjust pick out a few highlights.

We were shown a number of specimens that originated inthis garden including Prunus ‘Jacqueline’, which has an AGM,and Hydrangea paniculata ‘Unique’ and ‘Brussels Lace’. Awonderful Picea abies ‘Nidiformis’ caught many people’sattention, it apparently requires some serious tree surgery skillsand a lot of props to prevent it collapsing. Although theautumn colours perhaps weren’t as good as they could havebeen, specimens of Pseudolarix amabilis and Taxodium distichumhad coloured well. There was also plenty of fruit on displayfrom the dark-red crab apples of Malus ‘Red Pillar’ to variouslycoloured Euonymus including yellow E. myrianthus and brightpink E. europaeus ‘Fructo-Coccineo’. The bark of variousStewartia and Abies squamata also attracted attention as did thehuge leaves of Platanus x acerifolia ‘El Gordo’. Perhaps thebiggest talking point was a five-legged Tillia created bygrafting five lime rootstocks onto a young lime tree andthen once a union had formed cutting though the stem ofthe original tree to give the appearance of it being on fivelegs. This method can apparently be used to save treeswhich have been ring-barked by strimmer or by wildlife.Frances Keeton

Picea abies 'Nidiformis'

Euonymus myrianthus

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PGG Study Trip to Belgium

HemelrijkWe continue our arboricultural feast with a visit to Hemelrijk, aprivately owned arboretum which has become the trial andgrowing on ground for the constricted acres of planting atKalmthout. Our ten minute walk from the coach park to the gardenentrance was minus the dulcet tones of our Chairman whomanaged a regal wave from the front seat of a chauffeured limo,very nice for some!

Rob Van Bauwel, was again our guide. His sheer knowledge andenthusiasm for trees was truly engaging to us all, coupled with asharp wit; we were spellbound. Hamamelis, oak, Magnolia andHydrangea were the main focus, the garden boasting many namedcultivars bred by them over the years, along with mature specimensof unnamed cultivars unworthy of introduction (you wouldn’t havenoticed why). There are 24,500 labelled plants in the arboretumwith 8,500 labelled species.

Originally the site of Antwerp Abbey, Hemelrijk boasts majesticbeech and oak avenues, some 150 years old. It was acquired in1968 by the present owners who engaged Russell Page to introducean English landscape, mechanically moving and arranging thetopography to better suit the growing of trees and shrubs. This hasproduced a natural landscape to set off the trees and shrubs to greateffect, a plantsman’s paradise.

We were also shown around the walled garden, which was equalto the parkland in its quality of maintenance, all that we saw wasmaintained by the owners, with staff employed only for hedgecutting and mowing. The formal hedging used around the bedswas Ilex crenata, some 20 years old. Rob, our guide, agreed it wasn’tthe answer to finding a replacement for the traditional box andblight. We were reliably informed that a colleague of Rob’s, workingat Ghent University, has propagated a Buxus that is resistant toblight and which will be marketed in 2015. You heard it first here.

Alongside the walled garden was a woodyard but not like anywoodyard I’d seen before, it was an art form in itself. Plankedwood, root stumps and crosscut trunks all drying naturally,arranged to beautiful effect. This was one of the best garden toursI’ve been on, for me it was the highlight of the weekend. Steve Elstub

HerkenrodeIt was a privilege to have a guided tour of the private garden atHerkenrode. Philippe de Spoelberch (the owner of Stella Artois)only opens his garden occasionally; we were lucky enough to beshown around by Head Gardener, Christophe Crock. The gardenbacks onto the Spoelberch’s famous Arboretum Wespelaar, which wevisited afterwards. If you know anything about the arboretum thenyou will expect some great things from this private garden, and itdelivered just that. The garden is 10 hectares (approx. 25 acres) ofstunning and rare plants, mainly wild-collected woody plants fromChina and elsewhere in Asia. The east side of the house is a formalJacques Wirtz design, with lawns and borders edged with lowhedging, while the west is a naturalistic arboretum of many rare andinteresting plants. The front looks onto a small lake and along a vista.All this is surrounded by an arboretum of select trees, shrubs andbeyond this, oak woodland.

We came in October to see the autumn colour and Herkenrodedid not disappoint. Christophe began by showing us some stunning‘autumn colour’ trees and shrubs near the entrance to the back of thegarden. The star unusual plant of the trip for me was Sapiumjaponicum, a shrub in the Euphorbiaceae family, grown from seedcollected in South Korea and showing stunning red tones. The seed-grown trees and shrubs at Herkenrode are selected for strong autumncolour and shape from large batches, the rest discarded, resulting ina garden with stunning displays in autumn. Christophe showed us aParrotia persica to illustrate the results; I don’t think any of us hadever seen such intense red autumn colour in a Parrotia before and thehabit was more upright than most I have seen. The rest of the gardenhad more of the same; I could easily fill the page with a list ofstunning ‘autumn colour’ trees and shrubs.

In the formal areas the hard lines of freshly clipped hedging weresoftened by the contrasting trees and shrubs within. One contained arow of large magnolias, which Christophe explained was left overfrom what was once a bed of seedlings of various crosses raised byPhilippe, who has a keen interest in magnolia hybridising. The worstcrosses were culled and the remainder still stand today in theiroriginal places. Something I had never seen before was the use ofbamboo canes around the base of trees to deter deer from rubbing upagainst them; the smooth surface gives them no satisfaction, so theygive up! Before crossing the vista and entering the woodland gardenof rarities we passed a huge Liquidambar styraciflua, one of the largestin Belgium, just beginning its autumn show. While walking throughthe woodland garden I was overwhelmed by the range of interestingplants. I must mention Illicium floridanum ‘Halley’s Comet’, a closerelative of star anise (Illicium verum), in flower. As well as the treesand shrubs, Christophe had begun to establish an herbaceous layer.A drift of Cardiocrinum gigantium, various wild collected Zingiberaceaeincluding Zingiber mioga and ferns such as Woodwardia unigemmataand Adiantum pedatum were just a few. The tour was finished off bya stunning display of autumn colour from a group of acers.

This was a thoroughly enjoyable visit which made me realise thatI will never stop learning, and that beer and gardens do go together!I would like to thank Christophe for his time and sharing hisknowledge. He is a true plantsman with incredible expertise, who ismore than happy to share with like-minded people and that includesseeds (and plants). I would also like to thank Colin Roberts whomade it all possible by organising the visit and transport for us all. Rupert Harbinson

Tour guide Rob Van Bauwel,

showing aSlovenian hay barn

built by workerssome 70 years ago

Woodyard atHemelrijk

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PGG Study Trip to Belgium

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Arboretum WespelaarA beautiful double avenue of mature lime trees brings us from Herkenrode Garden to ArboretumWespelaar. Philippe de Spoelberch, a passionate dendrologist, started his botanical collections atHerkenrode in the 70s. In order to accommodate more plants, he then bought 20 hectares ofbordering land, on what would become in 2011 the Foundation Arboretum Wespelaar. Thearboretum holds specialised collections of 2000 different taxa and cultivated varieties of trees andshrubs from around the world, hardy in Belgium. The three largest collections are probablyRhododendron, Acer and Magnolia, but other favourites are Quercus, Betula, Tilia, Carya andStewartia.

Many interesting cultivars have also been bred and named here. Most of the selections comefrom on-site seeds and crosses, but also from plants that the arboretum bought or received as gifts.They are named after a period of observation and comparison, when they show exceptionalqualities and are worth introducing to the market. Some selections of Magnolia and Rhododendronhave proved to be particularly successful.

Together with other world’s major botanical institutions, Arboretum Wespelaar aims toimplement practical conservation of plants. The arboretum holds 166 taxa appearing on the RedList of threatened plants. Among these are the critically endangered Torreya taxinifolia and Piceamartinezii, as well as the beautiful (but uncommon in cultivation) Magnolia sargentiana. Thefantastic Franklinia alatamaha, extinct in the wild, was in full bloom and just its contemplation wasworth the journey itself. The comprehensive, diverse dendrological collections provide not onlybreath-taking all year-round interest, but also the opportunity for ornamental display and plantingon a vast scale. Aesthetic elements of design and structure have been introduced, such as statuesand the Artois Pond at the focal point of the arboretum. Radially from here, gentle meadows andmore austere woodlands gradually take over, in an ascending progression of colours, textures andinterest.

In the Marnef Wood, trunks of the mature native oaks (Quercus robur) give the structuralfoundation of the woodland, providing a protective canopy above an understory of maples andmany other smaller trees and shrubs. In autumn this is like a gothic cathedral set on fire. Specimensof Betula lenta, Carya glabra and Pseudolarix amabilis displayed a lovely autumn colour. Linderaobtusiloba had the most beautiful foliage, with elegant orbicular leaves, terminally trilobed, turningyellow in autumn. Hardy, unusual shrubs and trees are successfully cultivated and displayed.Euptelea pleiosperma, Disanthus cercidifolius and Sapium japonicum could be grown in British gardens.

It has been extremely interesting to compare the different horticultural tastes within countries,getting new ideas and inspiration. Wespelaar is an inspiring site, displaying extremely highstandards with all-year-round interest. It would be wonderful to come back here again with thePGG in March for the magnolias, or in July for the bloom of the many Styrax and Halesia speciesin the collection. My name is already on the list for the next visit.Giulio Veronese

Illicium floridanum‘Halley’s Comet’

Maples at Herkenrode

Sapium japonicum

Bamboocanes to

deter deerdamage Group photo in front of the Arboretum Wespelaar visitor centre

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