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Belgian Oak Open Days 2025

The last time we visited oak collections in Belgium was in 2011. We visited two collections that day, Plantentuin Meise (then still named the National Botanical Garden of Belgium) and Arboretum Wespelaar.
It's high time we took another look at the Belgian oak collections. This time the event will take place over the Ascension weekend, 29 May – 1 June 2025, four days.
The program is as follows:
Hemelrijk
Hemelrijk (Kingdom of Heaven) is the second garden of the De Belder family, after Kalmthout (now owned by the province of Antwerp). The brothers Robert and Georges De Belder bought the domain in 1960. With Robert’s wife and famed plantswoman, Jelena De Belder-Kovačič, they planted thousands of plants over the years. They were also assisted by their friend, the famous landscape architect, Russell Page. The domain is now owned by Robert and Jelena’s children. It is probably still the largest private dendrological collection in Belgium. The collection includes some notable oaks. Philippe de Spoelberch (see Arboretum Wespelaar) will be our guide for this visit.
Three Public Gardens in Brussels
The morning will be devoted to an urban walk that will take us through three gardens near each other: Parc Tenbosch, Jardin du Roi (King’s Garden) and Abbaye de la Cambre. Only Tenbosch Park was a private dendrological collection before becoming a public park in 1982. All three parks, however, boast a fine collection of trees and shrubs, including oaks. We will also walk by the Brussels champion Quercus cerris.

After the walk, we will drive (45 minutes) to Arboretum Wespelaar.
Arboretum Wespelaar
The arboretum was started in the early 80s by Philippe de Spoelberch as an extension of his garden, Herkenrode. It was donated to the Foundation Arboretum Wespelaar in early 2000. Arboretum Wespelaar employs professional and enthusiastic staff, headed by Dr. Koen Camelbeke, and is now considered as one of the best botanical gardens in the world. Philippe de Spoelberch, assisted by Joke Ossaer, will be our guide for this visit. The IOS visited the garden in 2011.

Kasteel van Widooie
Widooie is a small village in the province of Limburg, and it now belongs to the municipality of Tongeren, a city that goes back to Roman times.
Norbert de Schaetzen, current owner of the Castle of Widooie, has undertaken a vast replanting program of its park, planting mainly oaks sourced by Antoine le Hardÿ and Dirk Benoit (Pavia Nurseries), as well as some younger plants donated by Arboretum Bokrijk. The collection is young but deserves a visit. Many plants are mislabeled, and attendees will be called upon to correct some of the labels.

After the visit to Widooie, we will drive (45 minutes) to Bokrijk where we will have lunch before visiting their oak collection.
Arboretum Bokrijk
Arboretum Bokrijk, located in the province of Limburg, is part of the 550-hectare Provinciaal Domein Bokrijk, best known for its Open-Air Museum. This museum showcases Belgium’s cultural history through authentic historical buildings and living exhibits. Next to this rich cultural heritage, the Arboretum shines as a true botanical treasure. Spanning 18 hectares, the Arboretum forms the heart of Bokrijk’s botanical collection. However, remarkable trees are also scattered throughout the castle park and the vast grounds of the estate. Established in 1965, the Arboretum is home to a wide variety of trees, shrubs, and herbaceous plants.
Bokrijk has the largest oak collection in Belgium, a legacy largely attributed to Jef Van Meulder, whose pioneering efforts laid the groundwork for the Arboretum’s diversity. Sven Bronckaers, Jef’s successor, will be our guide during this visit.

Plantentuin Meise (Meise Botanic Garden)
Meise Botanic Garden was until 2014 the National Botanic Garden of Belgium. It was then transferred to the Flemish Community. The garden is in the grounds of Bouchout Castle in Meise, Flemish Brabant, just outside of Brussels. It is a very large botanical collection, but about half of its living collections is in greenhouses. The garden has a sizeable oak collection that the IOS visited in 2011.

Most trees and shrubs in the collections listed here can be found on the website Botanical Collections.
Registration for this event will open in early 2025, but please write now to the Tours and Events Committee if you are interested in participating.
Charles Snyers
Belgian OOD Coordinator
All pictures © Charles Snyers, except when otherwise indicated.