Visit to the Botanical Gardens of Leiden and Utrecht

As our first trip abroad after the pandemic, my partner Nick and I went to the Netherlands to visit Hortus botanicus Leiden, the University Botanical Garden in Utrecht and the Arboretum Trompenburg in Rotterdam. I hoped to see tropical ferns at the first two and I had contacted Miguel Fernandez Voortman, an Exotic Fern Group member in Leiden, and Marco de Jong in Utrecht beforehand.

Hortus botanicus Leiden is one of the oldest botanical gardens in the world. Founded by Clusius, it was a ‘physic garden’ of medicinal plants. However, over the years large collections of foreign plants were cultivated, especially those from the Dutch East Indies

(Indonesia). Siebold’s house is just a few doors away from the Hortus. As a collector of medicinal plants, he was one of the very few explorers allowed into Japan in the three centuries of Japan being closed to foreigners. The house is now a museum of his ethnological artefacts and herbarium specimens.

The hothouses at Leiden consist of a large modern building (Figure 1) and a series of older buildings culminating in a large, heated pool for a Victoria waterlily (Figure 2). Entry is through the new building with a large variety of tropical plants and trees in the ground. There is a high-level walkway over the canopy and winding paths at ground level (Figure 3). Supporting pillars are clad in peat blocks (these are still available in the Netherlands) and the building is heated and humidified. At some time, a visitor released tiny 2 cm tree frogs which are surprisingly noisy and make for a very tropical atmosphere. In this building is a large Cibotium schiedei and many smaller ferns such as Pteris semipinnata (Figure 4). The canopy has thickened over the years and some ferns, which I remembered from previous visits, had not thrived in the diminished light and had disappeared.

On leaving the new building there used to be an older glasshouse with shelves of tropical ferns and orchids. It was these that I was keen to see again as I wanted to do some comparisons between species of Goniophlebium. Unfortunately, what was previous a very packed glasshouse, was now half-empty (Figure 5) and most of the ferns had either gone or were in groups ready for shipment elsewhere (Figure 6). Miguel told us that the glasshouse had developed a crack in the floor, necessitating removal of the ferns whilst repairs were undertaken. In the meantime, an Amorphophallus titanum had

come into bloom and had been exhibited in the space. This had pulled in over 5000 visitors, all of whom had paid their entry fee. At a time of financial stringency, this made the idea of using the space for displays of popular plants very attractive. So, the long established fern collection had been dispersed to other botanical gardens and the zoo at Blijdorp, Rotterdam.

There was still a row of shelves along one side of the glasshouse with pots

of ferns including Drynaria and Pyrrosia. Miguel told us that he was keen to catalogue these plants and ensure that the labels were correct. He was also optimistic that some of the epiphytic ferns could be displayed elsewhere in the Hortus.

The outdoor collection of over 300 varieties and species of ferns is maintained by Miguel, Harry Roskam and one other gardener. They only work for one day per week as volunteers. The area of the fern garden is being increased.

In contrast to the ancient Hortus botanicus, the University Botanical Garden in Utrecht was created in the University Science Park in the early 1960s. It contains a large defensive fort on an island, and it is this island that has been made into the largest rock garden in Europe. The rockery has three permanent gardeners with Connor Smith as the lead. Marco de Jong, who showed me around, has just completed his training and is in a probationary period, hoping to be taken onto the permanent staff. Ferns are not a special interest of this botanical garden but there are hardy ferns planted around the moat of the island, with excellent care and labelling of all plants (Figure 7).

In terms of tropical ferns, there were some in the very large hothouse and adjacent glasshouses (Figure 8). Here the labelling was not accurate, and Marco was hoping to correct this. The very large Angiopteris evecta that I had seen on previous visits had been cut back and moved away from the central pond to allow in more light. There was a large Sphaeropteris cooperi (syn. Cyathea) and many familiar ferns such as Cyrtomium,

Phlebodium and Anemia species (Figure 9). However, I found one which I had not seen before labelled as Microsorum punctatum. I knew this was incorrect and took photos which allowed me to identify it as Leptochilus wrightii (Figure 10). I also studied a plant labelled as Blechnum occidentale and determined that it was probably Blechnum

appendiculatum, as it had a minutely hairy rachis rather than being glabrous (Figure 11).

These were very enjoyable and worthwhile visits, though the dissolution of the tropical fern collection in Leiden was disappointing. I am very grateful to Miguel, Marco, Connor and Harry for spending time with us.