Tropical Ravine, Botanic Gardens, Belfast

The Tropical Ravine is a Victorian glasshouse fernery in Belfast Botanic Gardens, built between 1887 and 1889 to designs by Charles McKimm, the First General Superintendent of Belfast Parks. It sits to the east of the Ulster Museum and to the south of the Turner Palm House, within the Queen's Conservation Area and the Botanic Gardens Historic Park, Garden and Demesne. It is a rare surviving example of its type and unique in the province, enclosing a sunken ravine with a viewing gallery. The building remains in use as a glasshouse.

Origins and History

The Tropical Ravine was built on the site previously occupied by the Orchid and Fern House and Water Lily House — known collectively as the Tropical Glen — which had been constructed by the Belfast Botanic and Horticultural Society, formed in 1827. That earlier structure consisted of a single section (now forming the temperate section of the present building), measuring 97 feet long by 35½ feet wide (29.5 by 10.7 metres), with stone walls and a single-span glazed wooden roof. Features of its south-east gable wall remain visible on what is now the internal partition wall of the building.

The giant water lily Victoria Regina had been brought from London by curator Daniel Ferguson in 1851 and produced flowers two years later — the first in Ireland. In that same year the Society extended the existing fern and orchid houses to a total length of 63 feet (19.2 metres), with orchids and ferns grown in pots on open cast-iron grills; some of this original benching was later found during excavations in the present Tropical Ravine.

Charles McKimm had been trained at Lord Farnham's estate in County Cavan, gaining experience in vegetable gardens, flower gardens, and glasshouse plant collections. He joined the gardens as a gardener in 1874 and became curator three years later. He persuaded the Belfast Botanic and Horticultural Company of the need for a new glasshouse to accommodate the ever-growing plant collections, and construction began in the summer of 1887. It took two years to build and stock. When it opened in 1889, the Tropical Ravine was highly praised. The Marchioness of Dufferin and her party were among the first visitors that inaugural summer. Visitors entered through a doorway in the south-west gable and walked around a wooden lattice-railed balcony, looking down onto plants growing on banks and raised beds. At the bottom of the glen, paths meandered through the planting and led to water-worn stone steps, caves, a grotto, a waterfall, and a pool. The waterfall was activated by pulling a plumb bob on a pulley system. The largest cave extended to the outside wall of the building and had panels of patent 'Luxfer' glass prisms set into its roof, throwing light and colour into the space; these prisms, combined with candle illumination and mirrors set into the beds and walls, created theatrical effects. Photographs from the Welch collection in the Ulster Museum record these features. Some of the original tree ferns and banana plants are still growing in their original locations.

The Belfast Botanic and Horticultural Company was unable to continue financing the gardens and in 1895 sold them to Belfast Corporation for £10,500. McKimm was retained as Superintendent of Parks with responsibility for other Corporation-owned parks. He convinced Belfast Corporation of the importance of the fernery and undertook an enlargement programme completed in 1900, increasing the building's dimensions to 184½ feet long by 47 feet wide and 40 feet deep (56.1 by 14.3 by 12.2 metres). The internal features of the original house formed the basis of a temperate section, while the new north-east extension was used as a tropical or stove section. Banks to retain the planting beds in the new stove section were built using Scrabo sandstone quarried from Newtownards, County Down. Pools to house aquatic species were constructed against the north-east gable wall. A new roof was fitted at this time, consisting of steel structural supports, wooden glazing bars, and a lantern-style ridge housing the ventilation system.

McKimm also developed an original under-soil heating system in the original house (the current temperate zone), using hot-air flues fed from a stoke hole into large tunnels that decreased in size as they travelled around the building, ending as small tiled flues before venting through a chimney.

It is unclear how McKimm arrived at the innovative concept of the Tropical Ravine, as he left no notes on the subject. He may have been inspired by two comparable structures: a fernery at the Botanic Garden in Southport, England, built eleven years earlier, constructed from brick with a glass roof and planted with ferns and palms, its interior walls decorated with shells, tufa stone features, water effects, and mirrors — described in the 1878 Southport Directory as 'being unequalled in the North of Britain' and listed in 1972 at grade II — and a fernery at Ascog Hall on the Isle of Bute, Scotland, recorded in the Gardeners' Chronicle of 1879 as a fine glasshouse with a superb fern collection, constructed with a glass and iron frame roof resting on stone walls, with access down rustic stone steps with rockwork on either side, and listed in 1987 at grade B. The Belfast building differs from both in incorporating the distinctive sunken ravine.

The heating boilers burst during the winter of 1928/29, though the quality of the plant collections was maintained throughout the 20th century. During the Second World War, bananas from the Ravine were sent to the British Red Cross Society as a contribution to the war effort. The building was renovated in 1979, at which time the badly decayed roof was replaced with an aluminium glazed roof, resulting in the loss of the lantern-style ridge ventilation structure. The original under-soil hot-air flue heating system was replaced by hot water pipes threaded through the original tunnels. During the works the smaller plants were removed while the larger specimens were protected with a plastic cocoon. On 5 May 1983, following the completion of the renovation and the overall redevelopment of the Botanic Gardens, the Tropical Ravine was officially reopened by the Chairman of the Parks Committee, Councillor Andy Cairns JP, in the presence of the Lord Mayor, Councillor Tommy Patton. The British Airways Tourist Award was presented that year for the renovation work on both the Palm House and the Tropical Ravine.

The plant longest in the collection is a Dicksonia, or tree fern, approximately 150 years old, originally from the earlier fern house. One tree dominating the stove section, growing to forty feet, is the African tulip tree or fountain tree, Spathodea campanulata.

A note on the Botanic Gardens: the Belfast Botanic and Horticultural Society was formed in 1827. In 1828 a 14-acre site was purchased outside the town at the junction of the Malone and Stranmillis Roads and laid out by the first curator, Thomas Drummond. A botanical museum was opened in the grounds. The Society issued 500 shares at seven guineas each to help finance the project. Members of the public were charged one shilling for adults and sixpence for children; shareholders and annual subscribers were admitted free or at a reduced charge. Although the original intention was to provide a garden primarily for instruction and the study of plants, more popular support was soon required to raise the necessary finances, and from June 1838 onwards the gardens became a venue for outdoor activities and entertainment. The first glasshouses were built in the 1830s, and in 1839 work began on the Turner Palm House.

Exterior Description

The building is rectangular on plan, facing south-west, and is built into a slope to accommodate the sunken ravine. It is a multi-bay, two-storey structure of red brick with a steel and glass roof. The brickwork is in English garden wall bond with moulded brick and red sandstone string courses, plinth, and detailing throughout. Windows throughout are fixed-pane timber with segmental heads, chamfered reveals with stop ends, and sandstone keyblocks; red sandstone cills sit on moulded and corbelled brickwork detailing unless otherwise noted. Rainwater goods are galvanised steel. The roof consists of a steel truss and purlin structure with agricultural glass secured to steel rafters by clips and aluminium caps, with opening lights along the ridge.

The south-west entrance gable is symmetrical and single storey. It comprises a low brick plinth wall with brick piers to the corners; glazed timber doors are positioned at the far left and right; the remainder of the gable is fully glazed.

The north-west elevation is multi-bay, two storeys at the left reducing to a single storey at the right. Each first-floor bay has a single window; moulded brick and sandstone string courses run at various levels. A timber-sheeted door in a segmental-headed opening sits at the ground-floor left-end bay. The left corner has a chamfered plinth with long-and-short brick quoins. Bays are separated by paired vertical brick detailing that extends below the lowest string course to terminate in a moulded brick stop. Along the entire length of this elevation, except the left-end bay, a deep stepped red brick raised planting bed abuts the wall. The top left corner carries an Ulster History Circle plaque inscribed: 'Charles McKimm 1848–1907 First General Superintendent of Belfast Parks 1903–1907'.

The north-east gable is two storeys and three bays. At ground level there is a central door with single windows in the end bays. At first-floor level each bay has a single square-headed window surmounted by broken triangular sandstone pediments; the central bay has a broken segmental pediment instead and is set forward. Above this, a single arched window sits within the square gable. A brick flue rises from ground level to the left of the windows in the central bay. The ground floor has a chamfered plinth with long-and-short brick quoins, and string courses as elsewhere, with a cill course at the window in the pediment. Bays are separated by detailing as on the other elevations. The parapet is raised, stepped, and segmental, with sandstone copings and kneelers.

The south-east elevation is multi-bay, two storeys to the right reducing to a single storey to the left, and is treated as the north-west elevation but without a door.

Setting

The building stands in Belfast Botanic Gardens, built into a slope, with the Ulster Museum to the west and the Turner Palm House to the north. A large open lawn lies to the east, separated by mature planting, with trees to the north and south.