Trévarez kitchen-garden greenhouses (Labotanique great greenhouse)

James de Kerjégu, born at Trévarez in 1846, a former diplomat and chairman of the Finistère general council, had a château built between 1893 and 1907 on a promontory above the canalised River Aulne, beside an older manor house of the 16th and 17th centuries. He entrusted the house to the Parisian architect Walter-André Destailleur; the Mérimée heritage database also links the estate to the landscape architect René-Édouard André. The château received every modern comfort, from central heating to electricity generated in the outbuildings.

The same taste for modernity reached the working gardens: to keep his table supplied with fresh produce, Kerjégu built extensive greenhouses with adjustable hot-water heating, and the official site recalls that several of them were heated. Kitchen garden and orchard were deliberately kept out of sight of the house. Their patron died in 1908, shortly after the works were completed.

Occupied by German forces from 1941, the château was bombed by the Royal Air Force in 1944 (on 30 July according to English Wikipedia, on the night of 4 to 5 August according to the French article) and then abandoned together with its park. The Finistère council bought the estate in 1968 and reopened the park in 1971. Since 6 April 2009 the estate, greenhouses included, has been listed as a monument historique. The old walled kitchen garden opened to visitors in 2014, and the Labotanique moved into the largest greenhouse in 2015.

The greenhouses belong to the walled kitchen garden north-east of the château, laid out, like the orchard, to remain invisible from the house. The 2009 listing order describes the group: greenhouses set in their entirety against the north wall of the kitchen garden, then, in the adjoining orchard, three cold houses and one hot house. The same order protects the ground and enclosure walls of both plots, the central basin of the kitchen garden and the estate's hydraulic installations.

That heating, run on hot water and adjustable to the crops, set the Trévarez houses apart from simple unheated shelters and served the produce grown for the château's table. The cadastral plan, as used by OpenStreetMap, still traces their footprint inside the enclosure.

Of the former working garden only the greenhouses, the enclosing walls and the paths survive, restored and opened by the département. The largest house was refitted in 2015 to receive the Labotanique, whose twelve hands-on exhibits now fill the space under glass.

Under the great greenhouse, the Labotanique is not a living collection in the usual sense: it is a discovery space about the plants of Trévarez, designed for families and school groups, which explains through twelve hands-on exhibits how the park's plants live and grow. The heated houses, once devoted to early vegetables and table fruit, thus serve as a gateway to the estate's collections.

There are three of them. The camellias, including about 160 century-old specimens, earned the park the International Camellia Society's "Garden of Excellence" label in February 2016. The rhododendrons form the French national collection of hybrids of the genus, recognised in 1992; the official site counts 600 varieties, many from the English Hillier nurseries, while French Wikipedia puts the figure at around 700. The hydrangeas, the third collection with about a hundred varieties, line the hydrangea walk near the château, the former stables and the old kitchen garden.

The main avenues are planted with ericaceous shrubs, andromedas, skimmias and osmanthus, and with exotic trees, the flowering seasons following one another by quarters, camellias in winter and hydrangeas in summer.

The Trévarez departmental estate, 85 hectares five kilometres south of Châteauneuf-du-Faou, takes half a day. The kitchen garden and its greenhouses lie north-east of the château, close to the hydrangea walk and the former stables, whose restored glass roof hosts exhibitions and festivals. The château presents the "Bâtir un rêve" interpretive trail and an Art Nouveau bedroom of 1903 recreated in 2019; the Saint-Hubert chapel and the formal, Italian and Japanese-style gardens round off the walk.

Highlights punctuate the year: camellias in late March, rhododendrons in May, hydrangeas in July, then "Noël à Trévarez", an evening trail from late November to early January. The Labotanique is aimed first of all at families.