Location
The Gloeckelberg Grand Cru is mostly located on the territory of Rodern, and for a small part in Saint Hippolyte. The sloped hillsides are facing south and south-east. If the upper part of this Grand Cru is characterised by steep slopes, they pan out in the lower part, creating a funnel effect which guarantees good air circulation.
Ce terroir se situe à l'Ouest de la faille vosgienne, à l'extrémité Nord du champ de fracture de Ribeauvillé. When the upper Rhine plain collapsed, the huge tectonic stress created reliefs and large fault offsets.
Soil
The parent rock is made of so-called porphyroblastic granite from Thannenkirch, recognisable by its large crystals of potassium feldspar blended with its other major components such as quartz and mica.
When granite is exposed to weather conditions, they alter and while breaking up, they shape into loose mantles called arena whose thickness can vary depending on topographical exposure. These granular, coarse sand soils create acid chemical reactions making the soil turn brown.
Sur le haut du lieu-dit des débris schisteux et gréseux se mêlent au granite. These soils have low useful water supply and can suffer from drought during warm years. At the bottom of the slope, the accumulation of colluvium provides better water supply, notably at the end of the summer.
Microclimate
Although the region of central Alsace is sheltered from the Vosges mountain range where its peaks are the highest (Brézouard, 1228m) it is one of the regions with the lowest rainfall in France. On the Gloeckelberg the rainfall is between 600 and 700 mm per year. Moreover, the south-east hillside exposure with a perfectly open horizon towards the east and steep slopes especially near the top of this moderately-high site, provide this Grand Cru with excellent heat conditions. In addition, the soil heats up easily during the spring, contributing to all the best conditions for early-maturity and great ripening of grapes.
Grape varieties
Pinot Gris and Gewurztraminer represent over 95% of the wines produced in this Grand Cru.
These two grape varieties are particularly suited for this terroir: the early-ripening and the water stress stop the grapes growing and allow them to obtain perfect maturity.
Also, the topography and microclimate of this lieu-dit often cause raisining which makes the harvest even more concentrated.