Due to the uniqueness of growing conditions in the Douro and the indigenous grape varieties, there is still much to be learned. The Symingtons are at the forefront of a detailed investigation into the relationship between the vinifera varietals used in Port production and the rootstocks best suited to Douro conditions. Based on these interactions the best selection can be made for each site, matching the two components to optimise fruit quality for any given wine style. While this might seem relatively basic, the work is important as it simply hasn't been done by anyone else. Certain less-known but traditional local varieties are also under evaluation as some of these forgotten grapes have fascinating characteristics that can greatly benefit the Port blends. In addition, the phenology of these rootstock / variety combinations is also under evaluation to better understand their annual cycles and accordingly coordinate viticultural operations more effectively.
This project has since been extended into vital clonal evaluation - an area also in its infancy in the Douro. The Symingtons now have vineyards planted with 16 clones of Touriga Nacional, ten clones of Tinto Cão, eight clones each of Touriga Francesa and Tinta Roriz and four clones of Tinta Amarela. New clonal plantings are ongoing, with further investigation of improved clones of Tinta Roriz in particular planned for 2007. This work has been backed up with clonal microvinifications.
The potential effect of irrigation on Port grapes is another area that is virtually unstudied - in this case due to legal restrictions hitherto. The Symingtons have installed a small, custom-built irrigation plot specifically designed for precise evaluation of this question at an experimental level. This consists of ten sectors covering five different grape varieties where the timing and quantity of water applications can be controlled exactly. Each sector has an electronic timer and a flow-meter for accurate manipulation of water dosage, with a pluviometer on the dripper line to double-check watering periods. All this information is backed up with real-time meteorological data (including evapotranspiration) and soil moisture status which is transmitted instantly from the location via radio and internet.
In recent years the importance of matching appropriate canopy management techniques to the grape variety and the location has become increasingly well understood. Again, due to its deep traditionalism, the Douro has perhaps not embraced these advances as quickly as it might have done. Accordingly, the Symingtons have established vineyards enabling some of the most recent developments in trellising systems to be compared with their traditional counterparts. All of these can therefore now be evaluated under Douro conditions and using local varieties. These parcels contain six different trellising systems, some developed recently in the New World and others typical of the region, and the experiment is repeated on two quintas in different parts of the Douro. As with all these experiments, rigorous fruit analysis is carried out every year, and comparative microvinifications are possible in a dedicated winemaking facility.
In addition to these principal areas of research, Graham's is conscious of its responsibilities to protect the cultural and environmental heritage of the Douro, itself a UNESCO World Heritage Site. To this end, it runs an organic vineyard and is currently investigating the possibilities of using non-toxic alternatives to herbicides for weed control. It is also responsible for the recuperation of an area of ‘pilheiros' - the oldest method of establishing vineyards in the Douro. Under this system, in addition to the vines planted normally on top of narrow stone terraces, they are also grown horizontally out of small holes in these walls, forming a second, laid-down row of vines providing shade for those working on the terrace below. This is the only such vineyard set out in this historical fashion in the Douro, and probably in the world.
Symington Family Estates
Leading Viticultural Research
The Symington family is firmly committed to innovation, and over the last decade has conducted very substantial research in the field of viticulture.