Alan’s Blog – Solaris
Helme Edge Vineyard at 53 North, and 226m altitude in West Yorkshire with stunning
Pennine views owes its existence to the PIWI grape variety Solaris which has thrived under
our challenging conditions to give grapes that make outstanding still white and sparkling
wines.
The hybrid vine was developed at the Freiburg Wine Institute in 1975 by Norbert Becker in
a programme dedicated to finding vines with good cold climate tolerance, early ripening
and in particular, resistance to disease in the shape of the mildews and assorted fungal
maladies that plague vineyards growing traditional varieties. Solaris’ parents are Merzling
and Gm 6493 (Zarya x Muskat Ottonel). Many other white and red varieties have since
been developed and are being planted in England particularly newer red varieties,
Cabernet Cortis, Cabernet Noir and Divico.
These varieties are collectively known as PIWIs, an acronym for the German noun
Pilzwiderstandsfahig meaning resistant to fungi and hence requiring no or very little
spraying with fungicides, a significant cost and environmental benefit.
Solaris is grown in the UK, Sweden, Denmark, Belgium, the Netherlands, Switzerland and
Germany. Sweden deserves a special mention for the recent growth of a viticulture
industry dominated by still and sparkling Solaris.
The early ripening characteristic of Solaris makes it eminently suitable for growing in
England and Wales, particularly in the north where the climate makes growing classic
varieties such as Pinot Noir and Chardonnay problematic, although many vineyards are
experimenting. For new entrants Solaris is the “go to “grape for the north. Bud burst for
Solaris is about a week before the average, leading to one of the earliest harvests in the
month of September. It also has high must weight potential reaching as high as 100
Oeschle (sugar levels) depending on climatic conditions.
Plantings of Solaris in England and Wales have grown quickly to around 110 hectares
(2024) up from 24 hectares in 2015. It is now the sixth most widely planted variety. With
such a wide range of potential picking points, Solaris is suitable for sparkling wine when
picked early at slightly higher acidity. In the still wine range different levels of ripeness
give profiles ranging from citrus through to more aromatic character. Sweet Solaris wines
of high quality have been made by stopping the fermentation at around 10%ABV leaving
significant residual sugar.