Development of new grape varieties for 'cold climate'
Since 2020, Torben has collaborated with the Julius Kühn Institute (JKI) in Germany on the development of a series of new grape varieties for the Scandinavian climate.
See more about the project in Torben's articles in The wine press:
1) “Do the varieties we grow mature sufficiently well”: Vinpressen 2020-2
2) "Development of new varieties for Scandinavian viticulture": Vinpressen 2020-5
3) "Economics in the development of new varieties": Vinpressen 2020-6
4) "The first sensory evaluations of test wines": Vinpressen 2021-6
5) “Symposium on grape breeding”: Vinpressen 2022-6
6) "New grape varieties status 2022 - The sharp edges": Vinpressen 2022-6 (Søren K. Nielsen)
7) "Open house at Vrangbækgaard 2023": Vinpressen 2023-5 (Søren K. Nielsen)
8) "The hunt for new Nordic grape varieties 2023": Vinpressen 2023-6
9) “New Grapes for the Future”. Project status 2024 for FastGrapes: (English poster)
10) “Status after 5 years”: Vinpressen 2024-4
'FastGrapes'
The project, called “FastGrapes", is now so far that the first plantings of the selected grapes have been carried out in 10 places in Southern Sweden, Zealand, Funen, Northern Jutland and Northern Germany as well as at JKI in Rhineland-Palatinate in spring 2022.
One place is our vineyard here on Funen, where we are the first to follow the development of future grape varieties.
We have all the first 25 new varieties spread over 230 plants, i.e. 8-10 pieces of each (planted 2022). Then the next 10 varieties planted in 2023 and another 10 varieties in 2024, and in 2025 more varieties will be added. After this, work begins on selecting the best varieties.
Between the new varieties, a number of solaris have been planted as a reference variety, so that we do not have to compare the development of the new varieties with old established solaris plants, but can compare all the way with solaris at exactly the same stage of development.
The hope is, of course, that future successors to Cabernet Sauvignon and Pinot Noir are hidden among the experimental varieties, so that we will also be able to make excellent red wine in Denmark. And the selection of fully ripe green grapes should also be expanded to include more exciting flavors than 'only' solaris. 🙂
Crossbreeding and variety selection at JKI
At the Julius Kühn Institute, we start with thousands of crosses of selected parent varieties that are selected in the greenhouse for their resistance to a number of diseases. The surviving plants are then assessed for their cultivation characteristics and finally for the wine quality, assessed by making micro-vinification of the grapes from the individual plants. Only then can it be considered to start tests of the selected varieties with external winegrowers.
'FastGrapes' selections of early maturing varieties
After the plants have survived this far in the process, they are planted out in the open, where they have to show how they perform exposed to weather and wind. After a few years, when the plants are out of the juvenile phase and ready for the first harvest, they are assessed for general health, fruit set and maturity. Here it is that FastGrapes has been given permission by JKI to evaluate the plants a few weeks before JKI itself does so. In this way, FastGrapes can find and select the plants that ripen a few weeks before the plants that are otherwise selected after the normal harvest time in Germany.
In this way, FastGrapes hopes to find some new robust grape varieties that can reach full maturity in Scandinavian latitudes.
This selection is thoroughly described in the attached articles in Vinpressen. And then the selected 25 varieties have been propagated in a nursery to the approx. 1,000 grafted taproot plants that have now been sent for planting and assessment at selected winegrowers in Denmark, Sweden and Northern Germany. Over the next few years, the plants will be evaluated in the right environment, and the number will eventually be reduced to a handful of the very best varieties, which will eventually be registered as new grape varieties and put into production for general sale in nurseries.
The first plantings in Denmark
The first 25 trial varieties
Not all varieties bear the same amount of fruit this first season, but there are enough to make continuous maturity measurements throughout the season to help with the final selection. One of the varieties (FG14) stood out early as it was attacked by wasps in mid-August, long before the wasps took an interest in some of the other grapes in the field. It is also an indication of early maturation. We are considering having it tested in Norway.
We will try to do a micro vinification on the plants with the most fruit, so that we can get an early impression of what taste qualities they have.
Drive right and left in the gallery below. (September 2023)
Maturity measurements after 2nd season
During the weeks leading up to the harvest date on 1 October, measurements were continuously made of sugar content (°Oechle) and acidity. In the tables below, the final results can be seen for both the green and blue grapes.
In comparison, the reference variety 'Solaris' (green) achieved 104 °Oe, while 'Muscaris' (green) achieved only 65 °Oe and 'Bolero' (blue) achieved 61 °Oe on the same harvest date.
As can be seen, 3 green and 1 blue obtained levels between 98 and 107 °Oe and thus performed a maturity comparable to Solaris - grown in Denmark. And another 3 green and 5 blue followed close behind between 85 and 95 °Oe, which are also great numbers compared to the commonly grown grapes in Denmark.
The acid level was generally at fine levels between 5 and 8 g/l. And thus only a few of the first FastGrapes selections fell outside the expected levels of ripeness.
The plant spacing is 0.9m x 2.75m. All plants are on SO4 rootstocks. The plants with the highest yield gave approx. 1.5 kg per plant, while most gave around 0.5 kg per plant.
This is only season 2 where the first 25 varieties were only allowed to bear fruit in order to get some early maturity measurements. Next season (2024) the plants will have to bear the first fruit cane so that they can give a real harvest. At the same time, the next 10 selections will begin to set the first grapes - and a further 10 new selections will be planted.
The preliminary conclusion is that a roughly equal number (4-5) of green and blue test varieties out of the first 25 show signs of being able to achieve a maturity similar to 'Solaris', and thus it looks realistic that FastGrapes can reach the goal with developing new grape varieties for the Nordic climate, so that before long we can produce both excellent white wines from Denmark - and hopefully also great red wines. 🙂
Fruit canes are established for the first harvest
The first 25 trial varieties close to harvest
Drive right and left in the gallery below. (September 2024)
The next 6 trial varieties (FG26-FG31) 2nd season
Drive right and left in the gallery below. (October 2024)
