What happens in the vineyard over winter?
Normally this is a very busy time for Hans as he must finish all the work before we leave overseas for our yearly wine promotion, visiting our distributors and discovering other wine regions around the world.
Being hands-on Hans, he is only willing to leave a dormant vineyard and once all the most important work in vineyard and winery is completed to hurry back when the vineyard awakens with bud burst.
But with closed borders everything is different this year. No travelling means plenty of time for all the jobs we have always postponed or shelved.
This is the time when we let the sheep graze in vineyard and headland for a natural weed control. A part of what they eat is for fattening them up and a part comes ‘returns’ as natural fertilizer.
Time for maintenance…
Trellising is a big part of post-harvest maintenance, because vines need supports to secure the wood and summer shoots within the training system to ensure proper ventilation and exposure. Each growing season, the trellis experiences pressure on its systems, and that leads to loosening of parts or even breakage. To optimize the performance, the trellis is best fixed when the pressure is off, and the vine is dormant.
Marlborough is infamous for its droughts and it strong North-West winds which add to it. Whilst we have a huge terroir advantage with our warm gravelly, sandy soil and its incredible drainage, it simply cannot retain humidity. That is why an irrigation system is essential to uphold vine health. However, as we do not want to increase yield we do irrigate sparingly and if we must, turn the irrigation on overnight simulating a rain. Our vines have a deep rooting system and can go quite some time before they show water stress as we forced the root system of the young vines (by deep ripping the soil) to look for their own water. Vines on a continuous drip irrigation scheme, which is normal for conventional vineyards to increase yields, will make roots just under the surface and therefore not able to bring valuable nutrients and flavours from the different sediments in the soil, which is vital to create more complex wines.
On the other side there is much talk about dry farming, but unless you are on clay soils (which is ok for early ripening varieties like Pinot Noir) with intermittent rain and no wind stress, water stress is affecting the vine and wine quality negatively. Water stress leads to reduced photosynthesis and optimum wine quality does not come from stunted vines with non-functional leaves. Fruit ripening may be delayed or suppressed, potentially decreasing quality and increasing risk of diseases. Also, wines made with grapes from drought stressed vines have typically been characterized by having dull or little fruit, less complexity, and relatively short life.
Our vineyard has a pressurised surface drip irrigation system. This system is fed by a pump that takes water deep from our aquifer. Water can be distributed to each irrigation block individually, by a system of solenoid valves, as required. Designing irrigation for our vineyard was particularly challenging because not even one row has the same terroir.
After the sheep left the estate there is a lot of maintenance… the sheep which roam the vineyard freely are easily frightened by any noise, our dogs or passing people, running off in a stampede and creating havoc with the wires and irrigation pipes. There is a lot of physical damage and pipes and tubing, hoses and emitters need to be checked to make sure they are all in working condition for the next growing season.
Posts & fence
From time to time one of our 24-year-old posts needs replacing and winter is the time to do this as there is no pressure from growing vines on the trellis system. Same with the fence, there is always a part which needs replacement after all these years.
Mechanical under-vine weeding
Once the sheep have done their job as natural under-vine weeder, its perfect to go through with the tractor and mechanical under-vine weed tool to delay weed growing further.
After pruning and once the sheep have left the estate all the wires which are part of the Trellis system have to be released from the clips and dropped to ground level. It means walking down the entire row (and vineyard) dropping the wires that have been clipped at the different levels of the posts during the growing season.
Pruning the fruit trees
In order to break up a monoculture of vines we have planted fruit- and nut trees as part our vineyard. They need to be pruned to grow a controlled crop and lower yield of flavourful fruit.
After pruning, winter spray of lime/sulphur as precaution for the widely spread powdery mildew and other bugs.
Lots to do and that does not even include the winery work…