How do they plant new vines?

With an old tractor, 3 guys, and sophisticated GPS it would appear. It is a methodical and slightly hypnotic process to watch.

 As you can see from this image, the tractor has a structure around it, on which two people can sit. The tractor makes a hole, one person (the man in blue) puts a vine in the hole, with another person (the man in the white t-shirt) adding the stake which will provide support to the new vine as it grows and establishes itself.

 The man walking behind is the tractor driver! It was fascinating to watch the tractor drive itself along the rows, guided by GPS.

 As you can see from the video, the walking-man only leaps into action when they reach the end of a row. Then he gets into the tractor cab, raises the machinery the two planters are sitting on, and reverses the tractor all the way back to the start, ready to plant the next row.

 And so they continue. Until the whole parcel of planted with vines. All very neatly and precisely laid out.

Why use GPS when planting new vines?

GPS is used to ensure the vines are planted exactly where they are required. The exact number of vines per row, equally spaced and each row the same distance apart.

The spacing between rows is important, it is crucial that a tractor can fit between the rows for efficient management of the final vines. Vineyard tractors are noticeable narrower than tractors used on normal arable farms.

Each wine region tends to have a standard distance between vines so tractors can be used interchangeably across plots.This very narrow tractor is in Burgundy.

Vine density is crucial for wine quality

Most wine appellations have strict rules as to the density of vines, expressed as number of vines per hectare. This is to maintain the quality of the final wine. The higher the density, the more competition there is between the vines for water and nutrients, and the more stressed the vine. The right amount of stress means the quality of the final wine increases.

Since the distance between rows is largely defined by the size of the tractors, to achieve the densities desired, the vineyard owner can only vary the number of vines they plant per row.

Why do stressed vines make better wine?

Vines are naturally vigorous, if they are not stressed, for example they have enough water, they will put their efforts into growing shoots and leaves.

However, if there isn’t enough water, they will go into survival mode. To survive they want to attract birds to eat their grapes, thereby spreading their seed to grow elsewhere. Focusing on producing the best, sweetest grapes is the best way to attract the birds. With the added benefit of providing winemakers with the best grapes for wine.

Why do vine densities vary?

Densities are partly driven by the climatic conditions of the region.

For example, Pauillac in Bordeaux south-west France usually has sufficient rain throughout the year for the vines, therefore, to ensure the vines are stressed, competition needs to be introduced between them. To do this, vines are planted at high densities (around 10,000 vines per hectare) to ensure there is competition between the vines for water.

Whereas in Priorat in north-east Spain, it is generally very hot and dry in summer, so the vines are already stressed by the lack of water, therefore they plant much lower densities (2,500 to 3,000 vines per hectare) allowing the roots of each vine to grow over a large area to seek out water and nutrients.

Vine density and quality

One of the many things a wine appellation, or AOC will set for wines that are to be labelled under their AOC is the density of plantings per hectare. These differ depending on the quality level expected for that AOC.

For example, in Bordeaux, there are 65 AOCs, with widely differing densities, from 10,000 vines per hectare in the high quality Pauillac AOC to 3,000 in the lower quality Entre Deux Mers.

However, it is important to note that these are minimums, vineyard owners can plant higher densities if they want to make higher quality wines.

How long will new vines take to produce wine? 

Although vines start to produce grapes from their first year, for example these vines, being planted in July 2022, will produce grapes on new shoots that grow in summer 2023. These first-year grapes are no use for making wine, not wine you would want to drink anyway.

It takes three years before you get grapes from which you can make anything close to decent wine.

A key thing to remember with grapes for making wine is that they grow in spring from buds retained from the previous year, so they grow on one-year old shoots.

Over the winter, vines are pruned to remove most of the shoots grown the previous summer, leaving one or two suitable shoots for the grapes to grow on the following summer. Therefore, if you plant new vines in 2022 it is summer 2024 before you could have grapes growing on one-year old shoots.

Grapes can form on new shoots created in the year (called lateral shoots) but these grapes are of lower quality and are usually removed and not used for winemaking. 

So, by 2024 we should have grapes (two years after planting) that have grown on one-year old shoots and therefore, in theory should be suitable for winemaking.

However, vines need a bit longer to bed-in. For roots to establish and for the grapes to be of sufficient quality to warrant making wine. The standard across the wine-making world is three years from planting before you have grapes for wine. 

Quality will be lower in these early years, if you have planted them in the right place and tended them well, they can start to come into their own from the fifth year and can last for 30 to 40 years.

Exceptional vines continue to improve with age and produce wines of exceptional quality and are marketed as such, worth trying if you spot “Old Vine” on a label.

Cheers!

Janne Hallinan

@how2enjoywine