Thanks for all the info, a very interesting thread. However I’ve read it three times and am still confused, particularly in regard to optimum density vs soil vigor.
On higher vigor soil is it best to plant at higher densities so the roots are in competition for the available nourishment, or is it best to plant at lower densities to reduce canopy management issues?
Similarly on very low vigor soil is it best to plant at very high densities in order to achieve economic fruit yields?
Hello Peter,
Great questions. I think high-density is best used on low-vigor sites for optimum wine quality - not for economic purposes. At least -our choice was completely about wine quality- I can think of easier ways of making money than growing too many grapes.
On higher vigor soil you should plant tomatoes ![[wink.gif]](/uploads/db3686/original/2X/0/04707e6a7bbb03e0153e349d8a9270d30e1e9525.gif "wink"){kind=small}
-or you need a greater distance between the vines to allow the room for more buds to balance the vines. Higher density spacing does not reduce vigor- soil, rootstock, cover crops etc., can reduce vigor.
Hope that helps.
"On higher vigor soil you should plant tomatoes -or you need a greater distance between the vines to allow the room for more buds to balance the vines. Higher density spacing does not reduce vigor- soil, rootstock, cover crops etc., can reduce vigor. "
Yes!! I love the tomatoes point 
Regarding vigor, I think that density increase reduce the vigor. I agree that the other parameters (rootstock, cover crops, and I would addition fertilisation) are more important, but if you don’t change anything but just the density, you will reduce the vigor. But then, you will arrive to an other problem. Even with less vigor than with less density, it will still be more vigourous than on poor soils, and so you will have much leaves and no room for it because the vines will be too close. So… stop fertilisation, ad cover crops etc will be the solution on richer soils.
Florian
Actually, with tomatoes a high nitrogen level will cause them to produce more foliage at the expense of fruit set.
[quote="Wes BartonYou might be interested in “Last Call - The Rise and Fall of Prohibition” by Daniel Okrent.[/quote]
Thanks for the suggestion. Blood and Wine: Unauthorized Story of the Gallo Wine Empire (1993) is also good on the adaptation of the winemakers to prohibition. In the Gallo family’s case, they branded their grapes and shipped them to Italian home winemakers in the East. As I recall, they even had railroad reefers (iced cars) with their name on the side. Oh, and they also continued to make wine illicitly.
One of many examples of low soil vigor with low vine density, which includes no cover crop and head (basket) pruning, also important. Water is a factor in spacing: high density spacing absorbs water faster (soil profile notwithstanding), mitigates excessive growth (vines stop vegetal growth earlier), maintaining a relatively open vine canopy, reducing mildew/mold pressure. High density spacing is desirable in regions where significant rainfall occurs during the growing season. Yes, low vigor soils or ones with good drainage are beneficial, too.
Up to a point.
But if the rainfall is greater than “significant”, and if other factors (primarily soil depth and fertility) promote high vigor, then high density plantings may be a recipe for disaster, yielding extremely vigorous growth, heavy shading, and decreasing bud fruitfulness.
As other have said, it all depends…
In the northeast US the old school view for vigorous sites(high water retention and high nitrogen levels) was to go less dense planting to give the vine room to spread. This is primarily an in-row density view but it somehow included a larger than needed between row distance. However, one can deal with vigorous sites through a number of strategies(cover cropping, drainage, hedging, etc) including increasing vine plant density. For a grape farmer that has sandy loam, like myself, it is a different situation than a farmer with heavy clay soils that retain more water at field capacity among other soil properties. My/our selection of vine density of 4 x 7 was related to many things already said including reducing water vigor, increasing per acre yield(linear canopy length), limited farm size, and others. One of the “others” is with less fruit per plant one has a better chance to synchronize the ripening for harvest if not overcropping. I think past shared experiences with increasingly better research studies have shown that we can deal with most vigorous sites when planting at higher densities. I don’t believe higher density precludes having healthy balanced grapevines…Gary
[/quote]You might be interested in “Last Call - The Rise and Fall of Prohibition” by Daniel Okrent.
Yes, wineries only survived if they were able to sell sacramental wine or “medical wine”, sold by prescription through pharmacies. An important note that Paul Draper has brought up is the knowledge base was devastated by that 18 year gap. The immigrants who came over in the 19th century and made wine did so as they had back in the European wine regions they came from, with generations long family knowledge. After Repeal, those families had largely moved on to other things. The next wave of winemakers were virgins, subjected to newfangled modern winemaking equipment and techniques developed in France and pushed by UC Davis. This was the birth of “industrial wine”.
On the vineyard side, a lot of the better sites were torn up. Quality wasn’t important. The need was for thick skinned varieties that could be shipped by rail nation-wide, and scale. I would guess the new growers were farmers filling a need and following the broker’s advise on how to attain the best yield. So, I’m sure the vast majority of knowledge was erased here, too, with some new bad habits being carried forward.[/quote]
Thank you Wes- I will check out the book. I totally agree with your points!
A few years old -short video on spacing
Great video, very interresting! Thanks for posting this! I agree with the style changing, and also with the ageability difference! I just miss the “under the ground” part: roots etc.
I need to visit your winery!
Florian