On 11 Jul, 13:06, "Paul E. Lehmann" > wrote:
> michael wrote:
> > I have absorbed though not completely understood
> > all of the advice I have received on this group
> > recently.This week (first week in July in
> > England) I have been hedging my 35 vines for the
> > first time this summer.They are on Double Guyot
> > which involves renewal cane pruning.My main
> > query in my recent mails is how to prevent the
> > mass of growth which develops in mid summer,and
> > so preventing air and spray get thoroughly to
> > all parts of the vines.Just to be sure what I
> > mean,I will try to explain clearly and without
> > diagrams what the problem is. 1)The Double Guyot
> > system,widely used in England and
> > Europe,involves removing most of the vines
> > growth each winter,and leave two horizontal rods
> > which start near the top of the old 15" high
> > thick base.These rods are each about 2 foot long
> > and stretch right and left along wires.From each
> > rod about 7-8 buds are selected-some buds are
> > double or triple and I reduce these to a single
> > bud. In early summer these buds break and
> > produce rapidly growing vertical canes.Most
> > canes produce flower and fruit around 2 to 2.5
> > feet from the ground.In addition there is
> > vertical growth near the centre which is used
> > for the following year's rods. 2)Each of the
> > vertical canes grows quickly to the top wire at
> > 5.5 feet,when they are 'hedged'.Along these
> > vertical canes,buds and leaves are produced at
> > about 6"-8" intervals,and in the angle between
> > the buds/leaves and the cane,sideshoots appear
> > at 45 degrees.It is these sideshoots that cause
> > the problem of growth.I am never sure whether to
> > remove them initially in June when it is easy,or
> > only remove the badly placed ones later when
> > they will inhibit grape development. 3)It does
> > not seem clear to me whether these sideshoots
> > have a clear function, either to support grape
> > development or feed next years buds on the
> > vertical canes chosen for next years horizontal
> > rods. 4)On this latter point,I have noticed that
> > my newly planted vines are much more fruitful in
> > their early years than later.Could this be
> > because when initially producing the first
> > rod,one is encouraged to remove sideshoots from
> > its vertical growth-it is then bent horizontally
> > to produce a first (single Guyot) crop.This
> > strongly suggests to me that sideshoots are not
> > required to support the next years fruit bud
> > development. 5)So my current thoughts are to
> > remove sideshoots from the renewal vertical
> > canes,but keep them on the vertical canes
> > carrying this years fruit.I have seen in one
> > article that these sideshoots should be pruned
> > to two leaves,which might be a compromise.
>
> > I hope I have described the problem more clearly
> > than before,and I am surprised that this massive
> > growth problem created by these sideshoots is
> > not discussed more in the literature.
> > Cheers,Michael
>
> Michael, I have read in the literature is the
> number of leafs required to ripen fruit. It seems
> that shoots of approximately 4 feet in length are
> the ideal length and the ideal number of leaves.
> (California trials, I believe) Longer shoots
> actually seem to be detrimental to fruit quality
> according to an article I read. *But, like you
> said, I do not know if the leaf count included
> the leafs in the laterals. *If my laterals are
> causing shading or a dense canopy, I remove them,
> otherwise I leave them. *There is often articles
> about research in this area and more about
> viticulture research in general in the
> publication "Practical Winery & Vineyard" *Their
> website iswww.practicalwinery.com
>
> Here is one from this link that specifically
> addresses the question and it seems that it
> "depends" on several factors including the vigor
> of your vines, canopy shading etc etc:
>
> http://www.practicalwinery.com/sepoct01p5.htm- Hide quoted text -
>
> - Show quoted text -
Hi Paul,
Thanks for that.The last pointer you gave seems
particularly useful,and I will study it carefully.It seems as though
laterals are important to help ripening of the fruit,but a balance
must be made if one gets hopeslessly congested near ripening
times.Cheers,michael