Grape Crop Load Experiment

The right crop load take years to assess and depends on so many variables such as soil, moisture, sunlight, training methods, diurnal temperature fluctuation, humidity, climate (micro and meso), nutrients etc. It really ends up being somewhat of a trial and error that one needs to go through over time.  Crop load is also related to ripening and the general idea is that if a vine is under-cropped it may hasten the ripening process as there is less fruit to ripen. On the other hand over-cropping a variety may slow the ripening process as there is more fruit to ripen. 

This year we conducted an in row trial with Leon Millot to see the how crop load affected grapes chemistry and ripening. We planned to increase the crop load by leaving addition shoots to see if the addition shoots would increase crop load without noticeably affecting the quality of the grapes for this variety.Our noramal amount of shoot is 8 per foot and on part of the row we left 12 per foot. Here are the numbers.

Leon Millot	Brix	PH
8 shoots per foot	22	3.3
12 shoots per foot	19	3.1

We saw that there was virtually no difference in production between the two pruning levels as both produced at approximately 1.5LB per linear foot having on average 2 clusters per shoot. The weight of the clusters on the vines pruned to 8 shoots per foot were averaging about 50 grams in size. We didn’t weight those that came from the vines pruned to 12 shoots per foot. However, the vines pruned to 12 shoots per linear foot in general had smaller and less well filled clusters than the clusters on the vines pruned to 8 shoots per foot. We also note that it took a bit more trellis management to train the shoots on the vines with 12 shoots per foot. It also took longer to harvest the vines with 12 shoots per foot.

The extra shoots did not translate into bigger crop but more work and poorer quality grapes. Bottom line - we won’t be doing that again, but good to know that our crop load is pretty good at 8 shoots per foot.

Also important to note is that the shoots on the vines cropped to 12 shoots per foot were generally shorter and as such won’t be as suited for use in long cane pruning next year – which is the pruning style we have been using for Leon Millot.

Angry Birds Love The Grapes

So we've never had a problem with birds until this year. Most years we don't even see any around before or during harvest but this year we had a "malfunction" with the netting. In late September, just a few days before havest, we had some nasty winds that caused some some of the netting to dislodge from its position.and several row feet of Leon Millot got exposed that we did not see untill harvest.

Pretty much every year it is the wasps that give us grief and the netting keeps them at bay but with the grapes exposed this year it brought the birds in and they pretty much cleaned the exposed grapes off the exposed vines, picking nearly every grape from each cluster. Can see in the photos the clusters stripped on the grapes;

Where the netting was still covering the grapes the birds actually worked their way several feet down the trellis and took those grapes as well or severly damaged the clusters. The amazing part was how bold the bird were during harvest. We strip the nets off the trellis as we go and the birds were comming right in close in the row or sitting on the netting on the next row over squaking - obviously angry that we were taking the grapes they'd been feasting on.

I was surprised that the bulk of the birds were Robins, at least 7 or 8 of them, as Robins don't seem to pack up like that, they seem more solitary birds. There was also a a few dark birds (almost black in colour) bit bigger than a Robin with a tuff of feathers that stands up on its head.

Lesson learned, more dilligent in deploying the nets next year.

Grape Harvest Parameters 2016

So here is the sugar concentrations for the various grape varieties that we harvested from the vineyard this year. A good year for sugars and ripeness in all the varieties relative to our location and after 8 years of data it really shows which are the standouts over time, especially the past 6 years.

The sugar readings are take in the field on harvest day and are a sampling of a few grapes from various clusters at different trellis heights and positions along the row. The sugar reading are measured in Brix and each brix will give approximately 0.56% alcohol to the wine when fermented. So for example a sugar reading of 20 brix would result in wine with alcohol concentration of about 11.2%.

We usually find that what ever reading we get in the field is often 1 brix higher once the grapes have been crushed and pressed and measured by specific gravity in the tank. So for the readings below, add 1 brix.

The table below also records, the bud break in the spring, the approximate time of flowering, the harvest date, and degree days growing (heat accumulation). Here is the table;

Grape Harvest 2016

Grape Harvest 2016

So it has been an interesting year for growing and the weather has been unusual in both that overall it was a warm year with about 1050 degree days growing celcius (+10c) over 150 frost free days and with a really early spring.  For us a really early spring is bud break 3-5 days early and this year we had about 7-10 days early for some varieties. Growth was good at the start and reds and some whites were flowering the first and second week of June in warm dry weather and had good fruit set. Some of the whites on the other hand flowered about a week later in cool wet weather and we had poor fruit set especially on the L’Acadie Blanc. We did experience some limited powdery mildew continuing on into early July and this had a minor affect on fruit set on some varieties as well.

So we picked the grapes on Oct 1^st and we had some decent numbers this year.

Reds                                                 Brix

Marechal Foch                                  20

Leon Millot                                       22

Castel                                                 23

Lucy Kuhlman                                  22

Triompe D’Alsace                             18

Colmar Precoce Noir                       22

Marquette                                         21

St. Croix                16                                                                   

Regent                                               16

Pinot Noir                                         18

Zweigelt                                            16

Marechal Foch (top) and Leon Millot (bottom) photo

Whites

Evangeline                                          22

L’Acadie Blanc                                   21

Petite Milo                                          23

Seyval Blanc                                       22

Ravat 34                                              18

Seigerrebe                                          19

Sovereign Ruby                                  18

Vandal Cliche                                     20

Siegerrebe photo 

Time to Net The Grapes

As of August 26th the grapes are ripening up well and we are still a bit ahead of usual but hardly enough to speak of. With the early spring and slow progression into heat some of the varieties that take longer to ripen budded out quite early. Usually the ground at our location stays quite cool until late April early may and then the varieties start to push buds and they all do so within a few days of each other.  This year there was 7-10 days between the bud break of all the varieties.

All varieties are healthy with no fungal pressure on the fruit.  We had a bit of powdery mildew in early summer on leaves and shoot tips of a few varieites but it did not manifest into the fruit and in fact even the Seigerrebe and Pinot Noir are not experiencing any n noteable problems from it.

The reds are looking really good with Leon Millot, Lucy Kuhlman and Colmar Precoce Noir the furthest ahead and then Marquette just behind. A surprise is the Regent that this year is not far behind the earliest grapes. Its usually one of the latest to ripen but it will be interesting to see how this year works for it but wouldnt use this year as a baseline as the early spring was an anomally.  Pinot Noir is similar in that it seems further ahead compared to the others than what we'd expect in a normal year.  Castel is looking good with long loose clusters and the Foch and Triompe D'Alsase are good.

Marechal foch

Lucy Kuhlman

Pinot Noir

Regent

St. Croix

Triompe D'Alsace

The whites are a different story and as I mentioned in earlier blogs most of them they flowered later than the reds and when they did it was really rainy and cold and the fruit set was not great.  The Ravat 34 and Vandal Cliche were not too bad and then Evangeline and Seyval simiar in fruit set but not great.  The worst was L'Acadie Blanc.  Petite Millot was good in the fruit set but it flowered earlier with the reds.

Siegerrebe

Seyval

Mid Summer Update - Aug 5th

So I took these pictures on August 5th to show how the grapes are coming along.  The reds really are doing quite well so far this year and its because they flowered before the heavy rain hit in mid June.  The whites are not doing as well with Ravat 34 and Petite Milo doing the best of the bunch and L'Acadie and Evangeline equally poor in fruit set this year.  Petite Milo and Ravat 34 did pretty good but again they were flowering earlier with the reds and not during the rains. There were just a few red grapes just starting to show colour on Aug 5th but most were close to bunch closure and as of Aug 12th many more are starting to turn colour on the earliest varieties like Colmar, Castel, and Leon Millot.
Leon Millot Aug 5th

Lucy Kuhlman Aug 5th

 

 Triompe D'Alsace Aug 5th

Hybrid Vine Training

One of the things people ask when they see hybrid vines is what kind of training system are we using.  We actually use a few different types depending on the vine and other variables including the growing style (uprights or sprawling) and the clusters size (production per shoot). So much depends on the growing style of the vine and the shoots per foot that we need to have in order to have a decent crop load.

For instance the L'Acadie Blanc, Ravat 34 and Evangeline all have good sized clusters varrying in size from 120 to 200 grams. So if we take L'Acadie blanc for instance, in order to get about 1-1.5lbs per foot of trellis space you only need 5-6 shoots per trellis foot at 1 cluster per shoot.  The L'Acadie grows straight up like an arrow and is great for positioning the shoots in the wires. So because we only need 5-6 shoot per foot and they grow upright then we use a verticle shoot training system.  Same for the Ravat 34.

On the other hand Leon Millot produces very small clusters of approximately 45-50 grams on average (sometimes 60 grams).  Most shoots have 2 clusters so you get about 100 grams per shoot.  This means you need 6-7 shoots per trellis foot to get 1.5 lbs per foot.  But if you leave only 6 shoots per foot some of the shoots will grow at least 6 -7 feet long so clearly the vine could support the growth of more shoots. As such we crop at about 8 shoots per trellis foot and the growth is quite balanced at 24-26 shoots per meter. The diffference now is that at this density the shoots can become too dense (leaves from one shoot end up shading the leaves from another shoot) so we need to split them up and as such we use a 4 are kniffen style.  But we do this with canes not cordons.

Our 4 arm kniffen style usally has 4-6 canes in total per vine with 2 lower canes wrapped to a 2 foot wire and 2-4 upper canes wrapped to a 3.5 foot wire and vines  are spaced at 5 feet in the row. Ideally this means each vine has about 40 buds each (8 per foot over 5 feet) producing 100grams of grapes (2 x 50 gram clusters per bud). So production of approximately 4000 grams over 5 feet. So thats 800 grams (1.7 lbs) per trellis foot.  We target 1.5 lbs per trellis foot for Leon Millot and this cropping level seems to meet that as sometime you only get 1 cluster per shoot and that brings the per shoot average down. Other vines could crop higher like Triompe D'Alsace, it could have 10-12 buds per foot but would be way to dense on a single canopy - this many buds per foot would have to be configured on some type of divided canopy like a geneva double curtain or lyre trellis style.

The the other factor with this density is that if you position all the shoot upward then they will still crowd each other so with the 4 arm kniffen they are also allowed to spread out into the area between the rows.  Leon Millot (and most hybrids) vines don't grow staright up also so this fits well with their growing habit and even at 8 shoots per foot you will still get crazy long canes so we are always walking the rows and pinching back the shoots when they get up to 15 leaves in length.

One thing to note is that there are lots of documents that will tell you about pruning styles and how many buds per foot to have for certain varieites but less is known for hybrids.  So use these as more like suggestions rather than guidelines especially as you are starting out but understand that you need to figure out whats best for the variety you have in the soil and climate conditions you have and in relation to ripening the fruit within the season you have. You need to grow the vines with different bud counts and training systems over a few years to figure out whats right for your location.

For a few years we experimented with different styles and bud counts in the same row and after two years quickly figured out whats best.  Having said that, we changed things in the past 2 years with irrigation and fertilizer and now that has changed the growth of the vines (more vigor) and as such we have been working on modifying the bud count and the training system as well.

Vineyard Expansion Going Well

So we planted 2100 row feet of Leon Millot vines and Marechal Foch vines in the spring and we planted then quite deep into the ground so that they have more moisture. 

All the vines are doing well and growing but a bit slow to take off as they really didn't get going until recently.  I think planting them so deep slowed their growth but they all look healthy.

Here is a few pictures of the new vines....in the first picture you can see the test vineyard in the background.