UGA Extension Viticulture Blog

Harvest update / post-Irma harvest considerations

Dear all:

First and most importantly: I know many of our blog subscribers were in Irma territory. I sincerely hope everyone that was in the path of Hurricane Irma is safe out there.

Harvest update:

I have seen and heard about some good things out there despite this tough, wet year.

I have also seen some ugly things.

The good: Hybrids.  These “workhorses” make it through the perennial ups and downs of east coast viticulture. It’s really as simple as that.  Chambourcin, Traminette, Vidal blanc, and Chardonel have fared well.  On Saturday, I was in a Chambourcin vineyard that looked like it was grown LAST year – meaning it literally did not have one spot of disease or rot in it. Further, it makes nice wine with several vinification options – red, rose, port, etc.  I would encourage vinifera growers who are looking to round out their portfolio to consider planting these varieties.  On this note, the PD-tolerant hybrids (Lenoir, Villard blanc, Norton) have fared reasonably well, but not without some sour rot – especially in Blanc du Bois and Lenoir, and to a much lesser extent in Villard blanc and Norton.  Whites. Some whites were harvested weeks ago for stainless and sparkling wine production.  While these still had some rot issues, they were much less disease-infested than those that have been harvested in the last couple weeks and/or remain to be harvested (see pictures, below).  Varieties like Petit manseng are relatively disease tolerant, have thick skins, and loose clusters.  Petit manseng has greater potential to “hang” compared to tight-clustered, thin-skinned whites (i.e. Chardonnay, Vidal blanc).  Muscadines. Bronzes usually have some ripe rot issues, and this year has been no different.  However, I have heard good fruit chemistry reports from the major Carlos and Noble muscadine growers this year.

The bad: Diseases.  It has been a rot and downy mildew kind-of-year, and Irma has not helped.  Pretty much every vineyard I have stepped foot in has had downy mildew in the canopies and/or sour rot and botrytis on their fruit.  This has not been due to lack of management, but rather an attempt to spray and manage between long and frequent bouts of rain.  Mix the past- and recently-experienced rainfall with the increasing Brix levels and the forecasted warmer weather, and botrytis and sour rot infestation will ensue in short order – especially if berries start splitting.  Last, due in no small part to the mild winters we have had recently, I have seen Pierce’s Disease (PD) in almost every vineyard I have been in this year – and even observed PD at the higher altitudes in northern Georgia.  I won’t go into detail on this as Dr. Phil Brannen, UGA Fruit Pathology Specialist, will be posting about identifying and managing vineyard PD sometime in the next couple of days.

Sour rot in Chardonnay that was harvested three weeks ago (bottom) and arrested botrytis and sour rot in Chardonnay that was harvested a couple days ago (top).

post-Irma harvest considerations:

There may be several ways to look at the post-Irma harvest situation.  I’ll break it down into two possible approaches to harvest – for simplicity, if nothing else.

1. “It has been a tough year and the fruit isn’t ripe, so I’m going to continue to hang the fruit for better quality.”

2. “It has been a tough year and the fruit isn’t ripe, so I’m going to harvest the fruit as soon as possible and not risk losing crop due to rot.”

Approach 1. may be hopeful for this year.  Approach 2. may be conservative, but likely a bit more realistic for this year.

Approaches 1. and 2. are both absolutely correct in that it “has been a tough year,” and this has been touched on above.  Approach 2. will likely produce light-bodied, acid-forward wines.  However, the “quality” that is aimed for in approach 1. might not necessarily be attained this year.  Who knows if the weather will be cooperative? Further, it is difficult to ripen fruit that is rotting apart, and canopies may be less than efficient due to wind damage and downy mildew incidence/severity.  Both of the above approaches also use two subjective terms – “ripe” and “quality”.  What is “ripe” fruit?  What is “quality” fruit?  Is “ripe” fruit that which is greater than 22 Brix with varietal character? Is “quality” fruit that which is 19 Brix and free from rot?  I suppose these terms truly are subjective and depend on several factors, and the winemaking goal is one of those factors.  Eastern US grape and wine industry members often experience highly-contrasting weather patterns in consecutive vintages.  As such, we are often faced with changing our harvest and winemaking expectations due to weather – a problem our western US counterparts might not appreciate as much as we do.

Take home: Remember – it is THIS year, which, unfortunately, is a polar opposite from LAST year.  Since we have already fought several rainy battles, my hunch is that fruit cannot hang as long as we might hope it to.  My advice is to be extremely diligent about monitoring the integrity of your fruit (start right now and monitor daily) and to also be realistic about your expectations of the chemical and sensory attributes of your fruit.  Consider the integrity of your fruit going into Irma.  Consider your specific site and how well it has handled rain in the past.  Is your site well-sloped and sheds rainwater quickly? Is your site flat and vines are sitting in soils that are at their water-holding capacity? When rots start to set in and skins start breaking and slipping, it is time to harvest before things get ugly.

Please contact your county extension agents if you have questions about your vineyard – they are all great assets to your county and can help you make informed decisions.

Hang in there and please monitor your vineyards daily starting right now.

I truly wish everyone the best possible outcome for this ever-challenging vintage.

With sincerity,

Cain