Rain, Rain Go Away!

Friday, July 19, 2024

Happy Friday Dear Readers!

I hope this rain has not put a damper on your spirits.

For this post, I will continue to focus on disease prevention as precipitation will very likely continue into next week.

Diseases:

Please be vigilant and stay on the look-out for Downy and Powdery mildew as the inoculum would still be present from last year. If you have had issues with Black Rot in the past, please ensure that your spray regime is tight as it will take time to decrease the inoculum to less severe levels. Pesticide groups 3 and 9 are effective for Black Rot control; group 7 is weak on Black Rot in high pressure situations like what we are currently experiencing.

With so much rain over the last two weeks, please ensure that your spray windows are tightened- the 8-10 day interval for systemics and 5-7 for protectants can be narrowed as 200mm of rain will have had a negative effect on product efficacy.

In about 10 days or so, you should also be considering botrytis sprays – just before bunch closure- to ensure the clusters are protected from inside the cluster and out. With the onset of ripening come wasps and other pests, so sour rot may also become an issue.

As always, please consult the online spray guide tool for products and rates.

As we are dealing with several diseases, my next installment will explain the life cycles of these blights, so to give a better understanding as to why we utilize certain practices at particular times of the year.

Growth Stages and Vineyard Practices:

In terms of growth stages- we are getting close to the lag phase- the ideal time for cluster thinning and leaf removal. To save time, if able, mechanically thin initially, then at a later date, go back in by hand and remove more if needed. Leaf removal will help with air movement in the canopy and allows your clusters the sunlight they need to ripen.

Again, to ensure a consistent crop load year after year, it is advisable not to over-crop the vines. Remember that 15-20 leaves are necessary to ripen one cluster on one shoot.  

Pre-Harvest Considerations:

Hedging:

·       Tucking, hedging and leaf removal are to be done now. Please avoid hedging 30 days prior to harvest- the canopy is needed to ripen the clusters.

Communication:

·       Contact your grape buyer and verify their guideline on the date of the last spray. The products may indicate three weeks, however, your requirements may be specified otherwise.

Please note:

As harvest time approaches, I may be putting out more than one weekly post to keep themes more concise, timely and not overwhelming.

Please see below for growth stages, GDD and Precipitation as provided by Jeff Franklin at the Kentville Research Station.

Month

25-Year Average

(mm)

Current Year

(mm)

April

81.5

54.0

May

74.0

29.8

June

95.5

83.0

July

81.3

        201.7 **

August

94.5

 

September

104.1

 

October

115.8

 

*Up to July 18, 2024

Growing degree days, base of 10 °C starting on April 1

Current Year

10-Year Average

562.5

455.8

*Up to July 18, 2024

Date of Assessment

Marquette

L’Acadie blanc

New York Muscat

18-July

50% Berries at pea size, 50% Berry touch

75% Pea Size, 25% Berry touch

Berry touch

 

  

                   Chardonnay                             L'Acadie                               Marquette
                                                                                   
 
                                     Frontenac Gris                  Pinot Noir                          New York Muscat                                                                                                                                 

 As is visible above, in the valley, Marquette and Frontenac Gris are close to full berry touch, L’Acadie is at pea size to berry touch, Pinot Noir and Chardonnay are at pea size and New York Muscat is at about 8-10mm size. Remember that loose cluster varieties may not see the “berry touch” phase.

These photos were taken on the 17th July 2024.

In terms of pests, phylloxera and Erineum Mite are prevalent- Japanese Beatle as well but to a lesser extent.

Again, please consult the online Pest Management guide and follow label directions for any sprays you may use. 

Lastly,

Our Cover Crop Information Session is on the 24th July 5-7:30pm. To register, please use the link below:

https://www.perennia.ca/eventer/growing-between-the-vines-cover-crops-in-vineyards-panel-discussion/edate/2024-07-24/

Thank you all for your time this week, and I look forward to seeing many of you next Wednesday.

Cheers!

Katarina

Viticulture Specialist

Perennia Food and Agriculture
Email kvucic@perennia.ca
Office 902-678-7722

Cell 902-599-1390

www.perennia.ca

 



 

 

Precipitation Warning and Canopy Practices

Monday, July 15, 2024

 

 Greetings Dear Growers,

Apologies for the late posting; I was away for a conference last week.

With rainfall totaling over 200 mm in some areas this past week, many of you had questions about spray products and frequency. Just a reminder that it is very unlikely that any effective fungicide residue remains on the vines after that significant rainfall; keeping on top of disease pressure is paramount.

As we should be receiving more rain this week, here are some guidelines and recommendations provided by Dr. Kevin Ker:

Please remember: It is highly encouraged to have re-applied fungicides in advance of upcoming rain events to maintain high levels of disease protection.


Water Use:

Be sure you are also using enough water to thoroughly cover all susceptible tissues. With rapidly expanding and near-full canopies now present, you should be using at least 500 L of water per ha or more to provide proper spray coverage. At vigorous locations with big canopies, 750 L of water per hectare is preferred.

 

Water is the primary carrier of pesticides from the spray tank to the plant tissues and should be continually adjusted to match the canopy development at your farm. If you are identifying disease infections in hidden/hard to reach areas of the canopy or on the backside of clusters, you are not achieving optimal spray coverage and should consider increasing your water output.

 

Disease pressure:  

Berries are highly susceptible to infections from Downy Mildew, Powdery Mildew and Black Rot until veraison is well underway. Green tissues such as leaves, petioles, shoots and rachis tissues are also highly susceptible to mildew and black rot infections, so it is important to recover following wash-off rain events, keep tight spray intervals of 7-9 days and continue using good locally systemic fungicides where possible.


Vineyard Practices:  

Carry on with your fruit zone leaf removal activities as this will open the fruit zone allowing for better air flow and spray penetration around berries. It is advised to remove basal /fruit zone leaves that are layered in stages on white cultivars, so they have time to adapt to the new conditions.

Risks Associated with excessive leaf removal:

If you are too aggressive in leaf removal around clusters, leaving the fruit fully exposed in white cultivars, you risk burning or baking the newly exposed berries. It is common to remove leaves on the east side of the row first then follow-up by removing leaves on the west side 7-10 days later. You can be more aggressive in your first leaf removal pass in red cultivars, removing leaves from both sides of the row.


As previously mentioned by Dr. Deb Moreau, sightings of Japanese Beetle and

Phylloxera are increasingly prevalent.

 

                               Japanese Beetle Leaf Damage               Phylloxera Damage

If you have previously used Movento for phylloxera control, please consult the Perennia online pest tool to evaluate other products if you need follow up sprays. Read and follow the label rates.

 

Below, please see the Precipitation, GDD and Phenological Observations, provided by the Kentville Research Station up to July 11th, 2024.

 Table 1: GDD:                                                                                   

Growing degree days, base of 10 °C starting on April 1

Current Year

10-Year Average

462.5

379.0

 

 

 

 

Table 2: Precipitation:  

Month

25-Year Average

(mm)

Current Year

(mm)

April

81.5

54.0

May

74.0

29.8

June

95.5

83.0

July

81.3

        99.8 **

August

94.5

 

September

104.1

 

October

115.8

 

Table 3. Phenological stages of three varieties . Bud break for all three varieties was between May 18 and May 20, 2024.

Date of Assessment

Marquette

L’Acadie blanc

New York Muscat

11-July

BERRIES PEA SIZE

BERRIES PEPPER CORN TO PEA SIZE

BERRIES PEPPER CORN TO PEA SIZE

 

Our observations: Date of Assessment: 11 July 2024.

  •        Frontenac

Berries pea-size

  •         Pinot Noir

Setting: Young berries growing; bunches are at right angles to the stem.

  •         Chardonnay

Setting; some berries >2mm


Lastly, a gentle reminder about the Cover cropping info session next Wednesday at 5:30pm at Benjamin Bridge winery.

 

Thank you all for your time this week, and looking forward to seeing many of you at the info session next week.

Cheers!

Katarina Vucic

Viticulture Specialist
Perennia Food and Agriculture
Email kvucic@perennia.ca
Office 902-678-7722

Cell 902-599-1390

 

www.perennia.ca