Jeff Franklin, from AAFC Kentville, is bringing the weather update in terms of temperature. The last couple of weeks we have mentioned the important amount of rain accumulated and July is already welcoming us with some rain. Generally speaking, the hybrids, always depending where in the province are located the vineyards, are almost done with bloom, with only a couple of exceptions are finishing the process. On the other hand, vinifera varieties, which are usually behind the hybrids, are still in progress and the latest varieties are blooming these days.
The first table shows the temperature base 5⁰ C and 10⁰ C from 2019 until 2022 accumulated from March 1 until July 4. At the end
of each section, it’s possible to see the average of the last 5 and 10 years
respectively.
|
Category |
2019 |
2020 |
2021 |
2022 |
5 year average |
10 year average |
|
Plant development
(Base 5ºC) |
600.0 |
701.9 |
794.0 |
739.5 |
702.7 |
708.5 |
|
Insect development
(Base 10º) |
271.2 |
389.6 |
426.7 |
376.9 |
365.6 |
368.0 |
Figure 1. Degree day accumulations as of July 4, 2022. All data are taken from the Kentville weather
station, based on a start date of March 1, and calculated using the single sine
method.
The last couple of weeks the temperatures have diminished
and it’s possible to see current season with more similarities to the average
of the last 5 and 10 years. 2022 is lower than 2021 base 10⁰ C, this difference has been
increasing the last couple of weeks, with 376.9 for 2022 and 426.7 for 2021 base
10⁰ C. In spite of these differences, phenologically
speaking grapevines have moved as expected for a normal season, impacting
positively hybrids and Vitis vinifera varieties.
In the following
column graph, you can see the values from 2004 until 2021 and at the end the
average of the last 5 and 10 years respectively.
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Figure 2. Degree day accumulations as of July 4, 2022
base 10⁰ C. All data are taken from the Kentville
weather station, based on a start date of March 1, and calculated using the
single sine method.
This week the graph shows similarities of temperature in
2022, with quite similar values to the average of the last 5 and 10 years. Similar
pattern as the previous weeks, in 2021 the temperatures were higher than this year
until July 4. Compared to the other years, 2022 is slightly lower than 2017,
while 2020 and 2022 are quite until this date.
Mentioned the last couple of weeks, even though it sounds repetitive, it’s always good to remember to:
- Scout the most vulnerable varieties at the locations with lower air flow, more humidity, warmer conditions, and the areas where in previous years the diseases have been found.
- Spraying might be necessary in some of the products applied, as contact ones might be washed depending on the amount of precipitation received in the area. Therefore, look at the date of your last application before you decide to move forward.
- Remember to rotate products with the same group to avoid creating disease resistance, pay attention to the re-entry time and keep an eye on the forecast, especially precipitation.
Bloom already started a couple of weeks ago, in some plants
it’s possible to see fruit set and even in some of them the berries are almost
at peppercorn size. If you’re vines are still blooming, it’s the right time for
tissue sampling.
How to proceed with this? Please, look at the following video and fact sheet Grape Tissue Sampling to
have more information on how to proceed.
What are the role of the nutrients? You can read a section
at the Grape
Production guide to get insights about nutrients in grapevines. Please start
from page 33, starting with the Grape Tissue Sampling process.
Figure 3. On the left Frontenac at pea size and on
the right L’Acadie at fruit set.
Figure 4. Chardonnay
at the end of bloom.
Last, but not least, on Thursday July 7 at 6:30 pm
we’ll be hosting the Best Practices session 3!
This session’s agenda will be as follows:
- Alyson Bremner: Services to improve vineyard management
- Jeff Franklin: Weather update
- Francisco Diez: Vineyard activities and emphasis on tissue sampling
- Growers’ discussions: Steve Ells from Ellslea Farm and Danielle Graham from Benjamin Bridge
Registration is required, please see the
following link or
try the hyperlink: https://perennia.zoom.us/webinar/register/WN_bAhevWT4QrqyOC7c8nrs2g
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