In this publication Jeff Franklin is sharing with us the main observations at the beginning of the season until May 31. All this information is coming from Kentville Research Development Centre (KRDC), therefore, difference between locations are possible to be found.
The first table shows the temperature base 5⁰ C and base 10⁰ C from 2018 until 2021 accumulated each year from March 1 until May 31.
At the end of each section, it’s possible to see the average of the last 5 and
10 years respectively.
|
Category |
2018 |
2019 |
2020 |
2021 |
5 year
average |
10
year average |
|
Plant
development (Base 5ºC) |
299.9 |
230.8 |
259.9 |
350.1 |
282.7 |
304.7 |
|
Insect
development (Base 10º) |
127.1 |
66.0 |
109.7 |
140.4 |
110.6 |
126.1 |
Figure 1. Degree day accumulations as of May 31,
2021. 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 is the similar trend observed the last publications (all of them are available in the blog), the degree accumulation shows a high increase compared to the last 3 growing seasons. Based on 10⁰ C, 2021 has 140.4 which is above the average temperature of the last 5 and 10 years with 110.6 and 126.1 respectively. Meanwhile 2018 is quite close with 127.1. It’s important to remind that plants can develop faster under these conditions, thus it’s important to be scouting the vineyard locations to prioritize canopy activities (such as shoot thinning and tucking), spray applications (Powdery Mildew and Downy Mildew) and weed management.
In the following
column graph, it’s possible to see the values from 2004 until 2021 and at the
end you can see the average of the last 5 and 10 years respectively.
Figure 2. Degree day accumulations as of May 31, 2021
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 graph highlights the difference in the last 2 years and shows some similarities of 2021 with 2017 and 2018. However, currently it’s possible to see even higher values than 2017, one of the years with faster growth in the last seasons. According to this graph and continuing with the same trend as the other times, 2010 and especially 2012 presented even higher accumulation of heat units. The higher accumulation of heat units has accelerated the growth of the vines, starting with the bud burst in average on May 14, which is at least 10 days earlier than 2020. In case to continue with this increase of heat units, the grapevine activity will be happening earlier this season, such as bloom and veraison.
Figure 3. Chardonnay growing very fast in the last
couple days.