We have a little bit more to cover in this post as we are
facing more production challenges, getting further into the season. Some key
words you will hear a lot in the next few weeks: Frosts, Botrytis blossom
blight, Pollination, cold damage and disease symptoms (cold damage vs monilinia
blight symptoms vs botrytis blight symptoms).
Frosts!!!
This morning (May 19), we
got frosts in some areas and there are three areas with particularly low
temperatures (below -2 c). Please take a chance to check your crop fields near
those stations/areas I mentioned below.
If you observe any frost damage in your area, please let me know. hlyu@perennia.ca; 900890-0472.
NSW001- Glenholme: -3.1 c
NSW038- Staples Brook:
-2.2 c
NSW037 and NSW038- Belmont:
-3.6 c
NSW060- Blue Mt.: -2.3 c
NSW061- Moose River: -3.6
c
I don’t think fields in
those areas are in bloom yet. Most of the fields should be around 80-90% F2 and
in a tight cluster stage.
Chaplin (NSW071): -3.2 c
Growing Degree
Days (GDD) Summary and Plant Development Updates
Figure 1. GDD Summary, May 18, 2023
Sprout fields:
Sprout fields in Cape Breton still
have a few days for growers to safely apply pre-emergence herbicides. For all
of the other fields in NS, the safe window to apply spring herbicides was passed.
If you still want to apply pre-emergence herbicides, please contact me and we
can look at individual cases.
Crop fields:
Here is a picture of the crop (bud
and bloom) development stage in different regions.
1.
Southshore counties and
early fields (those stations with GDD above 300) in Cumberland: early flower
and beginning of bloom (about 5-10%).
2.
Hants, HRM (Dean and
Musquoboit area), Truro and Debert area: in a tight cluster stage with some
early flowers
3.
Rest of Cumberland and Colchester:
70-80% F2 and tight cluster stage
4.
Pictou and Gusyborough:
60-70% F2 and tight cluster stage
5.
Antigonish and Cape
Breton: passed 40-50% F2
Monilina blight infection risk is
still something we should watch very closely since we are still in a critical time.
After this long weekend, I would expect that the infection risk will be low to
mainland fields but for growers in Cape Breton, you still have another 2 weeks
to be out of this year’s monilinia worrying.
Some very early fields will get into
20-30% bloom after this weekend and for most fields, it is looking like we will
have another early bloom season. In 2022, the earliest average week for growers
to put out bees was the last week of May.
As bloom starts, botrytis blossom blight
infection risk increases. I will start to talk about this disease next week.
Frost Damage?
Disease Infection? Monilinia VS Botrytis?
Many growers are wondering how to tell the differences
between frost damage and disease infection on leaves and flowers. The UMaine
Wild Blueberry Extension team produced a very nice factsheet and this is a good
one to print and keep handy.
