BLUE FOCUS NEWSLETTER- April 2026
Hello everyone,
As the 2026 wild blueberry season continues to unfold,
growers are moving from early spring conditions into a period of increasing
field activity and more rapid crop development. This issue brings together key
updates to support timely decision-making, including weather trends, soil and
drought conditions, crop development indicators, and practical management
considerations for both sprout-year and crop-year fields.
We hope you find this information useful as you
prepare for the weeks ahead in the 2026 season.
Wishing you an enjoyable, productive, and successful 2026 wild blueberry production season!
Hugh Lyu
Wild Blueberry Specialist, Perennia
hlyu@perennia.ca; 902-890-0472.
April 30, 2026
Table of Contents:
Weather Update
Crop Stage and Growing Degree Days (GDDs) Update
Upcoming Management Activities
Upcoming Events
Weather Update
In this section, we provide regular weather information
updates to help growers track seasonal progress and support management
decisions. Key parameters reviewed include seasonal crop development indicators
such as growing degree days (GDDs) and heat accumulation, soil temperature
trends, and current drought conditions.
1. Kentville Weather Update
The Kentville Research Weather Station maintains one of the
longest and most consistent weather records in Nova Scotia and continues to
provide an early snapshot of growing season conditions across the province.
These data are particularly valuable for monitoring degree-day accumulation and
soil temperature trends at the start of the season.
The graph below illustrates heating degree-day accumulations
for plant development (base 5 °C) and insect development (base 10 °C) from
March 1 to April 27 across the past 17 seasons. These data are compiled by
Agriculture and Agri-Food Canada (AAFC) Plant Physiology and Perennia’s Tree
Fruit Specialist, Michelle Cortens. We sincerely appreciate their continued
collaboration and annual sharing of this information.
As shown in Figure 1, degree-day accumulation for the
current season remains below the levels observed in 2024 and 2025, as well as
below the provincial five-year average. This trend aligns with field
observations of slower crop development in wild blueberry production areas.
Weather conditions throughout April have been typical of a
Maritime spring, characterized by alternating periods of mild temperatures
followed by cooler, late-winter-like conditions. These fluctuations have
moderated heat accumulation and contribute to the slower seasonal progression
observed to date.
Figure 1. Degree Days
from March 1 to April 27, 2026.
From a soil temperature perspective—another key factor
influencing early spring crop development—current observations indicate soil
temperatures are higher than both the 10-year average and those recorded in
April 2025. This trend is largely attributed to reduced soil moisture and drier
ground conditions resulting from last year’s significant drought. An update on
current drought conditions and regional monitoring indicators is provided in
the following section.
Figure 2. Soil
temperatures from Kentville Research Weather Station.
2. Current Drought Conditions
The most recent Canadian Drought Monitor update (March 31,
2026) indicates broad improvements in drought conditions across the Atlantic
Region, largely driven by above-normal precipitation received during March.
These moisture inputs have helped replenish surface soil moisture and improve
short-term growing conditions following the widespread dryness experienced last
season.
According to the March
2026 Drought Assessment, “Nova Scotia received near to above normal
precipitation (85% to 200% of normal) improving soil moisture and surface water
availability, which led to a reduction in Abnormally Dry (D0) and Moderate
Drought (D1) across central and northern regions and the removal of Severe
Drought (D2) areas in the south.”
Figure 3. Canadian
Drought Monitor, Conditions as of March 31, 2026.
3. Seasonal Forecast (May–July 2026)
We also provide a seasonal outlook highlighting
probabilistic temperature and precipitation forecasts for the upcoming
three-month period (May, June, and July 2026). These forecasts offer a broad
indication of expected weather trends rather than precise short-term
predictions.
Compared with the previous seasonal outlook issued earlier
this spring, current forecasts suggest an increased probability of above-normal
temperatures and above-normal precipitation across Nova Scotia during the
upcoming wild blueberry growing season.
Figure 4. Temperature
and Precipitation Probabilistic Forecasts, Produced on April 30, 2026.
Crop Stage and Growing Degree Days (GDDs) Update
Wild blueberry fields will soon begin transitioning into a
period of rapid crop development. Close monitoring and accurate identification
of crop growth stages are essential during this time of year, as many field
management activities—including pest management, fertilizer applications, and
other cultural practices—are timed according to crop stage to ensure crop
safety and maximize effectiveness.
In this section, we share crop development resources and
practical methods growers can use to track Growing Degree Day (GDD)
accumulation throughout the upcoming blueberry management season.
1. Wild Blueberry Phenology (Crop Stages)
Under the wild blueberry two-year production cycle, fields
are classified as either sprout year or crop year. Each field type follows a
distinct sequence of growth stages and management priorities.
The figures below provide a visual overview of the key
developmental stages observed in both sprout-year and crop-year fields. These
stage descriptions serve as a practical reference to support field scouting,
management timing, and communication among growers and advisors throughout the
season.
Figure
5. Key growth stages in wild blueberry sprout and crop fields.
Resource
and photo credit: University of Maine, University of Maine Cooperative
Extension.
We also encourage growers to make use of locally developed
resources and online tools to better understand wild blueberry crop stages and
Growing Degree Day (GDD) accumulation throughout the season:
·
Understanding Growing Degree Days in Wild
Blueberry Production
This factsheet explains how GDDs are calculated and how they
relate to wild blueberry growth and management timing.
·
Perennia’s Wild Blueberry Blog — Growing
Degree Days (Phenology Tracker)
https://www.novascotiawildblueberryblog.com/p/phenology-tracker.html
This webpage provides regular seasonal GDD updates from
selected weather stations across Nova Scotia from April 1 through October 31.
The page also includes an introductory section describing wild blueberry crop
development in Nova Scotia and an overview of available GDD models used to
support management decisions.
These tools can assist growers in tracking seasonal progress
and improving the timing of field operations throughout the production year.
2. How to Obtain GDD Totals for the 2026 Season
There are several practical ways growers can obtain Growing
Degree Day (GDD) totals to estimate crop development stages in their wild
blueberry fields.
·
Farm Data Tools — GDD Calculator
https://www.docs.perennia.ca/farmDataTools/growingDegreeDays
The GDD Calculator allows growers to calculate degree-day
accumulation at any time using available weather stations across the region.
This tool provides flexibility for selecting stations closest to individual
production areas.
For the Nova Scotia wild blueberry GDD model, growers should
use the following settings:
Start date: April 1
Base temperature: 0 °C
·
Perennia Wild Blueberry Extension Program —
Seasonal GDD Updates
https://www.novascotiawildblueberryblog.com/p/phenology-tracker.html
Each season, the Perennia Wild Blueberry Extension Program
reports seasonal GDD accumulation from selected wild blueberry weather stations
across the province. Updates begin on April 1 and continue throughout the
growing season, providing a convenient reference for tracking regional crop
development trends.
Monitoring GDD accumulation alongside regular field scouting
will help improve management timing and support informed decision-making
throughout the 2026 production season.
3. GDD Total in Wild Blueberry Fields
During the 2026 growing season, we plan to provide periodic
Growing Degree Day (GDD) updates using selected wild blueberry weather stations
across the province. Growers will see these values updated regularly on the Wild
Blueberry Blog’s GDD tracking page and shared during upcoming virtual
grower meetings.
As the season progresses into the critical blight management
and pollination periods, producers can expect more frequent updates on GDD
accumulation, crop development stages, and blight infection risk. Timely
information will be communicated through the Blight
Line and seasonal production alerts to support informed management
decisions.
Figure 6. Selected
Wild Blueberry Weather Stations for GDD Updates in 2026.
A summary of selected wild blueberry weather stations and
their accumulated Growing Degree Day (GDD) totals from April 1 to April 29 is
presented below (Figure 7).
Figure 7. GDD Total
(April 1-29, 2026)
Upcoming Management Activities
Looking ahead to May, wild blueberry crop development is
expected to accelerate, marking the transition into a period of increased field
activity.
In the following section, we outline key management
practices for both sprout-year and crop-year fields, highlighting priority
operations aligned with current crop stages to support effective and timely
field management.
Sprout Vegetative Fields
Plant Emergence, GDDs, and Sprout Field Management
The status of plant emergence in sprout-year fields is a
critical factor in determining the timing of key field operations (Figure 8),
including herbicide and fertilizer applications. Proper timing of these
activities is essential to ensure crop safety and optimize treatment
effectiveness.
The following recommendations are provided to support grower
decision-making and planning. However, growers are strongly advised to confirm
field conditions locally before implementing any management actions, as crop
development can vary by site and field conditions.
Figure 8. Wild
Blueberry Plant Emergence
• Wild
blueberry plant emergence typically begins at approximately 213 GDD (base 0
°C). Growers are generally encouraged to apply pre-emergence herbicides between
150 and 200 GDD to ensure optimal timing.
Most pre-emergence herbicides, including products such as
Chikara, Ignite, Spartan, and Velpar, should be applied prior to crop emergence
or when emergence is minimal (approximately 5–10%). This timing helps improve
weed control efficacy while reducing the risk of crop injury and ensuring
overall application safety.
Crop Fruiting Fields
Blight Risk and Fruit Bud Development (F2 Stage)
The blight season is approaching rapidly in crop fields.
Careful monitoring of fruit bud development—particularly the F2 stage—and local
weather conditions is essential for timely and effective planning of fungicide
applications.
Fruit bud development at the F2 stage (Figure 9) is a key
indicator used in Monilinia blight management decisions. Industry guidelines
indicate that blueberry fruit buds become susceptible to blight infection when
F2 development exceeds approximately 40%. As a result, fungicide applications
are recommended to protect the crop during the primary susceptible window,
generally from 40% to 80% F2. Timely applications during this period are
critical to achieving effective disease suppression and maintaining crop health
under conducive environmental conditions.
Figure
9. Wild Blueberry Fruit Bud F2 Stage
Upcoming Events
1.
Wild Blueberry Virtual Grower Meetings-
May
Event page and registration link: https://www.perennia.ca/eventer/wild-blueberries-virtual-grower-meetings-2026/edate/2026-04-08/.
o
May 6, 2026. 8:30 AM- 9:30 AM
o
May 20, 2026. 8:30 AM- 9:30 AM
Special Topic and Guest Speaker
We are pleased to announce that Dr. Lily Calderwood has
kindly agreed to join our May 20 virtual meeting as a guest
speaker to present on mulching practices in wild blueberry fields. Dr.
Calderwood is the Extension Wild Blueberry Specialist and Associate Professor
of Horticulture at the University of Maine.
Her presentation will provide an overview of mulching
options for wild blueberry production, including suitable mulch materials,
recommended application depth and timing, and the potential benefits of
mulching for weed suppression, soil moisture conservation, and overall plant
health. We look forward to your participation in this session.
Mulching in Wild
Blueberry Fields. Photo Credit: University of Maine Cooperative Extension.
2.
WBPANS Field Day- June 24, 2026, Upper Onslow,
NS.
Save the Date! This year’s wild
blueberry field day will be at the River Breeze Farm, 699 Onslow Road, Upper
Onslow, NS.
