2021 Wild Blueberry Phenology Record

Please reference the Maine Wild Blueberry Phenology Guide (PDF), for detailed stage identification.

For mapped locations please return to the Real-Time Wild Blueberry Phenology Tracker. See Development Stages Below.

Locations: Waldoboro Hope Searsport Sedgwick Ellsworth Deblois Montegail Jonesboro Wesley Marion
Week 1  4/12/21 to 4/16/21 Crop Cycle Stages % Winter Kill 28.8% 12.3% 19.2% 8.6% 24.7% 24.4% 35.4% 37.5% 10.7%
% T1 Buds 47% 53% 77% 74% 66% 86% 88% 71%
% T2 Buds 31% 38% 20% 12% 18% 0% 6% 0%
% T3 Buds 6% 1% 0% 0% 0% 0% 0% 0%
% T4 Buds 0% 1% 0% 0% 0% 0% 0% 0%
Week 2 4/19/21 to 4/23/21 Crop Cycle Stages % T1 Buds 35% 53% 64% 82% 55% 98% 67% 85% 79% 73%
% T2 Buds 46% 40% 31% 14% 33% 1% 33% 6% 19% 26%
% T3 Buds 17% 5% 2% 0% 5% 0% 0% 0% 0% 0%
% T4 Buds 0% 0% 0% 0% 0% 0% 0% 0% 0% 0%
Update Locations: Warren Hope Searsport Sedgwick Ellsworth Deblois Montegail Jonesboro Wesley Marion
Week 3 4/26/21 to 4/30/21 Crop Cycle Stages % T1 Buds 22% 35% 14% 35% 7% 92% 53% 84% 56% 69%
% T2 Buds 38% 35% 8% 33% 22% 8% 38% 13% 33% 30%
% T3 Buds 24% 17% 60% 7% 23% 0% 9% 3% 8% 1%
% T4 Buds 6% 10% 16% 20% 36% 0% 1% 0% 0% 0%
% T5 Buds 2% 0% 1% 4% 0% 0% 0% 0% 0% 0%
Week 4 4/26/21 to 4/30/21 Crop Cycle Stages % T1 Buds 2% 11% 4% 12% 0% 66% 5% 12% 4% 26%
% T2 Buds 10% 8% 14% 28% 2% 21% 19% 33% 22% 24%
% T3 Buds 26% 37% 48% 30% 22% 12% 41% 30% 28% 24%
% T4 Buds 15% 21% 21% 12% 22% 1% 29% 19% 27% 16%
% T5 Buds 34% 20% 14% 17% 49% 0% 6% 6% 18% 9%
Prune Cycle Emerged Shoot # 4.7 6.2 1.3 0.2 0.2 4.7 1.5 2.3
Week 5 5/03/21 to 5/07/21 Crop Cycle Stages % T1 Buds 1% 1% 0% 1% 0% 40% 2% 0% 0% 5%
% T2 Buds 0% 1% 0% 1% 0% 29% 10% 11% 9% 13%
% T3 Buds 8% 12% 10% 18% 0% 23% 16% 33% 19% 28%
% T4 Buds 23% 21% 44% 44% 25% 8% 35% 36% 36% 31%
% T5 Buds 52% 59% 46% 21% 74% 0% 34% 19% 35% 22%
Bloom 6% 1% 0% 13% 0% 0% 3% 1% 0% 0%
Prune Cycle Emerged Shoot # 4.3 9.2 14.5 1.0 0.2 1.7 6.0 2.0 3.2
Week 6 5/17/21 to 5/21/21 Crop Cycle Stages % T1 Buds 0% 0% 0% 0% 0% 6% 0% 0% 0% 0%
% T2 Buds 0% 0% 0% 0% 0% 10% 0% 0% 0% 4%
% T3 Buds 0% 0% 0% 0% 0% 39% 2% 3% 2% 10%
% T4 Buds 0% 0% 0% 0% 0% 31% 24% 34% 11% 27%
% T5 Buds 38% 56% 18% 18% 35% 14% 28% 43% 32% 38%
Bloom 51% 41% 80% 0% 59% 0% 46% 20% 54% 22%
Prune Cycle Emerged Shoot # 1.0 0.0 13.7 11.8 8.2 2.5 3.3 6.5 3.3 4.7
Week 7 5/24/21 to 5/28/21 Crop Cycle Stages % T1 Buds 0% 0% 0% 0% 0%
% T2 Buds 0% 0% 0% 0% 0% 7%
% T3 Buds 0% 0% 0% 0% 0%
% T4 Buds 0% 0% 0% 0% 0% 2%
% T5 Buds 0% 0% 0% 0% 0% 52% 1% 11% 8% 19%
Bloom 0% 0% 0% 0% 0% 39% 99% 89% 92% 81%
Closed Flowers 37% 35% 43% 46% 39%
Open Flowers 4% 10% 5% 28% 5% 87% 48% 56% 58% 57%
Pin Heads 56% 53% 50% 21% 53% 13% 52% 44% 42% 43%
Green Fruit 3% 1% 1% 6% 4% 0%
Prune Cycle Emerged Shoot # 2.7 0.0 12.5 13.5 9.8 8.2 8.8 10.3 4.3 6.2
Week 8 5/31/21 to 6/04/21 Crop Cycle Stages % T1 Buds 0% 0% 0% 0% 0%
% T2 Buds 0% 0% 0% 0% 0% Present
% T3 Buds 0% 0% 0% 0% 0%
% T4 Buds 0% 0% 0% 0% 0%
% T5 Buds 0% 0% 0% 0% 0% Present Present
Bloom 3% 5% 10% 34% 7% 44% 11% 22% 16% 30%
Closed Flowers 3% 4% 10% 29% 6% 32% 9% 17% 16% 23%
Open Flowers 0% 0% 0% 6% 1% 11% 1% 4% 0% 7%
Pin Heads 66% 78% 82% 54% 76% 56% 87% 74% 84% 60%
Green Fruit 31% 17% 8% 12% 16% 0% 2% 4% 10%
Prune Cycle Emerged Shoot # 4.3 5.0 16.7 7.3 9.7 10.0 11.3 4.7 7.0
Week 9 6/07/21 to 6/11/21 Crop Cycle Stages Bloom 0% 0% 0% 2% 0% 5% 1% 2% 0% 3%
Closed Flowers 0% 0% 0% 2% 0% 3% 1% 2% 0% 3%
Open Flowers 0% 0% 0% 0% 0% 2% 0% 0% 0% 0%
Pin Heads 33% 49% 38% 63% 44% 55% 46% 69% 59% 46%
Green Fruit 67% 51% 62% 35% 56% 40% 54% 29% 41% 51%
Prune Cycle Emerged Shoot # 12.2 7.8 13.2 16.3 17.2 10.7 10.7 11.7 10.8 8.5
Week 10 6/14/21 to 6/18/21 Crop Cycle Pin Heads 13% 30% 38% 23% 13% 29% 38% 24% 14%
Green Fruit 87% 70% 62% 77% 87% 71% 62% 76% 86%
Prune Cycle Emerged Shoot # 13.7 8.2 13.5 19.5
Week 11 6/21/21 to 6/25/21  Crop Cycle Stages Pin Heads 8% 12% 12% 31% 7% 6% 26% 29% 14% 13%
Green Fruit 90% 87% 86% 68% 93% 94% 70% 70% 80% 82%
Red Fruit 1% 0% 0% 1% 0% 0% 0% 0% 0% 0%
Blue Fruit 1% 0% 1% 0% 0% 0% 0% 0% 0% 0%
Prune Cycle Emerged Shoot # 18.2 12.7 15.0 22.5 15.8 10.7 11.2 11.7 10.8 9.0
% Tip Die Back 17% 15% 14% 46% 25% 4% 12% 5% 9% 16%
Week 12 6/28/21 to 7/02/21  Crop Cycle Stages Pin Heads 4% 14% 13% 26% 8% 3% 25% 29% 14% 13%
Green Fruit 80% 75% 80% 66% 78% 97% 72% 68% 76% 83%
Red Fruit 7% 3% 2% 2% 4% 0% 0% 1% 3% 0%
Blue Fruit 9% 8% 5% 6% 9% 0% 2% 1% 4% 0%
Prune Cycle Emerged Shoot # 20.0 15.2 16.2 20.3 17.5 11.2 11.2 11.7 10.8 9.2
% Tip Die Back 45% 28% 35% 41% 33% 1% 6% 7% 9% 24%
Week 13 7/05/21 to 7/09/21  Crop Cycle Stages Pin Heads 2% 10% 8% 21% 7% 1% 20% 23% 11% 13%
Green Fruit 68% 63% 64% 57% 64% 95% 64% 61% 50% 77%
Red Fruit 5% 6% 13% 4% 6% 3% 5% 2% 8% 3%
Blue Fruit 26% 20% 15% 18% 23% 2% 11% 14% 30% 7%
Prune Cycle Emerged Shoot # 21.7 15.0 18.0 21.8 19.8 11.2 11.2 11.7 11.0 9.7
% Tip Die Back 78% 54% 41% 81% 86% 14% 7% 3% 9% 16%
Week 14 7/12/21 to 7/16/21  Crop Cycle Stages Pin Heads 3% 6% 2%   4%   19% 21% 9% 9%
Green Fruit 43% 34% 43%   30%   56% 55% 34% 61%
Red Fruit 12% 12% 5%   4%   6% 7% 7% 9%
Blue Fruit 44% 46% 50%   62%   38% 37% 57% 30%
Unmarketable Fruit 1% 8% 2%   3%   0% 1% 2% 0%
Prune Cycle Emerged Shoot # 19.0 13.7 16.3 19.0 17.2 12.2   12.3 11.2 9.7
% Tip Die Back 62% 58% 95% 95% 94% 10%   16% 12% 15%
Week 15 7/19/21 to 7/23/21  Crop Cycle Stages Pin Heads 0% 9% 9% 17% 4% 1% 21% 15% 8% 8%
Green Fruit 12% 17% 27% 22% 8% 52% 41% 26% 20% 48%
Red Fruit 4% 2% 3% 5% 3% 4% 2% 5% 10% 6%
Blue Fruit 76% 75% 68% 72% 79% 44% 56% 64% 70% 45%
Unmarketable Fruit 7% 5% 1% 1% 9% 0% 0% 5% 0% 1%
Prune Cycle Emerged Shoot # 16.3 14.8 15.7 15.8 16.2 12.2 11.7 15.0 11.2 10.0
% Tip Die Back 87% 79% 84% 97% 95% 9% 5% 85% 12% 15%
% Bud # 3% 9% 17% 62% 17% 0% 0% 13% 0% 0%
Week 16 7/26/21 to 7/30/21  Crop Cycle Stages Pin Heads Harvested 6% 10% 18% 3% Harvested 10% 7% Harvested 3%
Green Fruit 4% 20% 9% 4% 31% 19% 31%
Red Fruit 2% 2% 4% 3% 6% 1% 4%
Blue Fruit 81% 72% 86% 87% 63% 79% 64%
Unmarketable Fruit 13% 5% 0% 6% 0% 1% 1%
Prune Cycle Emerged Shoot # 17.8 15.7 16.0 15.8 16.8 12.3 12.2 12.3 11.7 10.7
% Tip Die Back 98% 80% 92% 94% 90% 15% 5% 4% 1% 3%
% Bud # 16% 13% 32% 91% 70% 0% 19% 20% 35% 17%

**The average number of emerged shoots are per 1 linear foot (#/1′), averaged across multiple clones per location.
*Bud percentages are based on the total number of buds sampled at each site.
Winterkill data were sampled prior to week 1.

Locations Warren Hope Searsport Blue Hill Ellsworth Deblois Montegail Jonesboro Wesley Marion
Week 17 8/02/21 to 8/06/21 Prune Cycle Average Bud # 0.69 1.61 1.39 1.25 0.89 0.67 0.92 0.83 0.44
Green Buds (%) 92% 97% 74% 100% 91% 96% 94% 100% 100%
Brown Buds (%) 8% 3% 26% 0% 9% 4% 6% 0% 0%
Week 18 8/09/21 to 8/13/21 Prune Cycle Average Bud # 1.00 2.03 #DIV/0! 2.10 2.00 0.75 0.53 1.33 1.11 0.61
Green Buds (%) 89% 93% #DIV/0! 59% 75% 81% 100% 94% 100% 64%
Brown Buds (%) 11% 7% #DIV/0! 41% 25% 19% 0% 6% 0% 36%
Week 19 8/16/21 to 8/20/21 Prune Cycle Average Bud # 0.94 2.49 1.86 1.92 2.22 0.64 0.74 1.11 0.81 0.44
Green Buds (%) 85% 67% 78% 25% 63% 57% 78% 65% 86% 100%
Brown Buds (%) 15% 33% 22% 75% 38% 43% 22% 35% 14% 0%