Blueberry
Can I Grow Duke?
Duke is the early-season champion — blooming late to dodge spring frosts but ripening early to beat the summer heat. Large, firm berries with mild, sweet flavor that holds up in storage and shipping.
Growing Requirements
Chill Hours
800
Hardiness Zones
4-5-6-7
Harvest
Late May to early July
Results
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Pruning dates, harvests, spray schedules, what worked. The gardeners who get the most from their trees are the ones who kept records.
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About Duke
Duke is the early-season champion — blooming late to dodge spring frosts but ripening early to beat the summer heat. Large, firm berries with mild, sweet flavor that holds up in storage and shipping.
Duke requires 800 chill hours — the number of hours between 32°F and 45°F during winter dormancy. Without enough chill, the tree may fail to flower properly or produce poor fruit.
⚠️ Common Challenges
Requires heavy pruning to maintain fruit size; vigorous growth can become unruly; needs consistent moisture.
❌ Common Misconception
Can I grow Duke in Zone 8 or warmer?
No. While Duke is listed for zones 4-7, it requires 800 chill hours to produce fruit. Warm zones like 8+ typically receive only 200-400 chill hours. The tree may survive but will not fruit reliably. Consider low-chill alternatives like Anna apple (200h) or Tropic Snow peach (200h) instead.
If you plant it, write it down.
Variety, rootstock, planting date — and every pruning and harvest after that. Future you will thank you.
Free for up to 30 plants. No card needed.
Other Blueberry Varieties
Chill hour data from ERA5 reanalysis (Copernicus/ECMWF). Variety information compiled from university extension services.