Filberts are easy to grow and very productive! Filberts can be grown in USDA Zones 5-9. They are by far the most important nut crop grown commercially in the Pacific Northwest. This small tree prefers a cool, wet climate. Filberts flower in mid-winter. Humid, windy weather is ideal for distributing pollen to the tiny red female flowers. By the end of August nuts are ripe. They drop in September. We offer the best new filbert blight resistant cultivars from the Oregon State University breeding program. Each needs a second variety as a pollinizer. Prohibited to ship to AZ.