The ‘Hardyblue’ blueberry is a popular and resilient choice for home gardeners. This Northern Highbush variety is valued for its adaptability and generous harvests. Its appeal extends beyond fruit production, offering ornamental value with attractive foliage and bark throughout the seasons.
Hardyblue Blueberry Characteristics
The ‘Hardyblue’ blueberry is well-regarded for its significant cold tolerance, making it suitable for USDA Zones 4-7. This resilience is a primary reason for its name. The shrub exhibits an upright, spreading growth habit, typically reaching a mature height of 4 to 7 feet with a similar spread. Its smooth, brick-red bark and dark red branches provide visual interest in winter, while its glossy green leaves transform into striking shades of yellow and red in the autumn.
In mid-summer, ‘Hardyblue’ produces clusters of medium-sized, round berries known for their exceptionally sweet taste and juicy texture. Their superior flavor makes them ideal for fresh eating, baking, and preserves. This variety is semi-self-fertile; however, planting it with another Northern Highbush variety that blooms around the same time significantly improves fruit set and yield.
Planting Hardyblue Blueberries
Planting ‘Hardyblue’ blueberries requires careful site selection. These plants thrive in full sun, ideally receiving at least six to eight hours of direct sunlight daily, though partial shade may reduce fruit production. Good drainage is essential, as blueberry roots will suffocate in waterlogged soil. Avoid low-lying areas that collect water or are prone to late frosts.
‘Hardyblue’ blueberries require highly acidic soil, with an optimal pH range typically between 4.0 and 5.5. Most garden soils are not naturally this acidic, so amendments like elemental sulfur or sphagnum peat moss are needed to lower the pH. Test your soil pH several months to a year before planting, as sulfur takes time to react and should be thoroughly mixed into the top 6 to 8 inches of soil in the entire planting area. When planting, ensure proper spacing, typically 3 to 4 feet between plants for optimal pollination and growth. After placing the plant, handle the root ball gently and water thoroughly to settle the soil around the roots.
Hardyblue Blueberry Care
Consistent care is crucial for ‘Hardyblue’ blueberries. These plants have shallow, fibrous root systems requiring consistent moisture, especially during flowering and fruiting periods. Provide 1 to 2 inches of water per week, ensuring the soil remains moist but not waterlogged. Mulching with materials like pine bark or aged wood chips helps retain soil moisture, moderate soil temperatures, and suppress weeds.
Fertilize with acid-loving plant formulations in early spring before new growth appears and again after harvest. Blueberries prefer nitrogen in the ammonium form, so use fertilizers containing ammonium sulfate, urea, or cottonseed meal, avoiding nitrate forms which can be harmful. Spread granular fertilizers around the plant’s drip line, avoiding direct contact with the crown, and water them in thoroughly. Prune in late winter or early spring while the plant is dormant. This involves removing dead or weak canes, thinning out older, less productive branches, and opening up the plant’s center to improve air circulation and light penetration, which encourages new growth and better fruit production.
Blueberries are susceptible to common pests like Japanese beetles, mites, and flea beetles, and diseases such as mummy berry, powdery mildew, and stem canker. Regular inspection of plants helps identify issues early. Preventative measures, such as maintaining good air circulation through proper spacing and pruning, and ensuring appropriate soil conditions, can significantly reduce the risk of disease. Mummy berry, a fungal disease, can be managed by removing infected berries and shoots, and by burying mummified fruit under mulch to prevent spore release.
Harvesting and Enjoying Hardyblue Blueberries
‘Hardyblue’ blueberries typically ripen mid-season, from mid-summer onwards, depending on your climate zone. The most reliable indicator of ripeness is the berry’s color; it should be fully blue with no hints of pink or green, especially around the stem end. While a berry may appear blue, it continues to sweeten for several days after coloring, so waiting a few extra days after it turns fully blue can enhance flavor.
To harvest, gently roll the berry between your thumb and forefinger. A ripe berry will detach easily from the stem with little effort. If it requires pulling, it is not yet fully ripe. Blueberries on a single bush ripen at different times, so plan to pick every 5 to 7 days over several weeks to ensure you gather them at their peak sweetness. Freshly picked ‘Hardyblue’ blueberries are delicious on their own, in baked goods like muffins and pancakes, or preserved through freezing for later enjoyment.