Black Hawk Raspberry

Black Hawk was released by the Iowa State University fruit breeding program in 1955, at a point when black raspberry plantings across the upper Midwest were being lost to two problems at once: winter cold that killed canes back to the snow line, and anthracnose, a fungal disease that pits and girdles the canes in wet springs. Iowa State selected against both. Seventy years later, extension horticulturists still describe Black Hawk as the hardiest black raspberry available, and it sits in the short list of cultivars with useful anthracnose resistance alongside Jewel. Commercially it has been passed over by larger-fruited selections, and the plants are frankly vigorous and a little wild-looking next to tidier modern varieties. For a backyard planting or a food forest those are not faults worth much. What Black Hawk offers is a plant that comes through winters that kill other black raspberries, resists the disease that disfigures them, and ripens late enough to carry the black raspberry season a couple of weeks past the point where Bristol and Jewel have finished.

Black Hawk fruits reliably from zones 4 through 8, a range that takes in the cold-winter Upper Midwest and northern New England, the mid-Atlantic and Ozarks, and the cooler valleys of the Pacific Northwest. It needs 800 to 1000 chill hours, so it wants a genuine winter and is not a good match for the mild-winter South or coastal California. Plant in full sun for the heaviest crops; light afternoon shade is tolerated and helps in hot-summer regions. Give it well-drained loam or sandy loam at a soil pH of 5.5 to 6.5 — black raspberries will not tolerate wet feet, and heavy clay that puddles after rain invites root rot. Space plants 3 to 4 feet apart with 8 to 10 feet between rows so air moves through the canes and foliage dries quickly after rain, which is the single most effective thing you can do against cane disease. Avoid ground that has grown tomatoes, potatoes, peppers, or eggplant within the last three years, and pull out any wild brambles within a few hundred feet; both carry problems that move into a new planting. Water about an inch to an inch and a half a week during fruit development. The root system is shallow and fibrous, so mulch rather than cultivate around the crowns.

USDA Hardiness Zone: 4-8
AHS Heat Zone: 2-7
Chill Hours: 800-1000
Sun Requirements: Full Sun to Partial Shade
Soil pH: 5.5-6.5
Soil Type: Loam, sandy loam
Soil Drainage: Well-drained
Water Requirements: Medium (1-2 inches per week)
Drought Tolerance: Low
Heat Tolerance: Moderate
Plant Spacing: 3-4 ft apart
Container Suitability: No
How to Prune: Tip new primocanes at 18-24 inches in summer to encourage lateral branching; shorten laterals to about 18 inches in late winter and remove spent floricanes at ground level after harvest.

Black Hawk makes an upright, arching shrub 4 to 6 feet tall and 3 to 5 feet wide, vigorous enough that it reads closer to a wild black raspberry than to a domesticated one. Canes are biennial: a cane emerges and grows one season as a primocane, then flowers, fruits, and dies the following season as a floricane, while the crown itself persists for a decade or more. The canes are stout, distinctly thorny, and carry the waxy blue-white bloom typical of the species. Leaves are medium green above and a striking silvery-white underneath, so the planting flickers pale in a breeze; they turn yellow before dropping. Small white flowers, lightly fragrant, open in loose clusters. Unlike red raspberries, black raspberry spreads from the crown rather than by root suckers, so it stays where it is planted — but arching cane tips that touch soil in late summer will root and start new plants, which is how the species walks across ground if left unmanaged.

Mature Height: 4-6 ft tall
Mature Spread: 3-5 ft wide
Growth Habit: Upright, arching; vigorous and thicket-forming, close to wild type
Growth Rate: Fast
Foliage Type: Deciduous
Food Forest Layer: Shrub
Leaf Color: Medium green (upper surface), silvery-white (underside)
Fall Foliage Color: Yellow
Thorns?: Yes
Attracts Wildlife: Bees, Butterflies, Birds, Small mammals
Life Span: 10-15 years

Black Hawk is self-fertile. A single plant sets a full crop with no second variety required, which makes it practical for a small yard or a one-plant corner of a food forest. White flowers open from late April into early June depending on how the spring runs, in loose clusters on the previous season's canes. Although the flowers can pollinate themselves, bees do most of the actual work, and berries from well-visited flowers are noticeably better filled — a black raspberry is a cluster of individual drupelets, and each one needs its own pollination to swell. Crumbly, half-formed berries usually mean poor pollinating weather during bloom rather than anything wrong with the plant. Keeping flowering cover nearby and leaving the planting unsprayed during bloom is the most reliable way to get fully formed fruit.

Bloom Season: Early
Bloom Window: Late Apr - Early Jun
Pollination Requirements: Self-fertile
Pollination Mechanism: Insect-pollinated
Flower Color: White

Berries run about 0.6 to 0.75 inch across, medium-large for a black raspberry and a step up from Bristol, ripening to a glossy purple-black. The flavor is rich and deeply sweet with the winey depth that separates black raspberries from red ones, and the fruit is firm — it holds its shape in the picking bucket and does not fall apart even when carried a day past ideal ripeness, which is not true of every cultivar in this species. Harvest runs from early July into late July in temperate climates, placing Black Hawk at the late end of the black raspberry season and making it a useful partner to earlier varieties if you want to stretch picking across a month rather than a fortnight. Like all raspberries the fruit pulls free of its core, leaving the hollow cup that distinguishes it from a blackberry. Fresh fruit holds one to three days refrigerated, so most of a crop goes into jam, syrup, pie, or the freezer, where it keeps a year or more. Black raspberry makes what many people consider the best of all bramble jams, and the deep pigment gives it a color no other berry matches.

Ripening Season: Early
Harvest Window: Early Jul - Late Jul
Fruit Size: 0.6-0.75 inch
Flavor: Rich and deeply sweet with a wine-like finish; holds together without crumbling even when slightly overripe
Fruit Color: Glossy black (purple-black when ripe)
Fruit Texture: Firm
Bearing Habit: Floricane (biennial canes; primocanes year 1, fruit on floricanes year 2)
Years to Bear: 1-2 years
Storage Life: 12 months
Culinary Uses: Fresh; Baking; Cider/Juice; Preserves; Drying

Anthracnose resistance is the reason to grow this cultivar. Anthracnose is a fungal disease that speckles black raspberry canes with sunken purple-bordered spots, girdles them, and cuts both cane life and crop; it is the limiting disease for the species across the humid eastern half of the country, and most black raspberries have no defense against it. Black Hawk does, and university trials have repeatedly noted it performing better than susceptible cultivars through rainy growing seasons. Powdery mildew is a modest concern and rarely needs intervention. Orange rust is the disease to actually watch: it is systemic, meaning an infected plant never recovers, so dig out and destroy any plant whose spring shoots come up spindly with bright orange pustules on the leaf undersides rather than trying to treat it. The aphid-transmitted mosaic virus complex is the other real risk — it is why wild brambles near the planting are worth removing and why buying certified virus-free stock matters. Root rot is manageable through drainage alone. Among insects, spotted wing drosophila is the significant modern pest of all soft fruit; picking every two days through harvest and chilling fruit immediately keeps it in check without spraying. Crown and cane borers are handled by cutting out and burning wilted or swollen canes as you see them, and aphids by the same wild-bramble removal that limits virus spread. Good spacing, annual removal of spent canes, and clean sanitation carry this planting without chemical inputs.

Anthracnose: Resistant
Powdery Mildew: Moderately Resistant
Orange Rust: Moderately Susceptible
Raspberry Mosaic Virus Complex: Susceptible
Phytophthora Root Rot: Moderately Resistant
Spotted Wing Drosophila: Susceptible
Raspberry Crown Borer: Susceptible
Raspberry Cane Borer: Susceptible
Large Raspberry Aphid: Susceptible

• Tip the primocanes at 18 to 24 inches: pinch out the growing point of first-year canes in early summer. It forces side branches, and those laterals carry next year's crop — an untipped cane grows tall, flops, and fruits poorly.
• Cut spent canes the week you finish picking: floricanes die after fruiting anyway, and removing them immediately opens the canopy and takes diseased tissue out of the planting while the weather is still dry.
• Keep it away from wild brambles: a few hundred feet of separation from wild black raspberry and blackberry does more to protect the planting from virus than anything you can apply.
• Bury a cane tip to make new plants: in late summer, pin an arching primocane tip under an inch of soil. It roots in three or four weeks and can be severed and moved the following spring — free plants, and the way this species propagates itself.
• Pick every other day once ripening starts: frequent picking is the core organic control for spotted wing drosophila, and Black Hawk's firm fruit rewards it by holding condition better than most.

Our 365-Day Plant Guarantee: We ensure that our plants are delivered to you alive and healthy. If your plant does not survive its first year, you're eligible for store credit under these conditions:

1. Your location falls within the appropriate USDA hardiness zone for the plant variety (refer to our hardiness zone map).
2. You maintain the roots' moisture and plant within three days of delivery, following the instructions in our Planting Guide.

If you're concerned about your plant's health, please consult our guide, How to Tell if Your Tree is Dead or Dormant. Remember, our plants are shipped in a dormant state and may leaf out at different times based on their species. To check for plant vital