Salmonberry is known for its fruit, which bears resemblance to a raspberry. This plant earned its common name due to the fact that these berries were traditionally eaten by Native Americans with salmon or salmon roe. The taste of the berries themselves is somewhat bland but depends on the climate and site of growth.
I. Appearance and Characteristics
Rubus spectabilis, the salmonberry, is a species of bramble in the rose family Rosaceae, native to the west coast of North America from west-central Alaska to California, inland as far as Idaho. Like many other species in the genus Rubus, the salmonberry plant bears edible fruit, typically yellow-orange or red in color, resembling raspberries in appearance.
Rubus spectabilis is a deciduous, rhizomatous shrub growing to 1–4 metres (3–13 feet) tall and 9 metres (30 feet) wide, with a moderate growth rate of 0.3–0.6 metres (12-24 inches) per year. 30-40% of the plant’s biomass is underground. It has perennial (not biennial) woody stems that are covered with fine prickles, especially on new growth. The plant has golden or yellowish brown erect or arching stems (also known as “canes”) that often form thickets, like many other brambles in the genus Rubus.
The leaves are alternate, trifoliate (with three leaflets), 7–22 centimetres (3–8+1⁄2 inches) long and typically ovate in shape, with the terminal leaflet being larger than the two side leaflets, which are sometimes shallowly lobed. The margins of the leaflets are doubly serrated. The leaves are also stipulated and are smooth to slightly hairy on the top surface, compared to the underside, which are typically more pale and hairy. In late fall and winter months, salmonberry leaves will fall, and the plant remains dormant or maintains minimal shoot elongation during the winter.
The flowers are 2–3 cm (3⁄4–1+1⁄4 in) in diameter, with a calyx of five hairy sepals and five pinkish-purple petals that surround a cluster of stamens; they are produced between April and July, either singly or in clusters of 2 or 3. The flowers are perfect (bisexual), containing 75–100 stamens and many individual pistils with superior ovaries. While fruit production is largely dependent on the environment, there is an estimated growth of 30 fruits per 3m^2 (32 ft^2) and 17-65 seeds per fruit. Salmonberry sprouts mainly from the buds found on rhizomes, stumps, and root crowns of the plant. The flowers cannot self-pollinate and are instead pollinated by insects, hummingbirds, and beetles.
Salmonberries ripen approximately 30–36 days after pollination, from early May to late July in most of the Pacific Northwest and July to August in cooler Northern climates. They are 1.5–2 cm (1⁄2–3⁄4 in) long and resemble large shiny yellow to orange-red raspberries. The fruit pulls away from its receptacle, differentiating it from blackberries. Botanically speaking, the salmonberry is not a true berry, but instead an aggregate fruit made of many smaller drupelets. The fruits of the salmonberry plant exhibit polymorphism, as berries are often either red in color or a yellow-orange color. Studies have found that although both red and yellow-orange morphs have similar physical qualities, the red berries are more commonly consumed by birds, although this is likely not a strong enough selective pressure to determine color morph distribution alone; factors such as soil type (which affects germination), along with other unstudied factors are more likely responsible for the color polymorphism.
A similar species from Japan, the red-flowered raspberry (ベニバナイチゴ) was once considered a subspecies as R. spectabilis subsp. vernus. It is now reclassified as R. vernus.
In the wild, the fruit are typically eaten by birds, bears, and small mammals, among others, while the leaves, twigs, and stems are grazed on by herbivores such as deer, moose, mountain goats, elk, and rabbits. Populations of dense thicket growth can provide escape habitats for small animals, as well as nesting sites for birds.
In the spring, salmonberry flowering coincides with the migration of certain species of hummingbirds, which is crucial for its pollination. Birds and mammals also help with dispersion of seeds through their feces, while rodents and other burrowing animals may further help with dispersion. Some notable mammals crucial for the dispersion of seeds are the grizzly and American black bears, which can deposit 50,000 to 100,000 seeds in one pile of feces.
II. How to Grow and Care
Sunlight
Although you can find some Rubus species under the forest canopy, salmonberry loves sunlight. Full sun or partial shade (6-8 hours of sunshine) will be the best for it to thrive. Avoid too crowded bush to allow ample sunlight and air movement, which will prevent your plant from diseases.
Temperature
As a large genus, Rubus has a wide distribution range which means you are always likely to find a proper species or cultivar that grows well in your garden. Generally, Rubus species flourish in temperate zones, and adaptable to slightly harsh conditions. Select cultivars that may thrive in your garden, thus the preferable climate will encourage them to bear more edible fruits. Salmonberry prefers moist to slightly dry conditions, so it is important to avoid waterlogging.
Watering
Originating from the moist, forested regions of the Pacific Northwest, salmonberry thrives in environments that mimic its native habitat’s humidity. This species exhibits a preference for consistent moisture without being waterlogged, striking a balance between hydration and drainage. Its watering regimen should reflect moderate intervals, with watering once every 1-2 weeks. As an outdoor plant often found in riparian zones, salmonberry benefits from natural rainfall patterns but requires supplemental watering during dry spells. In terms of growth cycles, salmonberry’s water needs may fluctuate; during active growth periods in spring and summer, ensure soil remains evenly moist to support its vigorous development.
Soil
Salmonberry is not picky about soil, as long as the soil is slightly acidic and well-drained. The ideal soil pH range for it is 5.5–7 while a few species and cultivars of Rubus may tolerate slightly alkaline soil as well. Rich loamy soil mixing with some sandy soil can be a good option. Always remember to avoid the heavy clay soil because it can become soggy easily. Hilled soils that promote drainage can also be taken into consideration, instead of wet, flat field.
Fertilizing
For salmonberry, apply a balanced fertilizer enriched with macro-nutrients during its active growth in spring and early summer, tailoring applications to the plant’s life cycle phases. Initial growth benefits from higher nitrogen, whereas blooming and fruiting demand phosphorus and potassium. Use fertilizer sparingly, following package instructions, to avoid overfeeding that can harm salmonberry. Seasonal adjustment of the fertilization schedule supports health, promotes vibrant flowering, and enhances fruit yield. Ensure even distribution and water thoroughly post-application for effective nutrient absorption by salmonberry. Avoid fertilizing dormant salmonberry in late fall or winter.
Pruning
Pruning is important for salmonberry growers. Prune all canes that bore fruit this year down to the bottom right after harvest. All first-year canes should be cut about half to stimulate lateral growth from the side every late winter or early spring. Remove all suckers and trim overcrowded canes. Salmonberry grown in patches must be pruned to ensure that individual canes are not touching to avoid disease infections. Be sure to remove any thinned or pruned canes from the field because old canes left on the ground can harbor disease.
Propagation
Salmonberry propagates best in Autumn or Winter through cutting and layering techniques. Moderate difficulty may be experienced, but successful propagation is indicated by new shoot growth. Ensure moist soil and adequate sunlight for optimal results.
Transplanting
The best time to transplant salmonberries is S1 or autumn. This is due to the plant’s active growth initiation phase, providing easier acclimatization. Locate salmonberry in partial to full sun for optimal growth. Reminder: avoid transplanting in extreme heat, and water generously post-transplant.
Repotting
Repot salmonberry in late winter or early spring, before new growth begins, every 2-3 years to accommodate its medium size and bushy habit. Choose a wide, medium-depth container that allows for root expansion. Post-repotting, ensure salmonberry receives ample water, indirect light, and avoid fertilizing for a month to prevent shock and support recovery.
Pests and Diseases
Salmonberries are susceptible to many diseases, including mildew, fruit rot, rust, root rot, and viral and bacterial diseases. Their fruits, foliage, canes, roots, and crowns may also be damaged by pests such as beetles, aphids, mites, moths, among others.
III. Uses and Benefits
Ornamental uses
Salmonberry is a good choice for slopes and can assist in preventing erosion and slippage. It is commonly used in both ornamental and fruit gardens, as it has both attractive, pinnate leaves and also beautiful red-pink berries. The decorative shrub can over time form dense thickets. It grows well in open spaces in combination with red alders.
Medicinal and Culinary uses
Salmonberries are edible. The fruit has been referred to as “insipid”, but depending on ripeness and site, they are good eaten raw – whether red or golden – and when processed into jam, candy, jelly and wine. Native American people ate the young shoots or used it as a medicinal plant. The shoots were harvested during April to early June before they turned woody or tough, and were peeled, then steamed, boiled, or pit-cooked, and eaten (or less commonly, eaten raw). Traditionally, the berries and sprouts were also eaten with salmon or mixed with oolichan grease or salmon roe. They were not dried because of their high moisture content. It is still used as a food source and medicinal plant in regions of Alaska today.
Other uses by Native Americans include:
- Boiling the leaves with fish as a flavoring (by the Nuu-chah-nulth people)
- Using the leaves to line baskets, wipe fish, and cover cooking pits (by the Kaigani Haida people)
- Using the branches as a pipe stem (by the Makah people)
- Chewing and spitting the leaves (or bark in the winter) onto a burn as a treatment due to their astringent qualities (by the Quileute people)
- Boiling the bark in seawater to create a brew to clean infected wounds (especially burns) as well as reduce labor pains (by the Quinault people)
IV. Harvesting and Storage
Taste the fruit and it will tell you when it is time to harvest. Ripe fruits will be sweet and juicy. If they are still sour or tart, let them ripen a bit longer. Usually you can start harvesting from mid-summer till mid-fall, according to varieties. You should harvest the fruits when all dews or raindrops are dry to prevent molds. They have a short shelf life, so refrigerate them after harvest without washing. As for some sour species, process them into delicious jams or jellies.