Rubus illecebrosus aka Strawberry Raspberry

Rubus illecebrosus is known as strawberry-raspberry or balloonberry. It belongs to the rose family, Rosaceae. This plant comes from central and southern Japan. Its range includes Honshu, Shikoku, and Kyushu. It grows in thickets and on disturbed ground. Gardeners sometimes grow it for its edible fruit. It has also become naturalized in parts of Europe.

This spreading plant forms a thorny, perennial shrub. Much of its growth dies back over winter. Only a small woody base remains through the cold months. This makes it a subshrub rather than a fully woody shrub. NC State describes its leaves as deciduous. The green, compound leaves have a prickly feel. Hairs also occur on the plant. Its coarse growth and thorny stems can form a barrier. It spreads freely where conditions suit it.

White flowers open from April to June. They grow alone or in small groups of two or three. Each flower has five petals and offers nectar to pollinators. The flowers give way to red, oblong fruit in summer. Each fruit consists of many small drupelets joined together. NC State records fruit up to three-quarters of an inch long. Plants For A Future reports fruit around an inch across. These accounts suggest some variation in fruit size.

Choose full sun for cultivation, though it also tolerates light shade. It prefers moist soil that drains well. It grows in sand, loam, and clay. NC State lists tolerance of acid, neutral, and alkaline soils. The same source places it in USDA zones 4–8. Growth proceeds at a moderate rate, with moderate upkeep. Its spreading habit suits ground cover, hedges, and edible gardens. It also has a place in woodland and pollinator gardens. Winter dieback can leave gaps for other plants to enter.

Keep its tendency to spread in mind when choosing a site. Sources warn that it can become weedy or invasive. NC State lists raspberry cane borer and rednecked cane borer as pests. It also notes honey fungus, but reports few other problems. The fruit can be eaten raw or cooked. Reports of its taste range from sweet but bland to sour or bitter. Cooking may bring out more flavour. Plants For A Future lists no known hazards or medicinal uses. That source also records a purple to dull-blue dye from the fruit.