Goji berry

Family

Solanaceae

Habit

Shrub

Height

2.8 m

Spread

4 m

Growth

fast

Lifespan

60 years

First yield

after 3 years

Yield per plant

up to 4 kg a year

Yield in cultivation

up to 4 t/ha

Energy yield

1360 kcal per m² a year

Hardiness

zone 6–9

Shade tolerance

partial shade

Soil

Sand, Silt, Loam

Soil moisture

dry – very moist

pH

5.5 – 6.5

Synonyms

Goji

Times apply to the northern hemisphere in a temperate climate and shift with altitude and cultivar.

Edible: Fruit - raw or cooked. The fruit is a berry with a diameter of about 2 cm, having a mild sweet licorice flavor. Only fully ripe fruits should be consumed. Young shoots can be cooked and used as a vegetable, offering a slightly cress-like taste, also described as minty. The leaves wilt quickly after harvesting. Caution is advised, see notes above. The leaves can be used as a tea substitute.

Medicinal: Traditional Chinese Medicine treats two parts of this plant separately. The dried berries, gouqizi, are regarded there as a means of strengthening liver and kidneys and are used for weak eyesight, dizziness and exhaustion; they are food as much as medicine and go into soups, teas and rice dishes. The dried root bark, digupi, is traditionally used for persistent fever and heat conditions. Both are traditional applications without robust proof of efficacy by present-day standards; the European marketing as a superfood rests above all on the content of zeaxanthin and lutein, which contribute to the supply of the retina.

Other uses: Beyond its fruit, goji is used above all as a shrub with a job to do. Its far-reaching, dense root system binds sandy soils, dunes and banks and is used for slope stabilisation - the very trait that makes it a nuisance in a border. As a free-growing thorny hedge it forms an impenetrable boundary within a few years, giving cover and holding back livestock; coppiced regularly it stays dense. It tolerates wind and coastal climate but reacts sensitively to salt, so it does not belong in the front dune line or along roads treated with de-icing salt. For small gardens and balconies container culture is the most sensible form, since it deals with the suckers at the same time. The young leaves are cooked as a leaf vegetable in East Asia; in the EU, however, only the berries are approved as food. Ornamental cultivars are planted for the violet flowers and the long fruiting season.

Site: Full sun on free-draining, moderately fertile soil; poor soils actually give a better fruit set, while rich soils produce nothing but growth. More important than the soil is the question of how to get rid of it again: goji throws vigorous root suckers and layers its arching branches at the same time, so that within a few years it spreads metres and forms dense thicket. In Europe it counts as invasive because it can displace native ruderal vegetation; it has no place beside natural areas, dry stone walls or species-rich grassland. In the garden it belongs inside a rhizome barrier, in a large container, or in a spot that is mown all round. The shoots carry thorns and do not belong beside narrow paths, seating areas or children's areas. Birds carry the seed far beyond the plot. It is sensitive to salt, so roadside positions are out. Care: The shrub is undemanding, hardy to about -25 degrees and copes well with drought; water only in the planting year and in long dry spells. Feed not at all or very sparingly. Pruning decides the yield: fruit is borne on one-year wood, so thin hard in late winter, take out old wood and build an upright framework of a few leaders - unpruned the shrub grows straggling and flops to the ground, where the branches root. A support or wire frame keeps it upright and the fruit clean. Powdery mildew appears regularly and is limited by airy pruning; aphids and occasionally slugs attack young growth. Harvest continuously from August to October, most gently by shaking onto a cloth, since the soft berries darken where handled.

Goji can be propagated several ways, with the vegetative methods reserved for named cultivars. Suckers are the easiest: rooted root shoots are severed in autumn or early spring and planted straight into their new position. Layering is equally reliable - pin an arching shoot to the ground in summer and earth it up lightly, and by the following year it has rooted and can be separated. Softwood cuttings of half-ripe shoots, 5 to 10 cm long, root at a high percentage from July to August given even moisture and slight bottom heat; hardwood cuttings from the winter prunings also succeed in an outdoor bed. Seed raising is straightforward: wash the seed from fully ripe berries, dry it and sow it shallowly in spring at 18 to 22 degrees, where it germinates promptly without any chilling. Seedlings turn out uneven, however, come into bearing later and often carry smaller fruit, so this route is only worthwhile for hedging.

Goji is a neophyte from East Asia for which no reliable species counts for wild bees or beetles exist in Central Europe. Its strongest argument is the length of its flowering: the small violet funnel-shaped flowers open continuously from June to September and thus bridge the midsummer gap, when many spring bloomers are long finished. Pollination is by bumblebees and bees, and self-pollination is possible as well. As a caterpillar host it is accepted by hawkmoths, among them the tobacco hornworm and the death's-head hawkmoth, which arrive as migrants from the south. The berries ripen from August to October and are eaten by birds, which also disperse the seed; that is one reason for its readiness to spread. The thorny thicket gives birds and small mammals good cover and nesting opportunities. Anyone chiefly wanting to support native insects is better served by dogwood, dog rose or guelder rose.

Special features: tolerant to (sea) wind, forms many runners; 6500 plants are planted per hectare; can be stored dried for 1-2 years; recommended varieties for fresh consumption are: 'Turgidus', 'No.1 Lifeberry'; Wild form tastes rather bitter peppery and is more suitable for drying;. susceptible to powdery mildew, prefers sandy soil as a pioneer plant;

East Asia, centred on northern China. The exact homeland is disputed, because the species has long been cultivated and has escaped widely; the range given today runs from south-eastern Europe through Central Asia to China, but the focus of wild occurrence and the entire commercial crop lie in East Asia. The north-west Chinese region of Ningxia on the Yellow River is the classic growing area and still supplies most of the world crop. Goji reached Europe in the 18th century as an ornamental and hedging plant and has been naturalised ever since; in Germany the escaped populations are concentrated in the east and are scarcer in the west. Growing it for the fruit market has only been an issue in Central Europe for a few decades.

Goji is a full-light plant of open, disturbed ground. In Central Europe it turns up as a neophyte along path edges, railway embankments, walls, hedges, banks and waste ground, often on free-draining, moderately fertile soil in ruderal situations. It prefers neutral to slightly acidic, moderately dry substrates and tolerates neither salt nor heavy metals. The straggling, arching thicket with its strong suckers forms dense, impenetrable stands that can displace native ruderal vegetation - which is why the species is regarded as invasive in Europe, though it is not on the EU list of species of Union concern. In its region of origin it grows under markedly continental conditions with hot dry summers and severe winters, and it is hardy to about -25 degrees.