Strawberries

Family

Rosaceae

Habit

perennial

Height

0.3 m

Spread

1.5 m

Growth

medium

Lifespan

5 years

First yield

after 1 year

Hardiness

zone 5–9

Shade tolerance

full sun

Soil

Sand, Silt, Loam

Soil moisture

semi-dry – very moist

pH

5.5 – 7

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

Edible: Botanically the strawberry is not a berry but an aggregate of nutlets: what is eaten is the receptacle, which turns fleshy after flowering, while the true fruits sit on the outside as numerous small nutlets. In the wild strawberry they ripen from June to late July, reach one to two centimetres and only develop their unmistakable aroma at full ripeness; alongside minerals, fruit acids and soluble carbohydrates they hold around sixty milligrams of vitamin C per hundred grams. Garden strawberries are considerably larger, more watery and, depending on cultivar, pickable from May into October; the musk strawberry sits between the two and smells of musk. The fruit is made into jam and jelly, juice, syrup, fruit wine and sparkling wine, liqueur and fruit brandy, vinegar, punch, ice cream and compote, and of course used as a cake topping. Tea is brewed from the leaves. Pick dry and with the calyx attached — picked fruit keeps only one or two days.

Medicinal: Documented and still defensible is the use of the tannin-rich leaves as a tea for mild diarrhoea — the same principle as bramble and raspberry leaves. Tradition further records that the strawberry was held to be blood-cleansing and a remedy for gout and rheumatism, that the rootstock was used as a decoction for diarrhoea and bladder complaints, and that the crushed fruit was applied externally to blemished skin. No evidence of efficacy exists for these uses.

Other uses: Beyond the fruit, strawberries are above all area plants. Wild strawberry and the Fragaria x vescana hybrids form a closed, resilient carpet with their runners — hence the term strawberry meadow — and suit underplanting beneath fruit trees, bed edging, and banks where they are planted out and left to naturalise. On extensive-to-intensive green roofs wild strawberry is part of the standard range. In permaculture strawberries are listed as nutrient accumulators: they concentrate iron in their leaf mass, which returns to the cycle as mulch or through the compost heap. Tea can be brewed from the young leaves, and the flowers make a decorative edible garnish. Cultivars with variegated foliage or white fruit are grown purely as ornamentals.

Site: Strawberries are sun plants and want fresh, humus-rich, sandy-loamy and nutrient-rich soil on the slightly acid side; heavy waterlogged ground encourages root and rhizome disease and is out. The real siting decision, though, is the rotation: no strawberries should follow strawberries on the same ground for at least four years, and potatoes, tomatoes and other hosts of verticillium wilt are unsuitable as a preceding crop. Tagetes as a green manure before replanting has proved itself, because it suppresses nematodes. The position should be sheltered from wind so pollinators reach the flowers reliably — poorly pollinated flowers give misshapen fruit. Soft fruit above a closed ground cover attracts slugs, so a bed right against a meadow edge or the compost heap is a poor choice. For partial shade, edging and underplanting, reach not for the garden strawberry but for wild or alpine strawberries. Care: Plant from late July into August, and the bed will crop fully the following summer. Remove runners continuously where yield is the aim; for a new bed, let a few strong daughter plants stay and root. As soon as the first flowers open, put straw under the trusses: it keeps the fruit clean and denies grey mould the moisture it needs. After harvest, cut the old foliage off about a hand's breadth above the ground without damaging the crown, then mulch and keep evenly moist. Birds take their share, and netting helps. After three seasons yield and vigour drop noticeably, and the bed is started again elsewhere. The chief adversaries are grey mould, powdery mildew and verticillium wilt, along with strawberry blossom weevil, strawberry mite and slugs. In harsh areas the bed gets a brushwood cover over winter.

The standard route is propagation by runners: the strongest first daughter plant on a runner is guided into a sunken pot, pegged down and separated from the mother once rooted. With wild strawberry it is enough simply to detach the runners. Choosing healthy mother plants matters, because virus diseases pass on with the runners; for a new bed, certified young plants are the safer foundation. Alpine strawberries usually form no runners but a many-shooted crown; they are renewed by division or, better, from seed, because their vigour falls off after a few years. The seed needs light to germinate and is only pressed down, not covered. Two peculiarities belong here: the Fragaria x vescana hybrids run strongly and are all the better for a strawberry meadow because of it, and the musk strawberry is dioecious — without a male pollinator such as Cotta there is no crop at all.

Strawberries are better for insects than their reputation as a crop suggests — though much depends on which species is in the bed. For the garden strawberry some thirty-four wild bee species are documented as visitors, none of them specialists, with a modest nectar and pollen supply. The native wild strawberry sits well above that: around forty-five wild bee species, more than forty of which collect pollen, mining and furrow bees above all. Its nectar is easily accessible and additionally draws butterflies, beetles and flies. To this comes its value as a larval food plant: around twenty-two moth and butterfly species use wild strawberry foliage, among them the grizzled skipper. Pollination is not strictly required for fruit set, but it improves shape and size considerably; poorly visited flowers give deformed fruit. The fruit goes to birds, hedgehogs and mice, and the closed leaf carpet is cover and hunting ground for ground beetles and spiders.

Special notes: A false fruit - the fleshy receptacle is what is eaten, the nutlets on the outside are the true fruits; yield and vigour drop from the third season start a new bed; no strawberries after strawberries, potatoes or tomatoes (verticillium) at least 4 years' break; plant late July/August full crop the following year; straw from first flowering against grey mould+soil splash; remove runners yield / leave them propagation; alpine strawberries usually runnerless division or seed (needs light to germinate); musk strawberry is dioecious pollinator cultivar required; poor pollination misshapen fruit; keeps only 1-2 days

The temperate zones of the northern hemisphere, plus the west coast of South America. The genus Fragaria comprises around twenty species and is represented in Europe, northern Asia, China, the Himalaya, South-East Asia and North America; the Chilean strawberry Fragaria chiloensis extends down the Pacific coast as far as Chile. Wild strawberry, musk strawberry and green strawberry are native to Central Europe, while the scarlet strawberry comes from the USA, Canada and Alaska. Today's garden strawberry, by contrast, is no wild species: Fragaria x ananassa arose around 1750 in Brittany from repeated chance crosses between the North American scarlet strawberry and the South American Chilean strawberry. Spreading from northern France and Holland, it displaced the musk strawberry that had dominated German gardens within a few decades.

The wild species of the genus are plants of margins and clearings, not of closed forest. Wild strawberry occupies woodland edges, cleared ground, banks and track sides on sunny to partly shaded, moderately moist to moderately dry, nutrient-rich and somewhat loamy soils; heavy and waterlogged ground rules it out, because it encourages root and rhizome disease. Musk strawberry grows by preference along woodland edges on moderately moist soils in sheltered positions and copes badly with the sharp temperature swings of spring and with night frosts. The North American scarlet strawberry occupies open woodland and forest clearings between 1,200 and 3,300 metres. What they share is a place on the edge: light but not drought, and a soil that warms quickly in spring.