|Arbutus unedo subsp. var.||Strawberry Tree|
The Strawberry Tree (Arbutus unedo L.) is an evergreen shrub or small tree in the family Ericaceae, native to the Mediterranean region and western Europe north to western France and Ireland. Due to its presence in South West Ireland, it is also known as Irish strawberry tree, and Killarney strawberry tree.
The Strawberry Tree grows to 5-10 m tall, rarely up to 15 m, with a trunk diameter of up to 80 cm. Zone: 7-10
The leaves are dark green and glossy, 5-10 cm long and 2-3 cm broad, with a serrated margin.
The fruit is a red aggregate drupe 1-2 cm diameter, sometimes called arbutus-berry, with a rough surface, maturing 12 months at the same time as the next flowering. The fruit is edible, though many people find it bland and mealy; the name 'unedo' is explained by Pliny the Elder as being derived from unum edo "I eat one", which may seem an apt response to the flavour. They mainly serve as food for birds but in some countries they are used to make jam and liqueurs.
An evergreen Tree growing to 9m by 8m at a medium rate.
It is hardy to zone 7 and is not frost tender. It is in leaf all year, in flower from October to December, and the seeds ripen from October to December. The flowers are hermaphrodite (have both male and female organs) and are pollinated by Bees. The plant is self-fertile.
Unlike most of the Ericaceae, it grows well in limy soils. It is best planted in a sheltered position due to its late flowering habit (see first paragraph). When grown as a tree rather than a multi-stemmed shrub, it is important to select one stem that becomes the main trunk, keeping any other basal sprouts pruned off. It prefers well-drained soil and only moderate amounts of water. The Strawberry Tree is naturally adapted to dry summers, though also growing well in the cool, wet summers of western Ireland. It is therefore useful for planting in areas with a dry-summer climate, and has become a very popular garden specimen in California and the rest of the west coast of North America. It is hardy in USDA Hardiness Zones 8 to 10.
The plant prefers light (sandy) and medium (loamy) soils, requires well-drained soil and can grow in heavy clay soil. The plant prefers acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It requires dry or moist soil. The plant can tolerate maritime exposure. It can tolerate atmospheric pollution.
Requires a nutrient-rich well-drained moisture-retentive soil in sun or semi-shade and shelter from cold drying winds, especially when young[11, 200]. Grows well in heavy clay soils and in dry soils. Most species in this genus require a lime-free soil but this species is fairly lime tolerant[11, 200]. Succeeds in fairly exposed maritime positions[166, 200]. A tree in a very exposed position at Rosewarne in N. Cornwall was looking rather tattered in April 1987 but it was 4.5 metres tall and carrying a very good crop of immature fruit[K]. Tolerates industrial pollution. Plants have withstood temperatures down to -16°c without injury at Kew. They grow very well in S.W. England, fruiting well in Cornwall[49, 59]. Plants resent root disturbance and are best placed in their final positions whilst young[11, 134]. Give them some protection in their first winter. The strawberry tree flowers in November and December, the fruit takes 12 months to ripen and so the tree carries both mature fruit and flowers at the same time and is incredibly beautiful at this time[K]. The flowers have a soft honey scent. There are a number of named varieties developed for their ornamental value. 'Elfin King', 'Croomei' and 'Rubra' are all small forms that fruit well when small. The variety 'Rubra' was 1.2 metres tall at Kew in late 1990 and was laden down with fruits and flowers[K]. 'Elfin King' only reaches a height of 1 metre, comes into bearing when young and fruits well. It is ideal for container culture. 'Croomei' is said to be a more reliable fruiting form.
Seed - best surface sown in a cold frame as soon as it is ripe. Stored seed should be soaked for 5 - 6 days in warm water and then surface sown in a shady position in a greenhouse. Do not allow the compost to become dry. 6 weeks cold stratification helps. The seed usually germinates well in 2 - 3 months at 20°c. Seedlings are prone to damp off, they are best transplanted to individual pots as soon as they are large enough to handle and should be kept well ventilated. Grow them on in a greenhouse for their first winter and then plant out in late spring after the last expected frosts[K]. Basal cuttings in late winter. Cuttings of mature wood of the current season's growth, November/December in a frame. Poor percentage. Layering of young wood - can take 2 years[1, 200].
Pests and diseases
- 'Compacta' - A dwarf cultivar, it is said not to flower very freely.
- 'Croomei' - A dwarf-growing cultivar, it is said to be a reliable fruiting form.
- 'Elfin King' - The fruits are up to 25mm in diameter and have a sweet flavour[183, K]. A slow-growing compact plant, often no more than 1 metre tall. It comes into bearing early, sets fruit freely and is ideal for container growing.
- 'Rubra' - Smaller than the species type, this form grows to about 2 - 3 metres in height, fruiting abundantly even when only 60cm tall[K].
- ↑ Natural History 15.28.99
- Plants for a Future - creative commons text incorporated
- Standard Cyclopedia of Horticulture, by L. H. Bailey, MacMillan Co., 1963