Juniperus sabina Seeds | Savin Juniper
LATIN NAME: Juniperus sabina
COMMON NAME: Savin Juniper
Plant Profile
Savin carries juvenile and adult foliage at once. The adult leaves are scale-like, pressed against the stem in overlapping ranks, dull bluish-green, each with a resin gland on the back that releases the smell when you crush the shoot. The juvenile leaves are short, sharp needles, persisting in the shaded interior of the bush and returning on vigorous regrowth after hard cutting.
Cones are borne on separate plants, so a seed crop needs both sexes. The female cone is berry-like, a few millimetres across, bluish-black under a grey waxy bloom, soft and resinous when ripe, and it carries one to three hard seeds with a rough coat. Because the seeds are enclosed in flesh rather than shed from a woody cone, savin depends on birds to move it, and the seed is dropped with a little fertiliser.
Use savin where you need evergreen cover on ground that dries out, and place it with one eye on what grows nearby, because it is half of a two-host fungus.
‘Tamariscifolia’ is the classic low, dense, fountain-like form; ‘Buffalo’ is hardier and fuller in the middle, ‘Arcadia’ keeps good winter colour, and ‘Broadmoor’ stays compact enough for a large rock garden. Space them a metre or more apart, and do not enrich the soil, because savin on fat ground opens in the centre and loses its shape.
Gymnosporangium rusts need two hosts to complete a life cycle, and savin carries the pear rust fungus whose other half is a pear tree. In mild, wet spring weather the juniper tissue swells into gelatinous orange-brown horns that release spores onto the wind, and the pear shows orange leaf spots later. Keep savin away from orchard pears, and note that rose-family plants nearby, including an acute-leaved cotoneaster, can host the same rusts.
Science & Biotechnology
The foliage also contains podophyllotoxin, an aryltetralin lignan better known from the mayapples of the genus Podophyllum. Podophyllotoxin is the starting skeleton for the semi-synthetic anticancer drugs etoposide and teniposide, and the search for a steadier supply of that skeleton has led researchers to screen junipers, savin among them, as alternative sources.
Uses & Benefits
Savin belongs among the few conifers whose chemistry is studied for reasons with nothing to do with timber. Its foliage yields an essential oil, and it also carries lignans that drug developers have chased for decades.
Steam distillation of savin twigs gives a pale oil in which sabinene and sabinyl acetate dominate, with sabinol, terpinen-4-ol, limonene and pinene making up the rest. The oil is a violent skin and mucous-membrane irritant and a poison taken internally; older herbals recommended it for purposes for which it should never be used.
Growing from Seed
Juniperus sabina is a low, spreading evergreen, often less than a metre tall but several metres across, with prostrate branches that root where they lie. In the mountains it occupies stony slopes, cliff ledges and screes, usually on limestone, from southern Europe to the Altai, and it grows best where little else will: full sun, thin soil and sharp drainage.
Juniper seed is built to wait, and the two things that break the wait are abrasion and moisture in sequence.
Soak the cleaned seeds for a day, then rub them in damp coarse sand inside a jar to wear the resinous coat, or nick the hard end with a file. After that the seed wants a warm, moist spell followed by a cold one: mix it into damp vermiculite, keep it warm and moist, then move the bag to a cold place for the rest of the winter. Sow 5 mm deep in a gritty mix, and never empty a tray that still holds seed.
Prick the seedlings out when they are 3 to 4 cm tall, taking a ball of compost with each root. Plant out at 15 to 20 cm, water through the first summer, then leave the plant alone: savin resents wet feet far more than drought, and root rot in a heavy, wet soil is the commonest reason a mature specimen dies out of the middle. A hard jet of water in early summer keeps scale insects and spider mites down.
Our Take
Savin is the plant I recommend to anyone defeated by a dry south-facing bank: give it sun, gravel and space, and shear it once after the worst of the winter. If you want a juniper that takes more shade and more water, look at the Chinese juniper, and for the American plains the blue-berried Rocky Mountain juniper is the better tree. Keep savin away from fruit trees, and the plant will give you twenty years of evergreen cover for very little attention.
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