Editorial: April 2010
Forest Garden Perennials for 2010
Last month I mentioned that we were about to start sowing seed for the big 2010 plant giveaway at the Rhayader Green Fair in July. Last year’s seedling swap was so successful that we thought we would do something even more ambitious this time, and focus on perennial vegetables and herbs, including lots of pollinator-friendly plants to help the bees and other pollinating insects do their job and maintain populations.
I was talking about this at a meeting last week and someone asked ‘what are perennial vegetables?” So I thought lots of other people might like to know the answer to that, and I am sharing my list of species with you, together with the wonderful information on the habits, requirements and uses of these plants as set out by the seed provider - the wonderful Agroforestry Catalogue – details at the end of this article.
All of these plants would be useful in a Forest Garden for understorey planting between and around fruit bushes and fruit and nut trees. They would also be good to establish in your vegetable garden so you always have something that perpetuates itself year on year and increases over time. Lots of the plants we think of as wildflowers are great for bees and other pollinators (see Sanna Burns’ recent article on this website), and make a pretty and medicinal or culinary addition to flower borders and marginal areas in the garden, or mixed in with the herb patch. All these species are for sowing in spring.
Here is my 2010 list, in alphabetical order.
Note: Species marked *** need special treatment. CS means cold stratification – ie. You mix the seed with damp silver sand in a plastic bag and keep it in the fridge or similar cold place for the stated number of weeks before sowing. WS means warm stratification. Some seeds need a period of both to germinate. Obviously you only order these varieties if you have left yourself enough time!
SC = Scarification. This can mean a soak in hot water to help germination , or rubbing lightly between sheets of sandpaper to abrade the hard waxy coating of the seed before sowing. Full details of these processes are on Martin’s website – see end of article.
Yarrow. Mat-forming perennial, spreading via rhizomes. Edible leaves, medicinal, bee plant, ground cover, mineral accumulator. Likes sun and a well drained site; hardy to –40°C
Korean mint. Perennial growing to 60 cm (2 ft) high or more, with spikes of blue flowers much loved by bees. The leaves are anise-flavoured and used as a flavouring and for teas; also medicinally in Chinese medicine. Likes a well-drained soil and sun; hardy to -10ºC or so.
Golden garlic. Perennial from Southern Europe growing to 30 cm (1 ft) high which likes sun or light shade. It has edible leaves, flowers and bulbs, all with a mild garlic flavour. Bees like the flowers. Hardy to -15°C.
Daffodil garlic. A perennial from Europe which produces edible, garlic-flavoured bulbs, young leaves (excellent in salads) and flowers (good in salads). Leaves are retained in most winters and can be used in winter salads; top dies down in midsummer until autumn. Prefers sun, though it is one of the few Alliums to tolerate deep shade in a well-drained location. Hardy to -12°C.
Allium carinatum pulchellum
Keeled garlic. Bulbous, clump-forming perennial to 60 cm (2 ft) high, virtually evergreen, with rich purple flower in summer. Does not produce bulbils. Edible leaves & flowers – garlic flavour. Likes sun and a well-drained site; hardy to -15°C
Chives. Well known perennial from Europe, growing to 60 cm (2 ft) high when it flowers. Usually grown for the edible leaves, excellent raw in salads or cooked. The flowers can also be eaten, and bees love the flowers. Likes sun or light shade. Hardy to -23°C.
Garlic chives, Chinese chives. Chinese perennial growing to 50 cm (20”) high which needs a sunny site. Well known for its edible leaves with a garlic flavour; also edible are the bulbs, seeds and flowers. Also used medicinally. Bees like the flowers. Hardy to -15°C.
Ballhead onion. Vigorous bulbous perennial to 60 cm (2 ft) high with purplish-pink flowers in summer. Edible bulbs, leaves, young shoots. Likes sun and a well-drained site; hardy to -20°C
Ramsons, wild garlic. A perennial woodland plant forming dense carpets of garlic-flavoured foliage from early spring until midsummer. Excellent as a garlic-substitute; flowers and bulbs are edible as well as the leaves - all being garlic flavoured. Has similar medicinal properties to garlic, and a good bee plant. Hardy to -23°C.
False indigo. A medium Sized North American shrub, growing to 3-4 m (10-13 ft) high. It is a nitrogen-fixing legume. The crushed seeds have been used as a condiment (though they may not be wholesome); resinous pustules on the plant contain an insecticidal compound effective against aphids and cattle flies. The plant contains small amounts of indigo pigment and can be used to make a blue dye. A good wildlife plant. Needs a well-drained soil and sun or light shade; hardy to -40°C.
Arbutus unedo (note: this one becomes a TREE)
Strawberry tree. A bushy evergreen tree from southern Europe, reaching 10m (32 ft) high. Produces abundant red strawberry-like fruits 20 mm across with a delicate flavour. Good in hedges; good source of late nectar and pollen for bees in October-December. The bark and leaves have been used both for tanning and medicinally. Growth 2.5m (8 ft) in 10 years; hardy to about -15°C.
Tarragon. Perennial plant from southern Russia, source of the familiar herb. As well as the edible leaves, the essential oil is used as a flavouring and the leaves are used medicinally. Likes a dry sunny site; hardy to -15°C. Watch out for slug predation.
Swamp milkweed. Perennial growing to 1 m (3 ft) high with pinkish-purple flowers from summer to autumn. All the milkweeds have edible young shoots (cooked like asparagus) and flowers buds (with a pea flavour). A fibre is produced from the stems, and the seed floss is water-repellent and formerly used in life jackets. The stems produce a latex in small amounts which makes a high quality rubber. Prefers a moist soil and sun; protect young plants from slugs. Hardy to -35ºC.
Calamint savory, Lesser calamint. A wide spreading perennial growing to 60 cm (2 ft) high, with stems rooting as they go, with white-lilac flowers in profusion from spring to summer. The leaves are used as a flavouring and for teas, also medicinally; bees love the flowers. Makes a very good ground cover plant. Likes any reasonable soil and sun or part shade; hardy to -20ºC.
Giant bellflower. A native harebell, a perennial growing 1.2 m (4 ft) high, which self-seeds readily and makes a good ground cover. Leaves, young shoots and flowers are edible, good in salads. Bee plant. Likes part or full shade, hardy to -35°C.
Creeping bellflower. A perennial from North America, growing up to 1.2 m (4 ft) high, which self-seeds rampantly and makes a good ground cover. As well as having pleasant edible leaves, this species also has a nice edible root (raw or cooked), and dyes have been obtained from the aerial parts. Likes sun or part shade; hardy to -35°C.
(Montia sibirica) Siberian purslane. Not from Siberia, this North American short-lived perennial grows 20 cm high in a any moist soil in sun or part or full shade. The leaves are edible, raw (an excellent salad plant – beet flavour) or cooked, and the plant can be used for ground cover - it self-seeds freely. Hardy to -35ºC.
Cardoon. Tall perennial from the Mediterranean region growing to 2 m (7 ft) high. The blanched leaf stalks are cooked as a celery-like vegetable; also edible are the cooked roots, young leaves & stalks, and unopened flower buds (like artichokes). The dried flowers curdle milk. The leaves are also used medicinally and bees love the flowers. Likes a moist well drained soil and sun or light shade. Hardy to -10°C or so.
Globe artichoke. Tall perennial from Europe, growing 2 m (7 ft) high. Usually grown for the edible flower receptacles; also edible are the blanched leaves and stalks when cooked. The leaves are used medicinally and bees love the flowers. Likes a moist well-drained soil and sun; hardy to -15°C.
Purple coneflower. Perennial from the Eastern USA growing to 1.5 m (5 ft) high when flowering. The roots are now ell known for their medicinal properties - strengthening the immune system - and are widely used in herbal medicine. Likes a moist, well-drained soil and sun or part shade; hardy to -35°C. Protect from slugs!
Meadowsweet. European perennial growing to 2 m (7 ft) high when flowering. The leaves can be used for tea, the flowers for wine and the roots cooked and eaten; the aerial parts are medicinal, and all parts give dyes. A good mineral accumulator which attracts bees and beneficial insects. An essential oil from the plant is sometimes used in perfumery. Likes a part or fully shaded site and a moist soil; hardy to -30°C.
Russian liquorice. Perennial legume from Southern Europe, growing up to 1 m (3 ft) high. Sometimes cultivated as an annual. The roots are edible raw - they are the source of Russian and German liquorice. Also used medicinally, and a good ground cover. Deep rooted and an excellent mineral accumulator as well as fixing nitrogen. Likes a moist soil and part or full shade; hardy to -12°C. NB plants doesn’t start growing until late May or June - be patient!
Bush clover. A medium deciduous shrub from Eastern Asia, growing to 3 m (10 ft) high. A legume, fixing large amounts of nitrogen. The young leaves, stems, flowers and seeds are all edible when cooked, and the leaves are used as a tea substitute. Roots and leaves are used medicinally. Esteemed as a fodder plant (fresh or made into hay) and a good bee plant. Widely used for soil conservation and its wildlife value. Likes a well-drained soil in full sun; hardy to -23°C.
Lovage. A vigorous, deep-rooted, large perennial growing to 2 m (7 ft) high. All parts are strongly aromatic with a yeasty-celery flavour and make a good celery-substitute; the young stems and leaves are usually used (raw or cooked) but roots and seeds are also edible. Attractive to bees and hoverflies. Likes a moist soil and a position in sun or part shade; hardy to -25°C.
Bird’s foot trefoil. A nitrogen-fixing ground cover with masses of yellow flowers in summer. A bee plant, fodder plant, and has medicinal flowers. Likes sun and a well-drained soil; hardy to -20°C
Wild lupin. A perennial from North America, growing 60 cm (2 ft) high. The seeds are edible after cooking (used any way that cooked beans are); the young seedpods are also edible cooked. An excellent nitrogen-fixing legume which also accumulates other minerals. Leaves and flowering stems are used for dyeing and bees love the flowers. Likes a well-drained, slightly acid soil and full sun; hardy to -25°C.
Lemon balm. The familiar perennial herb with lemon-scented leaves which are excellent as a flavouring, in salads and teas. Planted thickly, it is a useful ground cover plant; it self-seeds readily and spreads quickly if allowed. Bees love the flowers. A good mineral accumulator. Tolerates most soils in a sunny or partly shaded position; hardy to -25°C.
Spearmint, Green mint. The familiar mint found in garden herb beds. It is a vigorous spreading perennial, growing to 1m (3 ft) high and forms a ground cover. Likes sun or part shade and a moist soil; hardy to -35°C. The leaves and essential oil are edible as a flavouring, medicinal, used in perfumery etc. Bees and butterflies love the flowers.
Watercress. Aquatic perennial which likes being by running water, but will grow in other damp sites. Grows to 50 cm (18”) high, and spreading twice that where it is comfortable, trailing and rooting as it goes; has small white flowers. You’ll know that the leaves are edible, with a strong peppery flavour. They are also medicinal, and bees love the flowers. Grow in any wet or damp soil; hardy to -20°C
Oregano, Pot marjoram. A bushy, woody-based perennial growing 45-60 cm (18-24”) high and wide, with dark green leaves and tiny mauve flowers in summer, much loved by bees. Likes a well-drained soil and sun or part shade. The leaves are used as a culinary herb, as is the essential oil from them. Also used medicinally, and for dyes. The plant is supposed to repel ants and other insects. Makes a good ground cover in sunny locations. Grow in any well drained soil in sun or part shade; hardy to -23°C.
Mountain sorrel. A perennial from Northern temperate regions, growing 50 cm high. The leaves are edible raw in salads, with an excellent lemony flavour and almost succulent texture. A dye is obtained from the flowers. Self-seeds readily. Likes a moist, slightly acid soil in sun or part shade; hardy to -40°C.
Ribwort plantain. Well known perennial plant found in pasture. The young leaves can be eaten raw or cooked; also used medicinally (similar uses to comfrey). The plants are good mineral accumulators and are a source of dyes. Any site in sun or part shade; hardy to -20°C.
Mountain mint. Perennial from the USA growing to 1.4 m (4½ ft) high when flowering. The leaves and flower buds are delightfully minty and used as a flavouring and to make teas. Bees like the flowers. Moist soils in sun or part shade; hardy to -25°C
An evergreen sorrel from Eastern Europe, growing to 1.2 m (4 ft) high when flowering. It has very nice edible leaves, larger than many sorrel species. Grows in any soil in sun or part shade, and will self-seed around the garden. Very hardy.
Soapwort. A perennial from Europe, growing 60 cm (2 ft) high, spreading more. As well as being a good ground cover plant (spreading vigorously), the leaves and roots contain saponins and can be used as soap sources: merely soak leaves/stems in warm/hot water, then use the soapy water to wash clothes etc. The flowers furnish dyes, whilst bees and butterflies feed on the nectar; the roots and flowering plant are also used medicinally. Likes a moist position in sun or part shade; hardy to -25°C.
Alexanders. A vigorous biennial of the umbellifer family, native to Europe and brought to Britain by the Romans, where it soon naturalised. Grows to 75-120 cm high in most soils. The young shoots, leaves, flower buds and roots are all edible, with a celery-like flavour; the seeds are peppery and can be ground as a condiment. Virtually evergreen over the winter and a very useful winter salad and cooking vegetable.
Tall ornamental red-feathered clover
10-20 inches tall. Drought tolerant
Nitrogen fixer. Bee plant.
I see that Agroforestry are sold out of actual plants till autumn, but many seeds are still available: see the online catalogue at:
Agroforestry Research Trust, 46 Hunters Moon, Dartington, Totnes, Devon, TQ9 6JT, U.K.
Wishing you a perennially Permaculture sowing season!