Goat’s-rue

How to recognise it

Habit

Perennial in a loose clump 0.6–1.5 m tall, with many upright, branched stems.

Leaf

Pinnate, with 9–17 lance-shaped leaflets of 1.5–5 cm tipped with a tiny bristle point; two arrow-shaped stipules at the base.

Flower

Upright, long-stalked spikes of 5–15 cm with pea flowers of about 1 cm, white, lilac or bluish lilac, from June to September.

Fruit/Seed

Narrow, cylindrical pods of 2–5 cm, straight and slightly constricted between the seeds; brown when ripe.

Stem

Hollow, hairless and grooved; slightly woody at the base.

Look-alikes

Vetches have tendrils at the leaf tip and climb; goat’s-rue stands upright and has no tendrils. Crown vetch has pink and white flowers in round heads. Wild liquorice has creamy yellow flowers and sprawls more over the ground.

Flowering: June–September · Pruning: March and August

Why grow it?

• Flowers for three months, with plenty of nectar and pollen for honeybees, bumblebees and solitary bees.
• Like other members of the pea family, it fixes nitrogen from the air in nodules on its roots.
• A sturdy, airy plant for the back of a natural border or a rough corner on moist soil.
• Its hollow stems, left standing over winter, give shelter to insects.
• A historic plant: once grown as livestock fodder because people believed it increased milk yield.

Goat’s-rue: where does it grow best?

• In the wild on riverbanks, railway embankments, waste ground and rough, damp verges.
• Full sun to light partial shade; it flowers most freely in sun.
• Fertile, moisture-retentive soil: loam or clay, also slightly chalky; it tolerates short wet spells.
• Allow 60–80 cm per plant; it forms a sizeable clump with a deep root.
• Not in or next to a pasture with sheep, horses or other livestock, and preferably not right beside a stream, where it easily seeds itself further.

Goes well with

• Purple loosestrife: Purple spikes on the same moist soil, for bees and butterflies.
• Hemp-agrimony: Flowers in late summer and attracts many butterflies.
• Meadowsweet: Creamy white, fragrant plumes in the same moist border.
• Wild carrot: White umbels for hoverflies and small beetles, contrasting with the spikes.

Goat’s-rue: when and how to plant it?

1. Buy a plant from a perennial nursery, or sow it yourself; never dig up plants from the wild.
2. Sow in March–April: soak the hard seed overnight in lukewarm water and sow in small pots, 1 cm deep. It germinates in 2–3 weeks.
3. Plant out in May, or plant bought plants in April–May or September–October, 60–80 cm apart.
4. Choose the final spot straight away: because of its deep taproot it does not transplant well.
5. Water during dry spells for the first few weeks; after that it looks after itself.
6. Put in a plant support or a few canes when planting: after rain the clump easily flops open.

Care

Watering

Only in the first year during drought. After that only in long dry spells.

Feeding

Not needed: it takes nitrogen from the air itself. Fertiliser makes it floppy.

Support

A ring or a few canes in May keep the clump together.

Spreading

It self-seeds freely. Cut off the faded spikes before the pods ripen and pull up unwanted seedlings while young, roots and all.

Faded spikes

Cutting them off after the first flush often gives a second, smaller flowering.

Tip: Cut the flower spikes back after the first flush: this stops it seeding everywhere and often gives you a second flowering in September.

Pruning and mowing

Pruning months: March and August.

When: Faded spikes in August, before the seed ripens. The old stems in March, before the new shoots appear.

How:

• In August, cut the faded spikes back to above a healthy leaf so that no seed drops.
• Leave the hollow stems standing over winter as shelter for insects.
• In March, cut all the old stems back to 5–10 cm above the ground.
• Wear gloves and do not put the cuttings in a pasture or near animals.

Caution: Never give prunings or cuttings to rabbits, guinea pigs, sheep or other livestock: it stays poisonous even when dried.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

In March–April in small pots, after soaking overnight in lukewarm water. Seedlings often flower in their second year.

Division

Young clumps can be carefully split with a sharp spade in March; older plants with a deep taproot do not tolerate this well.

Goat’s-rue: how does it get through the winter?

Hardy to −25 °C.

• Dies back above ground in autumn and reshoots from the rootstock in spring.
• Fully hardy, to about −25 °C.
• Leave the hollow stems until March: insects overwinter in them and birds find shelter.

Diseases and pests

• Self-seeding: Seedlings appear everywhere nearby. Cut off faded spikes in time and pull up seedlings while young.
• Flopping: After rain or wind the clump falls open. Put in a support in May and choose a sunny spot on soil that is not too rich.
• Powdery mildew: White powder on the leaves in late summer. Harmless; give it space and cut back affected stems after flowering.
• Poisonous to animals: Dangerous to livestock and rodents. Do not plant it where animals graze and never feed cuttings.

Through the year

• March: Cut back the old stems. Sow in pots.
• April: New shoots. Plant or plant out.
• May: Put in plant supports. Plant out seedlings.
• June: Start of flowering: bees and bumblebees.
• July: Full flower. Water during long droughts.
• August: Cut off faded spikes before the seed ripens.
• September: Last flowers. Planting is possible.
• October: Plant. The plant dies back above ground.
• November: Leave the hollow stems standing for insects.

Did you know?

• The name Galega comes from the Greek gala, ‘milk’: people used to believe the plant increased the milk yield of cows and goats.
• A substance called galegine was extracted from goat’s-rue. Research on it led, in the twentieth century, to the development of a well-known medicine; the plant itself is poisonous.
• Goat’s-rue works with a soil bacterium of its own, which forms the root nodules where nitrogen is fixed only on Galega species.