Myrtle spurge

Myrtle spurge: how do you recognise it?

Habit

Trailing to ascending stems 20–40 cm long, together forming a low, spreading plant about 15 cm tall and 40 cm wide.

Leaves

Fleshy, blue-grey and bloomy, pointed oval, arranged in a spiral around the stem; evergreen.

Flower

Heads of small flowers with sulphur-yellow to lime-green bracts at the stem tips, from March to May.

Sap

White, strongly irritant milky sap in all parts.

Seed

Seed capsules that burst open when ripe and shoot out the seeds; it self-seeds easily.

Roots

A sturdy taproot; large plants do not transplant well.

Flowering: March–May · Plants: March–April and September · Pruning: June

Why grow it?

• Elegant blue-grey leaves all year round, even in winter.
• Sulphur-yellow bracts in early spring, when little else is in flower; bees visit the small flowers.
• Extremely drought tolerant: perfect for gravel, rock gardens, walls and sunny pots.
• Rabbits and slugs usually leave it alone.
• Low and spreading: a pretty edging at the front of a sunny border or over a wall.

Myrtle spurge: where does it grow best?

• Full sun: in shade the stems become long and floppy and the leaves lose their blue colour.
• Poor, free-draining soil: sand or loam with grit, acid to chalky. Wet soil in winter is fatal.
• A dry spot: a rock garden, a gravel bed, the top of a wall or a sunny bank.
• Plant 30–40 cm apart, preferably on an edge so the stems can trail down.

Light

Sun

Soil type

Sand or loam

Acidity

Not fussy

Moisture

Dry

Size

0.15 m tall, 0.4 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Houseleek: Also evergreen and drought tolerant, for a rock garden or wall top.
• Thyme: Low, fragrant cushions that flower after the spurge.
• Species tulip: Small tulips that flower in April among the blue-grey leaves.
• Aubrieta: Purple cushions at the same time, lovely beside the yellow.
• Rock rose: Flowers in early summer, when the spurge has finished.

Myrtle spurge: when and how to plant it?

Plant in March–April and September.

1. Plant in March–April or in September, so the roots can establish before summer or winter.
2. Wear gloves: every broken leaf releases sap.
3. On heavier soil, mix plenty of grit or coarse sand into the soil; do not add compost.
4. Set the plant at the same depth as it was in the pot, or slightly higher, so the crown does not sit in wet soil.
5. Leave 30–40 cm between plants.
6. Water moderately after planting and spread a thin layer of gravel around the base.

Care

Water

Hardly ever once established; in a pot, only when the compost is completely dry.

Feeding

Not needed: in rich soil it becomes floppy and less blue.

Spent stems

Cut them off at the base after flowering: this prevents seedlings and keeps the plant compact.

Seedlings

Pull out unwanted seedlings while they are young, wearing gloves.

Clear base

Remove fallen leaves of other plants from around the base so it does not rot in winter.

Pot

Use a pot with a good drainage hole and a mix of compost with plenty of grit.

Tip: In June, cut the spent stems off at the base before the seed capsules burst: the plant stays compact and you get far fewer seedlings.

Myrtle spurge: when to prune it?

Pruning months: June.

When: After flowering, in June, cut the stems that have flowered off at the base. This year’s young stems will flower next spring.

How:

• Cut away only the spent stems, as low as possible, and leave the young, non-flowering stems.
• Wear gloves and long sleeves, and keep your hands away from your face.
• Do it before the seed capsules burst: it will self-seed far less.
• Remove dead or brown stems as soon as you see them.

Caution: The sap is strongly irritant to the skin and eyes. Wear gloves and preferably safety glasses, and rinse at once with plenty of water if you get any on you.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seedlings

It self-seeds. Move young seedlings in spring while they are small and the taproot is not yet too deep.

Cuttings

In June: cut a young, non-flowering stem of 5–8 cm, dip the cut end in lukewarm water to stop the sap, let it dry for a day and insert it in gritty cutting compost.

Myrtle spurge: how does it get through the winter?

Hardy to −25 °C.

• Hardy to about −25 °C: cold is no problem, wet feet are.
• Evergreen: the blue-grey leaves stay attractive all winter.
• In heavy, wet soil it rots in winter. A raised spot or a layer of gravel helps.
• In a pot: leave it outdoors, but keep it dry in winter, for example under a roof overhang.

Diseases and pests

• Root rot: The plant turns soft and brown after a wet winter. Plant in gravel or on a raised spot and do not give extra water.
• Seedlings: It self-seeds freely into gravel and paving joints. Cut off spent stems in time and weed out seedlings young.
• Floppy growth: In shade or rich soil the stems become long and the leaves greener. Move it to a sunny, poor spot.
• Skin irritation: Redness, itching or blisters after contact with the sap. Rinse at once with plenty of water and wear gloves from now on.

Through the year

• March: Flowering begins. Plant.
• April: Full flower. Plant. Move seedlings.
• May: Last flowers. Bees on the small flowers.
• June: Cut spent stems off at the base, wearing gloves. Take cuttings.
• July: Weed out seedlings. No watering needed.
• September: Plant.
• November: Remove fallen leaves around the base to prevent rot.
• December: The blue-grey leaves brighten the rock garden.

Edible and useful

Not edible. All parts of spurges contain a white, milky sap that is poisonous and caustic. On the skin it causes redness, itching and sometimes blisters; in the eyes it is extremely painful and can damage the cornea. Whenever you work on the plant, wear gloves, long sleeves and ideally safety glasses, do not rub your eyes, wash your hands and secateurs afterwards, and teach children not to break off the stems. If sap gets in your eyes, rinse them at once under running lukewarm water for at least a quarter of an hour and see a doctor. Swallowed, it burns the mouth and causes vomiting and stomach ache, in dogs and cats too; horses and livestock fall ill from it: never throw clippings into a field. If any is swallowed, call a poison centre (in Belgium 070 245 245) or your doctor at once.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The species name myrsinites means ‘like myrtle’ and refers to the shape of the leaves.
• In English it is also called donkey tail spurge, after its thick, scaly-looking stems.
• Ripe seed capsules burst open and shoot out the seeds, so seedlings also pop up some distance from the plant.