Upright myrtle spurge

Sun

Full sun; tolerates light shade but grows less compactly.

Water

Low once established. Water new plants during dry spells; established plants usually need extra water only during prolonged drought.

Soil

Well-drained sandy, gravelly or stony soil, including alkaline soil. Avoid heavy soil that stays wet in winter.

Height

1-2 ft (0.3-0.6 m)

Spread

2-3 ft (0.6-0.9 m)

Flowers

Late winter to spring; tiny yellow flowers surrounded by conspicuous lime-yellow bracts.

Foliage

Evergreen. Thick, pointed, blue-grey leaves arranged in close spirals around upright to outward-arching stems.

Growth

Moderate

Care needed

Low

• Pollinators
• Deer resistant
• Drought tolerant
• Heat tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.1 ft (0.35 m)

3. After 2 years

   1.3 ft (0.4 m)

4. After 3 years

   1.5 ft (0.45 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Plant with the crown clear of standing water; use a raised bed if drainage is poor.
• Water deeply during establishment, allowing the soil to dry between waterings.
• Avoid routine feeding; rich soil encourages soft, sprawling growth.
• Use gravel mulch rather than moisture-holding mulch against the stems.
• Remove unwanted seedlings while small, wearing gloves.
• Wear gloves, long sleeves and eye protection whenever cutting or handling damaged stems.

Pruning. After flowering, cut spent flowering stems back near the base, leaving fresh non-flowering shoots intact. Remove the heads before seed ripens if you want to limit self-seeding, and avoid getting the milky sap on skin or in eyes.

Spring

Plant in freely draining soil once severe frost has passed.

Late spring

Cut out finished flowering stems before seed capsules ripen, keeping new shoots.

Summer

Water young plants during dry spells; let established plants dry between waterings.

Autumn

Remove unwanted seedlings and clear fallen leaves away from the crown.

Winter

Check that water drains freely around the plant; avoid watering wet or frozen soil.

• Plant in a gravel garden with lavender and rock roses for contrasting silver foliage and spring colour.
• Repeat small groups along a sunny border to create a rhythm of sculptural, blue-grey foliage.
• Place among rocks on a dry slope, where its arching stems soften hard edges.
• Combine with dark-leaved stonecrops and fine-textured grasses in a drought-tolerant border.

Garden styles it suits: Mediterranean, Dry gravel garden, Desert / xeriscape, Architectural minimal, Modern Mediterranean and Low-maintenance.

Plant it with: Lavender, Rock rose, Santolina, Bearded iris, Blue fescue and Autumn stonecrop.

Wildlife: The accessible flowers attract bees, hoverflies and other small insects in late winter and spring. Deer and rabbits usually leave the foliage alone.

• Root and crown rot in wet soil: improve drainage or move the plant to a raised, gravelly position.
• Winter damage in cold, exposed sites: choose a sheltered, sunny spot and keep the crown dry.
• Aphids on soft growth: dislodge with water or remove badly affected shoots while wearing protective clothing.
• Unwanted seedlings: remove flower heads before seed ripens and pull seedlings promptly.

Toxic to people, cats, dogs and horses if eaten. All parts contain irritating milky latex that can cause mouth irritation, vomiting and diarrhoea; skin contact can cause dermatitis, and eye exposure can cause severe injury. Keep away from children and pets, and seek urgent medical advice for sap in the eyes.

Where it spreads. Can self-seed freely and escape cultivation in California and other dry, mild-winter regions. Check local weed guidance before planting; it is distinct from myrtle spurge (Euphorbia myrsinites), which is regulated in parts of the western United States.

• Myrtle spurge (Euphorbia myrsinites)

  Has lower, trailing stems and broader, more rounded blue-grey leaves; upright myrtle spurge has taller stems and narrower, sharply pointed leaves.

• Mediterranean spurge (Euphorbia characias)

  Usually grows much taller, with narrow leaves crowded toward the stem tips and large, elongated flower heads.

• Caper spurge (Euphorbia lathyris)

  Has long, narrow leaves arranged in opposite pairs along tall stems, rather than thick leaves spiralling closely around the stems.

The species name rigida means stiff or rigid, referring to the plant's firm, upright growth.

Propagation. Grow from seed or take basal shoot cuttings in spring using gloves and eye protection. Seedlings may appear around established plants; move them while small, taking care not to damage the roots.

Accepted botanical name

Euphorbia rigida

In the US and Canada

Introduced in the lower 48 states.

Native range

Albania, Algeria, East Aegean Is., Greece, Iran, Kriti, Krym, Lebanon-Syria, Morocco, North Caucasus, Romania and Sicilia.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.