Phenomenal lavender

Sun

Full sun, with at least 6 hours of direct sunlight daily.

Water

Water regularly during establishment, allowing the soil to dry between waterings. Once established, water during prolonged dry spells; plants in containers need more frequent checks.

Soil

Lean, sharply drained sandy, gravelly or loamy soil, preferably neutral to alkaline. Avoid waterlogged ground and rich, heavily amended planting holes.

Height

2-3 ft (0.6-0.9 m), including flower stems

Spread

3-4 ft (0.9-1.2 m)

Flowers

Violet-purple flower spikes in early to midsummer, sometimes followed by a lighter flush after trimming.

Foliage

Evergreen. Narrow, aromatic, silver-grey leaves on a rounded woody framework; foliage may thin or suffer damage in cold winters.

Growth

Moderate; usually reaches its mature size in 2-3 years.

Care needed

Low

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

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

Difficulty

Easy

Toughness

Very tough

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

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   1.8 ft (0.55 m)

3. After 2 years

   2 ft (0.6 m)

4. After 3 years

   2.1 ft (0.65 m)

5. After 5 years

   2.5 ft (0.75 m)

   full size

About 5 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

Growth rate

Moderate

• Plant with the crown at soil level, preferably in spring where winters are cold.
• Allow enough space for its mature spread so air can move between plants.
• Water the root zone rather than wetting the foliage, and let the soil dry between waterings.
• Avoid routine feeding and rich compost; excess nitrogen encourages floppy growth.
• Use a thin gravel mulch if needed, keeping the crown clear of mulch and fallen leaves.
• Use a container with drainage holes and a gritty potting mix where garden soil stays wet.

Pruning. After the main flowering flush, remove spent stems and lightly shape the leafy growth. In spring, shorten untidy shoots while leaving green leaves below every cut; do not cut hard into bare old wood.

Spring

Check for winter damage and trim back to living, leafy growth once new shoots are visible.

Spring

Plant in a sunny, freely draining position and water thoroughly.

Early summer

Check newly planted shrubs during dry weather and water deeply when the root zone dries.

Midsummer

After the main flowers fade, remove spent stems and lightly shape the plant.

Autumn

Clear fallen leaves from the crown and avoid hard pruning before winter.

Winter

Check that water drains away from the roots; keep container drainage holes clear.

• Plant as a low informal hedge beside a sunny path, leaving room for its flowering stems to arch outward.
• Repeat rounded plants through a gravel garden with ornamental grasses and upright perennials.
• Combine with roses in an open, sunny border, keeping lavender outside heavily watered planting pockets.
• Use in large, well-drained containers beside seating where the scented foliage is within reach.

Garden styles it suits: Mediterranean, French country (Provençal), Cottage garden, Dry gravel garden, Pollinator garden and Sensory garden.

Plant it with: Catmint, Russian sage, Yarrow, Bearded iris, Lamb's ears and Upright stonecrop.

Wildlife: Flowers attract bees, butterflies and other nectar-feeding insects. Deer and rabbits usually avoid the aromatic foliage, though browsing is still possible.

• Root and crown rot: improve drainage, reduce watering and keep mulch away from the crown; replace badly affected plants.
• Winter dieback: avoid wet winter soil and autumn pruning; remove dead shoots in spring once live growth is clear.
• Woody, open growth: trim lightly each year without cutting into bare wood; replace old plants that no longer produce leafy growth near the base.
• Floppy stems and sparse flowering: provide full sun, stop nitrogen-rich feeding and avoid excessive irrigation.

Lavender contains linalool and linalyl acetate and is considered toxic to cats, dogs and horses if eaten. Leaves and flowers can cause digestive upset; concentrated essential oil poses a greater risk and should be kept away from pets. It is not generally considered poisonous to people in ordinary garden contact, although sap or fragrance may irritate sensitive skin; swallowing essential oil can be harmful.

• English lavender (Lavandula angustifolia)

  Usually has a smaller habit, shorter flower stems and earlier flowering; lavandin typically has taller, branched flowering stems.

• Grosso lavender (Lavandula × intermedia 'Grosso')

  Often has darker, thicker flower spikes, but its foliage and habit are very similar. Use a reliable plant label to confirm the cultivar.

• French or Spanish lavender (Lavandula stoechas)

  Has compact flower heads topped with conspicuous petal-like flags, rather than the long, slender spikes of Phenomenal.

The hybrid name intermedia means 'intermediate', reflecting its parentage between English lavender, Lavandula angustifolia, and spike lavender, Lavandula latifolia.

Propagation. Softwood or semi-ripe cuttings preserve the cultivar; this hybrid generally produces little or no viable seed. Phenomenal is a protected cultivar in some countries, so check current propagation rights before taking cuttings.

Accepted botanical name

Lavandula intermedia

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