Blue Fortune hyssop

Sun

Full sun; tolerates light shade but flowers less freely and may lean.

Water

Water regularly during establishment. Once established, water during prolonged dry spells; avoid persistently wet soil.

Soil

Well-drained soil of average fertility, from slightly acidic to slightly alkaline. Avoid heavy, waterlogged clay, particularly in winter.

Height

2-3 ft (0.6-0.9 m)

Spread

1.5-2 ft (0.45-0.6 m)

Flowers

Midsummer to early autumn; dense spikes of small lavender-blue flowers.

Foliage

Green, toothed, broadly lance-shaped leaves with an anise or liquorice scent when rubbed; stems and leaves die back in winter.

Growth

Moderate to fast; usually flowers well in its first growing season.

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

Fairly tough

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

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.6 ft (0.49 m)

3. After 2 years

   2.2 ft (0.68 m)

4. After 3 years

   2.5 ft (0.75 m)

   full size

About 2 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

Safe

Growth rate

Fast

• Plant in spring in colder or winter-wet areas so roots establish before winter.
• Water deeply during the first growing season, allowing the surface soil to dry between waterings.
• Apply a thin layer of compost in spring; avoid heavy feeding, which encourages floppy growth.
• Keep mulch away from the crown, and improve drainage before planting if water collects there.
• Divide healthy clumps in spring every few years if flowering declines or the centre becomes sparse.

Pruning. Leave the stems standing through winter, then cut them back to just above emerging basal growth in early spring. During summer, remove spent flower spikes if you want a tidier appearance and some additional flowering.

Early spring

Cut down old stems once new growth appears; check the crown for winter damage.

Spring

Plant or divide clumps, water them in thoroughly, and add a light dressing of compost.

Late spring

Take softwood cuttings from healthy, non-flowering shoots.

Summer

Water young plants during dry weather and remove spent spikes if desired.

Early autumn

Leave some flower heads standing for structure and reduce watering as growth slows.

Winter

Keep the crown free of soggy leaves and check that surrounding soil drains freely.

• Plant repeated groups through a sunny mixed border to create a rhythm of upright blue flower spikes.
• Combine with coneflowers, black-eyed Susans and ornamental grasses for a long-flowering perennial planting.
• Use beside a path or seating area where you can enjoy the scented foliage without blocking access.
• Add to a sunny pollinator border with plants that flower earlier and later to extend the feeding season.

Garden styles it suits: Cottage garden, New perennial (prairie), Pollinator garden, Wildlife garden, Sensory garden and Blues and silvers.

Plant it with: Purple coneflower, Black-eyed Susan, Switchgrass, Meadow sage, Yarrow and Stonecrop.

Wildlife: Flowers attract bees, butterflies and other nectar-feeding insects. Deer and rabbits often leave the aromatic foliage alone, although browsing is still possible.

• Crown and root rot in wet soil: improve drainage or move the plant to a raised position; avoid wet mulch against the crown.
• Powdery mildew: give plants full sun and adequate spacing, and water the soil rather than the leaves.
• Slugs and snails on emerging shoots: inspect young growth and use barriers, hand-picking or an approved iron-based bait.
• Flopping stems in shade or rich soil: move to a sunnier position, reduce feeding and provide discreet support if needed.

Not known to be toxic to people, cats, dogs or horses. No poisonous part is established, although information specific to this cultivar is limited; do not assume an ornamental nursery plant is suitable for eating.

• Catmint (Nepeta × faassenii)

  Catmint usually forms a lower, spreading mound with smaller grey-green leaves and looser flower sprays; Blue Fortune has taller upright stems, larger green leaves and denser spikes.

• English lavender (Lavandula angustifolia)

  Lavender has narrow grey-green leaves and a persistent woody framework; Blue Fortune has broad, toothed green leaves and dies back to the ground in winter.

Agastache comes from Greek words meaning 'many' and 'ear of grain', referring to the numerous flower spikes.

Propagation. Divide established clumps in spring or take softwood cuttings in late spring. This hybrid is generally sterile and is propagated vegetatively to preserve the cultivar; seed is not a reliable way to produce 'Blue Fortune'.

Accepted botanical name

Agastache

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