Iris 'Sierra Blue' (TB) — Clump forming

Overview

Iris 'Sierra Blue' (TB) is a clump forming herbaceous perennial in the genus Iris, part of the Iridaceae family, with deciduous foliage. Iris 'Sierra Blue' (TB) grows best in full sun, and tolerates loam soils and neutral pH. Its UK hardiness is rated H6. Suggested uses include city and courtyard gardens, cottage and informal garden, patio and container plants, cut flowers and flower borders and beds.

About

Iris 'Sierra Blue' is a clump-forming herbaceous perennial in the Iridaceae that flowers from May to July. It carries deciduous foliage and performs best in a sunny, sheltered position on well-drained neutral loam. Plant where the aspect is south-, east- or west-facing to get the most reliable bloom. It suits borders, containers and cutting for vases.

About the genus

Iris takes its name from the Greek goddess of the rainbow, and for once the naming feels entirely earned. I can't think of another genus that covers so much ground — inky purples, burnt apricots, clean whites, blues that seem lit from inside — or so many situations. There are bearded irises that want their rhizomes baked in full sun, Siberian types happy in ordinary border soil, and species that will sit contentedly at the edge of a pond. What they share is the flower: three petals standing up, three falling away, built with a kind of architectural confidence most plants never attempt. Even out of bloom the foliage earns its place — those upright fans of blue-green leaves hold a border together for months. I grow them for the fortnight in May and June when nothing else in the garden can compete, and I've made my peace with that. Some plants are for the long haul. An iris is an event.

Written by Henry

In the garden

Iris 'Sierra Blue' sits within the Iridaceae as a clump-forming herbaceous perennial with deciduous leaves and a defined flowering season of May to July. Where it comes from is not provided here, but its cultural needs are clear: a sunny, sheltered site and a soil that is loam-based, neutral in pH and drains freely. Choose a south-, east- or west-facing aspect so the plant receives full sun through much of the day; avoid exposed, windy spots since a sheltered exposure helps preserve the flower spikes. H6 hardiness indicates the cultivar is very hardy in UK conditions, so once established it will tolerate winter conditions typical of most gardens while the foliage dies back in the dormant season. Plant into well-drained loam and do not allow the crown to sit in waterlogged soil. The clump-forming habit makes it straightforward to position in flower borders and beds, or in containers on patios and courtyards where drainage can be controlled. Flower stems produced from May to July are suitable for cutting, making it effective both as a border plant and as a source of vase flowers in a cottage or informal planting scheme.

Growing conditions

Best soil and position for Iris

Sunlight: Full sun
Soil type: Loam
Soil pH: Neutral
Soil moisture: Well-drained
Aspect: South-facing, East-facing, West-facing
Exposure: Sheltered
UK hardiness: H6

Plant details

Iris 'Sierra Blue' (TB) size, habit and characteristics

Plant type: Herbaceous Perennial
Habit: Clump forming
Foliage: Deciduous
Suggested uses: City and courtyard gardens, Cottage and informal garden, Patio and container plants, Cut flowers, Flower borders and beds