Iris spuria 'A. W. Tait' (Blue Iris) — Clump-forming, upright

Overview

Iris spuria 'A. W. Tait' is a clump-forming, upright perennial in the genus Iris, part of the Iridaceae family, with deciduous or evergreen; sword-shaped to grassy, often glaucous foliage. Iris spuria 'A. W. Tait' grows best in full sun; some tolerate partial shade, and tolerates loam and chalk or sand; sharply drained for bearded kinds soils and neutral to slightly alkaline pH. Its UK hardiness is rated H5–H7.

About

Iris spuria 'A. W. Tait' is a clump-forming, upright perennial in the iris family, notable for its purple to lilac flowers. The foliage is sword-shaped to grassy and often has a glaucous, blue-green cast; leaves may be deciduous or retain through the season. It performs best in full sun on a south- or west-facing site but will tolerate some light shade and both exposed and sheltered conditions.

Wikipedia contributors, CC BY-SA 4.0 — Iris spuria

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 spuria 'A. W. Tait' belongs to the spuria group of irises and is grown for its upright clumps and long, sword-like leaves. Plants of this group are common in gardens and show well as architectural perennial clumps. Flowering takes place from May to July, producing purple to lilac blooms that sit above the foliage. Choose a site in full sun, ideally on a south- or west-facing aspect; the plant will also tolerate some partial shade and exposed positions. Soil should be free-draining loam, chalk or sand on a neutral to slightly alkaline pH. Avoid waterlogged ground; spuria irises prefer well-drained conditions, though related groups such as Siberian and Japanese irises favour more moisture-retentive soil. Hardiness H5–H7 indicates this iris ranges from hardy to fully hardy across much of the UK, so it suits many garden situations where winter protection is not required. Use it in perennial borders, gravel beds or other sunny schemes where upright clumps can provide vertical structure. Expect the main display to run from May to July.

Growing conditions

Best soil and position for Iris

Sunlight: Full sun; some tolerate partial shade
Soil type: Loam, chalk or sand; sharply drained for bearded kinds
Soil pH: Neutral to slightly alkaline
Soil moisture: Well drained; Siberian and Japanese kinds need moisture-retentive soil
Aspect: South or west facing
Exposure: Exposed or sheltered
UK hardiness: H5–H7

Plant details

Iris spuria 'A. W. Tait' size, habit and characteristics

Plant type: Perennial
Habit: Clump-forming, upright
Foliage: Deciduous or evergreen; sword-shaped to grassy, often glaucous

Care notes

Pruning and caring for Iris spuria 'A. W. Tait'

Cultivation: Plant bearded irises with the top of the rhizome exposed so it can bake in summer sun; beardless kinds sit just below the surface in richer, damper ground. Feed with a low-nitrogen fertiliser after flowering and keep the rhizomes clear of mulch and encroaching neighbours.
Pruning: Remove spent flower stems at the base. Trim the outer leaves back by about half in late autumn to reduce overwintering fungal spores, leaving the central fan intact.
Propagation: Divide rhizomes six to eight weeks after flowering, discarding the old woody centre and replanting vigorous outer sections. Species come from seed, but named cultivars will not come true.
Pest resistance: Generally trouble-free, though iris sawfly and slugs damage foliage and thrips can disfigure buds.
Disease resistance: Prone to leaf spot, and to rhizome rot wherever drainage is poor or planting too deep.

Frequently asked questions

How do I grow Iris spuria 'A. W. Tait'?

Plant bearded irises with the top of the rhizome exposed so it can bake in summer sun; beardless kinds sit just below the surface in richer, damper ground. Feed with a low-nitrogen fertiliser after flowering and keep the rhizomes clear of mulch and encroaching neighbours.

Where is the best place to plant Iris spuria 'A. W. Tait'?

Iris spuria 'A. W. Tait' prefers full sun; some tolerate partial shade. It suits exposed or sheltered positions.

What soil does Iris spuria 'A. W. Tait' need?

Iris spuria 'A. W. Tait' grows best in loam and chalk or sand; sharply drained for bearded kinds soil. It prefers neutral to slightly alkaline soil. Aim for soil that stays well drained; siberian and japanese kinds need moisture-retentive soil.

How do I prune Iris spuria 'A. W. Tait'?

Remove spent flower stems at the base. Trim the outer leaves back by about half in late autumn to reduce overwintering fungal spores, leaving the central fan intact.

Is Iris spuria 'A. W. Tait' hardy in the UK?

Iris spuria 'A. W. Tait' has an RHS hardiness rating of H5, meaning it is hardy in most of the UK, tolerating -15 to -10°C.

How do I propagate Iris spuria 'A. W. Tait'?

Divide rhizomes six to eight weeks after flowering, discarding the old woody centre and replanting vigorous outer sections. Species come from seed, but named cultivars will not come true.

More in the Iris genus

Browse all Iris →