Iris laevigata ‘Alboviolacea’

Iris laevigata ‘Alboviolacea’ (07/06/2014, Kew Gardens London)

Position: Full sun

Flowering period: Late spring to early summer

Soil: Wet, poorly drained

Eventual Height: 70cm

Eventual Spread: 70cm

Hardiness: 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b

Family: Iridaceae

Iris laevigata ‘Alboviolacea’ is a deciduous, erect, herbaceous perennial with a clump forming habit. Its mid green erect leaves are lanceolate with entire margins and gradually narrowing to a point, up to 90cm long and 1.5cm broad. Its white hermaphrodite flowers are up to 10cm across, emerge from a branched stem which emerges from the base of the leaf cluster. Its fruit is a loculicidal capsule. Its roots are rhizomes which allow this plant to spread slowly.

Iris laevigata ‘Alboviolacea’ Flower (07/06/2014, Kew Gardens London)

The species Iris laevigata, commonly known as Japanese Iris or Smooth Iris, is native to temperate Asia. In its native habitat it grows on the banks of ponds and along stream banks.

The etymological root of the binomial name Iris is derived from the Greek word for a rainbow, referring to the wide variety of flower colours found among the many species. Laevigata is derived from the Latin meaning ‘smooth’.

The landscape architect may find Iris laevigata ‘Alboviolacea’ useful as an effective spreading ground cover marginal plant with attractive flowers suitable for planting at the the edges of water bodies.

Iris laevigata ‘Alboviolacea’ Leaf (07/06/2014, Kew Gardens London)

Ecologically, Iris laevigata ‘Alboviolacea’ flowers are attractive to pollinating insects.

Iris laevigata ‘Alboviolacea’ prefers waterlogged, humus rich, poorly drained soils. It prefers a neutral to acid pH of soil. Its preferred planting depth in water is 0cm to 15cm.

Iris laevigata ‘Alboviolacea’ requires little maintenance. Large clumps may be divided in mid summer to early autumn.

Tradescantia x andersoniana ‘Sweet Kate’

Tradescantia x andersoniana ‘Sweet Kate’ (21/09/2013, Kew Gardens, London)

Position: Full sun to partial shade

Soil: Moist, well drained

Flowering period: Summer to early autumn

Eventual Height: 60cm

Eventual Spread: 30cm

Hardiness: 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b

Family: Commelinaceae

Tradescantia x andersoniana ‘Sweet Kate’ is a herbaceous perennial with a grass-like tufted habit.  It yellow green leaves are strap like with entire margins, with parallel venation and a centre groove held on tubular stems. Its blue/ purple flowers have contrasting yellow stamens and are composed of three petals. Each flower will only bloom for a single day. Its root are rhizomes which aids its spread.

Tradescantia x andersoniana, commonly known as Spiderwort, is likely to be a cross between Tradescantia ohioensis, Tradescantia subspera and Tradescantia virginiana. This plant may be invasive given the right  conditions.

The etymological root of the binomial name Tradescantia is named after John Tradescant (1608-1662) who served as gardener to Charles 1 of England. Andersoniana is named after Edgar Anderson (1897 – 1969), an American botanist.

The landscape architect may Tradescantia x andersoniana ‘Sweet Kate’ is useful as a low maintenance perennial tolerant shady locations with a long flowering period. It also naturalises effectively and is suitable for ground-cover in woodland schemes.

Tradescantia x andersoniana ‘Sweet Kate’ Flower (21/09/2013, Kew Gardens, London)

Ecologically,  Tradescantia x andersoniana ‘Sweet Kate’ flowers are attractive to pollinating insects.

Tradescantia virginiana prefers moist, fertile, well-drained soils. It tolerates most pH of soil, although it prefers an acidic pH of soil. It will tolerate wet soils.

Tradescantia virginiana requires little to no care. To keep a tidy appearance this plant may be cut to ground level once flowering is complete in early winter. Large clumps may be divided in autumn to increase plant numbers.

Landscape Architecture

Panicum virgatum ‘Heavy Metal’

Panicum virgatum ‘Heavy Metal’ (21/09/2013, Kew Gardens, London)

Position: Full sun to partial shade

Flowering period: late summer to early autumn

Soil: Moist, well drained

Eventual Height: 1m

Eventual Spread: 1m

Hardiness: 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b

Family: Poaceae

Panicum virgatum ‘Heavy Metal’ is an upright, clump forming grass. Its blue/ green leaves are strap like. In autumn its leaves turn a yellow colour. Its purple/ green flowers are finely textured and appear above the leaves. These turn beige by late autumn an are retained on the plant during the winter months. its roots are deep and fibrous and it produces rhizomes which may aid its spread.

The species Panicum virgatum, commonly known as Switchgrass, Tall Panic Grass, Blackbent, Wild Redtop and Virginia Switchgrass, is native to North America. In its native habitat it is the dominant species of the North American tall grass  prairie.

The etymological root of the binomial name Panicum is the ancient Latin name for Italian Millet. Virgatum is from the Latin meaning ‘made of twigs striped’.

Panicum virgatum ‘Heavy Metal’ Flower (21/09/2013, Kew Gardens, London)

The landscape architect may find Panicum virgatum ‘Heavy Metal’ useful in a wide variety of situations due to its tolerance of wet to dry soils. It is suitable for low maintenance prairie type planting schemes. It is also suitable for use in SUDS schemes and rain gardens. It looks fantastic when planted en mass. Due to  its deep roots it is also useful for soil stabilisation. Once established this grass is drought tolerant.

Ecologically, Panicum virgatum ‘Heavy Metal’ seed is attractive to some birds.

Panicum virgatum ‘Heavy Metal’ prefers moist, fertile, well-drained soils. It tolerates most pH of soil. It will tolerate wet soils for short periods of time.

Panicum virgatum ‘Heavy Metal’ requires little maintenance. It may be cut to near ground level in early spring to provide a tidy appearance. Large clumps may be divided from mid spring to mid summer.