Innthal

Euphorbia

Variety Description

Varieties used for comparison: 'Imprefant' (Improved Efanthia) and 'Purpurea' (Purple Wood Spurge)

Summary: 'Innthal' has taller plants than 'Purpurea' and narrower leaves than both reference varieties. The stems of 'Innthal' are light green with absent to very weak anthocyanin colouration while those of 'Imprefant' are light green and red with moderate anthcyanin on the upper part of the stems and those of 'Purpurea' are red with strong anthocyanin. 'Innthal' has denser pubescence of the stem and the upper and lower sides of the leaf blade than 'Purpurea'. The upper side of the leaf blade is light green for 'Innthal' while it is darker green for 'Imprefant' and darker blue green for 'Purpurea'. During the autumn season, 'Innthal' has weaker anthocyanin colouration than either reference variety on both the upper and lower sides of newly opened leaves or leaves located in the upper parts of the plant.

Description:

'Innthal' is a vegetatively propagated, tender perennial Euphorbia variety with upright bushy plant growth habit. The plants have a moderate degree of branching. The stems are medium to thick and smooth with dense pubescence. They are light green with absent to very weak anthocyanin colouration.

The leaves of 'Innthal' are simple and distributed in a whorled or alternate arrangement along the stem. The leaf blade ranges from elliptic to oblanceolate in shape with an acute apex, attenuate base and entire margin. Pubescence of the leaf blade is moderate on the upper side and dense on the lower side. The upper side of the leaf blade is medium green and glaucosity is present. The lower side of the leaf blade is light green with weak anthocyanin on newly opened leaves and leaves in the upper parts of the plant. There is a petiole present.

In autumn, the main colour of the leaf blade is dark green on the upper side and brown on the lower side. Also at this time, the upper and lower sides of leaves that are newly opened or located in the upper parts of the plant have weak anthocyanin colouration.

Origin & Breeding History: 'Innthal' originated form a cross conducted in the spring of 1998 between the female parent, Euphorbia amygdaloides L. 'Purpurea' and the male parent, Euphorbia characias L. ssp. wulfenii (Hoppe & Koch) Rad. This cross was part of a breeding program at InnovaPlant GmbH & Co. KG, in Gensingen, Germany with the objective of developing new, compact Euphorbia varieties with interesting foliage and flower characteristics which are adaptable to container planting. 'Innthal' was selected in September of 1999 based on its compact plant habit and flowering characteristics.

Tests & Trials: The test and trial for 'Innthal' was conducted in a polyhouse at BioFlora Inc. in St. Thomas, Ontario during the summer of 2005. The trial included 15 plants of the each variety. All plants were grown from rooted cuttings and transplanted into 6 inch pots on June 15, 2005. All colour characteristics were determined using the 2001 Royal Horticultural Society (RHS) colour chart and measured characteristics were based on ten measurements.

Comparison tables for 'Innthal' with reference varieties 'Imprefant' and 'Purpurea'

Plant height (cm)

Leaf blade width (cm)

Colour of upper side of leaf blade (RHS)

Colour of lower side of leaf blade (RHS)

Colour of upper side of leaf blade in autumn (RHS)

Colour of lower side of leaf blade in autumn (RHS)

Click on image for larger view

Euphorbia: 'Innthal' (left) and 'Imprefant' (centre) with reference variety 'Purpurea' (right)