Pieris – Andromedas.
Family Ericaceae.
Known commonly as Andromedas they are sometimes seen under that genus name.
There are seven species, a number of hybrids and over 40 cultivars.
Some are used in gardens or for cut flowers.
They are evergreen shrubs up to 6 metres tall and almost as wide.
Leaves are spirally arranged but close so may appear to be in whorls.
They are on stalks.
The blades are ovate to lance shaped up to 10 cm long and nearly 4 cm wide.
The edge may be smooth or serrated.
In spring the young leaves are a red or copper colour.
Inflorescences are terminal or axillary with many drooping flowers.
Flowers are on stalks that may or may not have hairs with glands.
Flower parts are in 5’s.
The 5 sepals have small glands on the outer surface and hairs inside.
The 5 petals are fused for most of their length with small terminal lobes.
They may be tubular or urn-shaped with a constriction just below the lobes.
They are 5 to 15 mm long and white or pink.
There are 10 stamens with white filaments that are wider at the base and have short hairs.
The anthers open via oval pores either inwards or at the top.
There are 2 long appendages from the base of each anther.
The ovary is superior with a single style and stigma.
The style arises from a depression in the top of the ovary.
There are many ovules in each locule.
The fruit is a dry capsule that splits into the cavities of the 5 chambers.
Pieris formosa and Pieris japonica are the better known species.
These two and sometimes Pieris floribunda are used in the production of cultivars.
Other species are P. cubensis, P. nana, P. phillyreifolia and P. swinhoei.
Pieris formosa and P. japonica both have fruit capsules that are smooth (no hairs)
and the style is only slightly sunken into the top of the ovary.
Pieris japonica leaves have teeth that may be confined to the tip or extend down
towards but not to the base. Secondary veins are not depressed.
Pieris formosa leaves have teeth from the tip to the base and the secondary
veins are easily seen and depressed.
Pieris japonica.
It is known as the Japanese Andromeda or Japanese pieris.
A shrub up to 3m high and almost as wide.
It is evergreen and densely covered in foliage.
New leaves are a bronze colour.
Adult leaves are dark green above and paler underneath.
Leaves are alternately arranged and on short stems.
The blades are ovate to oblong to lance-shaped and up to 8 cm long.
Secondary veins may be indistinct and are not depressed.
The teeth on the edges do not extend to the base of the leaf.
Inflorescences are sprays 10 to 15 cm long.
They are covered in drooping white or pink flowers.
Cultivars are various shades of white, pink and red.
Pieris formosa.
It is a shrub or small tree up to 5 m high.
Branches can be smooth or hairy.
New leaves are reddish.
Leaves are on stalks up to 1.5 cm long.
The blade is oblong or lance-shaped and up to 14 cm long.
The whole margin is toothed.
The small veins are easily seen on both surfaces.
Inflorescences are up to 10 or 20 cm long with the flowers mainly on one side.
Flowers are on stalks only a few mms long with bracteoles.
The 5 sepals are about 4 mm long, pale green with pink tones.
The 5 white or pinkish petals are fused into an urn-shaped tube.
The end of the tube is constricted and has the 5 small lobes on it.
The tube in up to 8 mm long.
The stamen filaments are only 4 mm long and have hairs on them.
The single style is slightly sunken into the top of the ovary.
The fruit is a 4 mm capsule.
J.F.
