Viola Tricolor.
Heartsease or Heart’s Ease is used as an annual or perennial ground cover.
World Flora Online recognises 3 subspecies and one form but others recognise up to 6.
It is one parent of most of the flowers commonly know as ‘pansies’.
They are erect plants from 10 to 30 cm high with a spread of up to 40 cm.
The branching stems are hollow and may be smooth or have soft hairs.
There is no basal rosette with the leaves alternating on branching aerial stems.
There are large, deeply lobed, leafy stipules at the base of the petioles.
Leaves near the base of the stems are ovate to heart-shaped.
Those higher up are more oblong to lance-shaped with a pointed tip.
The edge of the lower leaves have shallow rounded lobes (crenate) while the upper
ones have more sharply toothed edges.
Inflorescences are solitary flowers in the leaf axils of the main and side branches.
They are on long pedicels that have a pairs of bracteoles near the top.
The bisexual, bilaterally symmetric flowers are around 1.5 cm across.
The upper and lateral pairs of petals point up and the lower one points down.
In horticultural terms this makes them a ‘pansy’ rather than a ‘violet’.
There are 5 long, narrow green sepals with pointed tips.
They have a moderately large basal appendage.
There are 5 separate, slightly overlapping petals.
The upper or posterior pair, and the slightly smaller lateral ones are round to obovate with a narrower base.
The lateral pair has hairs in the throat.
The lower or anterior petal is broadly obovate with a shallow notch.
The base of this petal extends into a spur.
All petals have a white base which is more obvious on the lower 3 petals.
The lower 3 petals also have dark nectar guides.
The typical colours are purple upper petals, white laterals and a yellow lower petal.
There are 5 stamens whose short filaments are fused into a tube around the ovary.
The bases or the lower 2 have nectar containing spurs that lie in the spur of the lower petal.
The superior ovary, of 3 fused carpels, has one locule.
The numerous ovules are attached to parietal placentas.
The short, thin style has a broader stigma.
The fruit are loculicidal capsules that open explosively into 3 valves.
There are many cultivars with V. tricolor as one of the parents.
Colours of these include the basic purple, yellow and white plus blue, violet and gold.
There may be purple blotches on the lower three petals as well as the dark purple lines.
There are also some with only 2 colours.
J.F.
