Weigela (not Weigelia) is in the Bush honeysuckle family Diervillaceae.
It is also seen in a loosely defined Caprifoliaceae family.
Classification of Weigela, and its species has changed a number of times and some Weigela species were in Diervilla.
Plants of the World Online (Kew) accepts 10 species that are native to eastern Asia with most from Japan.
They are deciduous shrubs 1 to 2 m high or small trees to 5 m.
Young twigs are 4-angled in cross section and may have hairs.
Opposite leaves are up to 10 or 15 cm long.
There may be a petiole up to around 1 cm long or almost none.
Blades are ovate to oblong with a pointed tip and a toothed edge (serrate).
There may be a few to dense hairs on the lower surface and some or none on the upper.
Inflorescences of 1 to a few flowers are terminal on the previous years short side branches.
Flowers are on a pedicel or directly attached and bracts and bracteoles may be present.
The 5 sepals in the calyx may be almost free or joined for half or two-thirds of their length.
Lobes may all be the same length or 2 may be slightly shorter.
The corolla has a bell or funnel-shaped tube with a narrow base that widens gradually or abruptly.
The 5 lobes may be of the same length (radially symmetric) or be slightly 2-lipped (bilaterally symmetric).
The corolla, up to 4 cm long can be white, pink, red, purple or rarely yellow.
Colours may change as the flowers age.
There may be simple hairs on both surfaces.
The 5 stamens, alternating with the petals are inserted onto the corolla tube.
There may be hairs on the base of the filaments and the ridges that run down the tube below the insertion.
Yellow or reddish anthers can be free or fused and usually lie in the tube or just past the mouth.
The narrow inferior ovary consists of 2 fused carpels.
The thin style extends to, or past the mouth of the corolla tube.
The stigma may be spherical (capitate) or 2 lobed.
Fruit are capsules that may be slightly curved or the top may taper to a point.
They split into 2 sections starting from the tip.
Each half has numerous small angled or slightly winged seeds.
J.F.
