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- Primula japonica
Primula japonica — Japanese primrose
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Facts
Japanese primrose is native to Japan and is widely cultivated for its showy purple flowers that arise from rosettes of leaves up to 25 cm (10 inches) long in the spring. In New England, it occasionally escapes gardens into forest fragments, the edges of brooks, and waste areas in Massachusetts and Vermont.
Habitat
Anthropogenic (man-made or disturbed habitats), forest edges, shores of rivers or lakes
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Massachusetts
- Vermont
- Flower petal color
-
- blue to purple
- pink to red
- white
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Leaf blade edges
- the edge of the leaf blade has teeth
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Stamen number
- 5
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit length
- 7–8 mm
-
Clonal plantlets
- Bulbils
- the plant does not appear to have bulbils
- Bulblets replace flowers
- there are no bulblets where the flowers are located
-
Flowers
- Anther spurs
- the anthers do not have spurs on them
- Calyx growth after flowering
- the calyx grows to cover or partially cover the fruit
- Calyx symmetry
- there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
- Carpels fused
- the carpels are fused to one another
- Cleistogamous flowers
- there are no cleistogamous flowers on the plan
- Corolla palate
- no
- Corona lobe length
- 0 mm
- Epicalyx
- the flower does not have an epicalyx
- Epicalyx number of parts
- 0
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower diameter
- 9–15 mm
- Flower petal color
-
- blue to purple
- pink to red
- white
- Flower reproductive parts
- the flower has both pollen- and seed-producing parts
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Flowers sunken into stem
- no
- Form of style
- the style is knob-like at the tip, and unbranched
- Fused stamen clusters
- NA
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Inflorescence one-sided
- the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
- Inner tepals (Rumex)
- NA
- Nectar spur
- the flower has no nectar spurs
- Number of carpels
- 5
- Number of pistils
- 1
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Number of styles
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal and sepal colors
-
- blue to purple
- pink to red
- white
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal folds or pleats
- the petals of the flower do not have folds or plaits
- Petal hairs (Viola)
- NA
- Petal number
- 4–5
- Petal tips (Cuscuta)
- NA
- Reproductive system
- all the flowers have both carpels and stamens (synoecious)
- Scales inside corolla
- no
- Sepal and petal color
- the sepals are different from the petals
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal number
- 4–5
- Sepals fused only to sepals
- the sepals are fused to each other (not other flower parts), at least near their bases
- Stamen attachment
- the stamens are attached at or near the bases of the petals or tepals
- Stamen number
- 5
- Stamen position relative to petals
- the stamens are lined up with the petals
- Style petal-like
- the styles are not petal-like
- Umbel flower reproductive parts
- NA
- Upper lip of bilabiate corolla
- NA
-
Fruits or seeds
- Achene relative orientation
- NA
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 7–8 mm
- Fruit locules
- one
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
- the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
- Legumes (Fabaceae)
- NA
- Mericarp length
- 0 mm
- Mericarp segment shape (Desmodium)
- NA
- Other markings on berry
- NA
- Ovary stipe
- the ovary or fruit does not have a stipe
- Placenta arrangement
- the plant has free-central placentation, where the ovules develop on a central column in a compound ovary lacking septa or with septa at the base only
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Septum in fruit (Brassicaceae)
- NA
- Wings on fruit
- the fruit does not have wings on it
- prickles on fruits
- the fruits do not have thorn-like defensive structures
-
Glands or sap
- Glands on leaf blade
- the leaf blades do not have glandular dots or scales
- Sap
- the sap is clear and watery
- Sap color
- the sap is clear
-
Growth form
- Growth form
- the plant is an herb (it has self-supporting stems)
- Horizontal rooting stem
- the plant does not have stolons
- Lifespan
- the plant lives more than two years
- Parasitism
- the plant is not parasitic
- Plant color
- the leaves or young stems of the plant are green
- Plants darken when dry
- no
- Spines on plant
- the plant has no spines
- Underground organs
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
-
Leaves
- Bracteole number (Apiaceae)
- 0
- Bracts in plantain (Plantago)
- NA
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment length to width ratio (compound lvs only)
- 0
- Hairs on underside of leaf
- the underside of the leaf is not hairy, or it has very few hairs
- Hairs on upper side of leaf
- the upper side of the leaf is not hairy, or it has very few hairs
- Inflated hairs on leaf
- the leaf blade has inflated hairs on it
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Leaf blade base
- the leaf has a distinct leaf stalk (petiole)
- Leaf blade base shape
- the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
- Leaf blade edges
- the edge of the leaf blade has teeth
- Leaf blade length
- 150–400 mm
- Leaf blade shape
-
- the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
- the leaf blade is oblong (rectangular but with rounded ends)
- the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- the leaf blade is spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade width
- 50–130 mm
- Leaf duration
- the leaves drop off in winter (or they whither but persist on the plant)
- Leaf form
- the leaves are green, with an expanded blade and a leaf-like texture
- Leaf spines
- there are no spines on the leaf edges
- Leaf stalk
- the leaves have leaf stalks
- Leaf teeth and lobes
- the leaf blade margin has outward-pointing teeth
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaf variation
- NA
- Leaves per node
- the leaves are growing only at the base of the plant (i.e., basal)
- Pinnately compound leaf type
- NA
- Specific leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Stipule features
- NA
- Stipules
- there are no stipules on the plant
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Massachusetts
- Vermont
- Specific habitat
-
- edges of forests
- man-made or disturbed habitats
- shores of rivers or lakes
-
Stem, shoot, branch
- Branched tendrils
- NA
- Flowering stem cross-section
- the flowering stem is circular, or with lots of small angles so that it is roughly circular
- Hairs between stem nodes
- the stem has no hairs between the nodes
- Leaves on stem
- the flowering stem has no leaves above the base
- Plant height
- 30–80 cm
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
1. Primula japonica Gray E
Japanese primrose. MA, VT. Gardens, forest fragments, brook sides, waste areas. The reports of Primula anisodora Balf. f. & G. Forrest (e.g., Weatherbee 1996, Sorrie and Somers 1999) are based on a collection of P. japonica, as evidenced by the relatively more slender and adaxially farinose sepals and larger corollas— Sorrie 2374 ( NEBC!).