Onagraceae: Evening-primrose Family — Clarkia

All members of the Evening-Primrose family have 4-petaled flowers, and many of them are showy.  Despite the name, they do not necessarily bloom in the evening.  There is a separate family called Primrose (Primulaceae).

Clarkia is a particularly attractive genus with a wide variety of flowers. Some are immediately recognizable, but others require careful attention to such details as whether the buds are upright or nodding, the size and shape of the fruits, whether the stamens are all of the same length, and whether the axis of the inflorescence is straight or recurved.  The Four-spot or Winecup Clarkia (Clarkia purpurea subsp. quadrivulnera) deserves a special mention for the variability of its flowers.

Chaparral Clarkia – Clarkia affinis

Blooms:

May–June

Plant Height:

< 80 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Woodland openings, chaparral

Notes:

Like Four-spot Clarkia (Clarkia purpurea subsp. quadrivulnera, see below), this has erect buds, and smallish pink to lavender flowers (occasionally deep maroon).  There are 8 stamens, similar in length and color.  Petals are often red-flecked.  It is most easily distinguished by its fruits, which are longer and proportionately narrower (> 9 × as long as wide) than those of Four-spot Clarkia (which are < 8 × as long as wide).  This is more common inland and in the south or southeastern parts of the county.

Willow-herb Clarkia – Clarkia epilobioides

Blooms:

Apr–May

Plant Height:

< 70 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Shaded places

Notes:

A small plant with smallish, obovate petals which begin white and fade to pink with age, not flecked with purple. Buds are nodding. Leaves are linear to narrowly lanceolate or oblanceolate. Sepals remain fused in 4s or 2s, often reddish in color.

Jolon Clarkia – Clarkia jolonensis

Blooms:

Apr–June

Plant Height:

< 60 cm

Flower Size:

Small-medium

Origin:

Native

Rare or endangered:

Yes – 1.b2

Habitat:

Dry chalk-rock shale slopes near Jolon

Notes:

Found only near Jolon, this could easily be mistaken for Lewis’ Clarkia (Clarkia lewisii, see below).  But it can be distinguished by the absence of any red line at the base of the petals and, more importantly, by the axis of its inflorescence, which is erect rather than recurved.  Buds are reflexed, though becoming erect as the flower opens.  The anthers are variable, the outer being longer and lavender, the inner shorter and paler.

Lewis’ Clarkia – Clarkia lewisii

Blooms:

Apr–May

Plant Height:

< 70 cm

Flower Size:

Medium–large

Origin:

Native

Rare or endangered:

Yes – 4.3

Habitat:

Coastal scrub, woodland, chaparral

Notes:

Found only in Monterey and San Benito Counties, this clarkia is common on the Peninsula. Petals are 1–3 cm, pink to lavender, generally with pink speckles and often with a dark pink or red line across the base of the petals. Buds are nodding. The outer anthers are lavender and noticeably longer than the inner, paler anthers. The entire base of the petals is occasionally deep crimson, similar to Ruby Chalice Clarkia (Clarkia rubicunda, see below), but the plant can be distinguished by its nodding buds and the two different forms of its anthers.

Waltham Creek Clarkia – Clarkia modesta

Blooms:

Apr–May

Plant Height:

< 70 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Shaded places

Notes:

This is very similar to Ramona Clarkia (Clarkia similis, see below).  Both have nodding buds and diamond-shaped to oblanceolate petals.  The anthers are variable, the outer being longer and purple, the inner shorter and paler.  Fruits are long, slender and 8-grooved.  The main (rather slight) differences between the two species is in the size of the petals (this has petals that are 8–12 mm) and their coloration: this has pink petals which are not lighter towards their base.

Four-spot / Winecup Clarkia – Clarkia purpurea subsp. quadrivulnera

Blooms:

Apr–Aug

Plant Height:

< 100 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Open grassy or shrubby places

Notes:

This is an extremely common clarkia, with flowers that are quite variable in their appearance.  While some are almost white, most are pink.  They range from very pale to very dark; all generally have a darker blotch on the margin of each of the petals.  Many are pure deep maroon (these are the ones commonly called Wine-cup Clarkia).  Like Chaparral Clarkia (Clarkia affinis, see above), this has erect buds and flowers, with 8 stamens similar in length and color.  The stamens are sometimes useful in distinguishing flowers that may look like a small Lewis’ Clarkia (Clarkia lewisii, see above).  This and Chaparral Clarkia are most easily distinguished by their fruits; this has fruits which are shorter and proportionately fatter (< 8 × as long as wide) than those of Chaparral Clarkia (which are > 9 × as long as wide).

Diamond Clarkia – Clarkia rhomboidea

Blooms:

Mar–Sept

Plant Height:

< 100 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Yellow pine forests & other woodland

Notes:

Like Elegant Clarkia (Clarkia unguiculata, see below), this has erect stems with flowers borne at various points along the stem.  Buds are nodding.  Petals are pink to lavender, narrowly ovate to diamond-shaped, distinguished by the broad claw at the base of the petals and the presence of distinct lobes on the claw.  Fruits are 4-grooved.

Ruby Chalice Clarkia – Clarkia rubicunda

Blooms:

May-Aug

Plant Height:

< 150 cm

Flower Size:

Medium–large

Origin:

Native

Habitat:

Woodland openings, chaparral near coast

Notes:

This is sometimes called Farewell to Spring, although this can cause confusion with the often cultivated Clarkia amoena.  It has rose-pink to lavender petals, obovate to fan-shaped, generally with a prominent reddish zone at the base.  It can be mistaken for Lewis’ Clarkia (Clarkia lewisii, see above), which is occasionally found with deep red petal bases, but there are several features that allow the  two to be distinguished.  First, the Ruby Chalice Clarkia has erect, not nodding buds.  Second, its eight anthers are all alike (Lewis’ Clarkia has two sets of 4 anthers quite distinct from one another).  Third (and much less easily visible), the hypanthium in Lewis’ Clarkia has a ring of hairs at its base, the Ruby Chalice Clarkia lacks this feature.

Ramona Clarkia – Clarkia similis

Blooms:

Apr–June

Plant Height:

< 90 cm

Flower Size:

Small-medium

Origin:

Native

Habitat:

Dry slopes, mainly interior

Notes:

This is very similar to Waltham Creek Clarkia (Clarkia modesta, see above).  Both have nodding buds and diamond-shaped to oblanceolate petals.  The anthers are variable, the outer being longer and purple, the inner shorter and paler.  Fruits are long, slender and 8-grooved.  The differences between them are in 1) the size of the petals (this has petals that are 6–10 mm), and 2) their coloration (this has pink petals which are shaded lighter towards their base, and are generally dark-spotted or -flecked).

Redspot Clarkia – Clarkia speciosa subsp. speciosa

Blooms:

May–July

Plant Height:

< 60 cm

Flower Size:

Large

Origin:

Native

Habitat:

Dry places, woodland

Notes:

This is a striking clarkia, immediately recognizable with its dark purple-red or lavender flowers, generally with red spots. The plant is decumbent to erect. The stigma is prominently exserted beyond the anthers. Buds are erect. The fruits are conspicuously 8-grooved or -ribbed.  The stem is covered with short, soft hairs. Branches on well-developed plants can be many but few-flowered.

Elegant / Canyon Clarkia – Clarkia unguiculata

Blooms:

Apr–Sept

Plant Height:

< 100 cm

Flower Size:

Large

Origin:

Native

Habitat:

Dry slopes

Notes:

A very common clarkia, immediately recognizable by its spreading petals that are more or less triangular or diamond-shaped, abruptly narrowing to a slender claw.  The flowers grow along the length of tall stems, sometimes in profusion, creating spectacular displays. The typical color is dark pink with deep crimson sepals, but it can also be found in salmon pink, red and even white forms. The outer anthers are larger an darker in color than the inner.