Tall, White Brassicas

Large Bitter-cress Common Sea Kale Garlic Mustard Common Dame's-violet

What are they?

This page covers members of the brassica family that typically grow more than 50cm in height and have white - usually showy - flowers. Since the group includes a number of species that are not particularly closely related, they differ quite widely in their appearance, which should actually help with the identification process. They all share the family traits of four-petalled, white flowers that are followed by distinctive seed pods.

Where are they found?

This is a group of only loosely related plants, so there is much variation in the habitat choices. However, the habitat can be a valuable aid to identification for some species - especially the coastal ones, so be sure to check these details in the individual species notes below.

Identification

All these plants have white, four-petalled flowers, so you need to look elsewhere for identification clues. Check the seed pods, if they are present, as well as leaf size and shape. As noted above, the habitat and location is also often useful to note.



Garlic Mustard      Alliaria petiolata

Very common and widespread biennial of hedgerows, woodland edge and similar places. Flowers April to July. Often grows in large, extensive stands, setting large quantities of seed. Young plants germinate in late summer or autumn and produce a few basal leaves, then gain height and flower the following spring. The whole plant has a garlic smell and taste. Leaves broadly triangular with coarsely toothed edges, the overwintering leaves being rather dull, but fresh spring leaves are bright, shining green; seed pods long and linear.

Garlic Mustard Garlic Mustard Garlic Mustard Garlic Mustard
Habit
Flowers
Early leaves
Seed pods


Annual Honesty      Lunaria annua

Introduced. A popular garden plant and often escaping into rough, grassy areas and roadsides. Flowers April to May. Flowers may be rich, pinkish-purple or white, with the two colours often (though not always) growing together. Leaves broadly triangular with a rounded base and strongly toothed edges. Seed pods are flat, rounded discs which, when completely dried and after the seeds have gone, are popular for flower-arranging or Christmas decoration.

Annual Honesty Annual Honesty Annual Honesty Annual Honesty
Habit
Habit
Basal leaf
Seed pods


Common Dame's-violet      Hesperis matronalis

Introduced as a garden plant and occasionally escaping into rough, grassy areas and roadsides, though much less common than the similar Annual Honesty. Flowers May to July. Flowers heavily scented, mauve or white, with the two colours rarely growing together. Leaves spear-shaped with lightly toothed edges. Seed capsules long, thin and held erect.

Common Dame's-violet Common Dame's-violet Common Dame's-violet Common Dame's-violet
Habit
Flowers
Leaf
Seed capsules


Horse-radish      Armoracia rusticana

Originally introduced as a culinary plant and now widespread in all kinds of waste places and grassy verges. Flowers May to August. The tough, dock-like, basal leaves are distinctive once known and can form quite extensive patches as the plant spreads by creeping root systems. Flowering shoots are taller than the basal leaves and have narrow, strap-like leaves on their stems.

Horse-radish Horse-radish Horse-radish Horse-radish
Flowers
Flower
Basal leaves
Stem leaves


Large Bitter-cress      Cardamine amara

A native of damp soils, usually avoiding chalky areas. Widespread, though local, along streams and ditches and especially around damp places in woodland and scrub. Flowers April to June. A showy species that often grows in quite large colonies along muddy waterside edges. Leaves are compound, the basal leaves with rounded lobes and those of the stems more angular and narrower. Seed pods long, linear and upright. When in full flower, the violet (not yellow) anthers are very distinctive.

Large Bitter-cress Large Bitter-cress Large Bitter-cress Large Bitter-cress
Habit
Flowers
Flower with violet anthers
Basal leaf


Tower Mustard      Turrita glabra

A Nationally Scarce species, in our area more or less confined to Breckland, where it occurs on a few sandy, grass heaths. One or two plants are known from a small handful of other localities elsewhere. Flowers May to July. A distinctive plant, forming a leaf rosette in the first year, then pushing up a tall, slender flower spike in the second year. Flowers are small but relatively showy due to the tall, slender appearance of the plant. The entire plant is blue-green, waxy and hairless. Seed pods are long and slender and carried close to the main stem.

Tower Mustard Tower Mustard Tower Mustard Tower Mustard
Habit
Flowers
Flowers
Waxy leaves clasp the stem


Wild Radish      Raphanus raphanistrum subsp. raphanistrum

Probably an ancient introduction from Neolithic times and now a widespread and common plant throughout most of our region on a wide range of disturbed ground, field margins, waste places, tips and similar locations. Flowers May to September. Once known, this is an easy plant to recognise, with its coarse, bristly leaves and stems and its seed pods that have faint ribbing between the developing seeds. Plants are often relatively short, but usually have spreading branches, making them more noticeable and obvious than the species covered under the small, white brassicas. Flowers usually have dark veins and populations usually have a mix of both white and pale yellow flowered plants among them. The petals have long bases to them, forming a distinct cross shape to the flower.

Wild Radish Wild Radish Wild Radish Wild Radish
Flower
Flower
Basal leaves
Seed pod


Common Radish      Raphanus sativus

Introduced. Occasionally grown as an arable cover crop in a mixture with other brassicas and sometimes found as a relic of cultivation along field edges. Flowers throughout much of the year, depending on sowing time. Flowers white or whitish with reddish veins, but the pink, red or purple colour can extend variably across much of the petal. Basal leaves rough with coarse, uneven lobes. Seed pod more or less rounded with a smooth outline, showing little or no constriction between the seeds.

Common Radish Common Radish Common Radish Common Radish
Flowers
Flower
Basal leaf
Seed pod


Common Sea Kale      Crambe maritima

Native. Abundant on shingle beaches along much of the Suffolk coast but almost absent from Norfolk except for a small area of The Wash. Flowers May to June. Easily recognised by it thick, waxy, cabbage-like leaves.

Common Sea Kale Common Sea Kale Common Sea Kale Common Sea Kale
Habit
Flowers
Basal leaf
Seed pods


Greater Sea Kale      Crambe cordifolia

Introduced from the Caucasus and grown as a garden ornamental in municipal parks, where there is space for its large size. Rarely found as an escape from cultivation along the Norfolk coast. Flowers May to June. Forms clumps of large, crinkly leaves with a massive, spreading head of tiny, white flowers. Very imposing when the huge flower panicle grows up to two metres high.

Greater Sea Kale Greater Sea Kale Greater Sea Kale Greater Sea Kale
Habit
Habit
Flower
Basal leaf


Hoary Alison      Berteroa incana

Introduced from Europe. Rare in our region but long established in one or two locations in the Breckland area. Flowers June to August. A slender plant, growing to 60cm but often shorter. The whole plant is covered in dense, star-shaped hairs.

Hoary Alison Hoary Alison Hoary Alison Hoary Alison
Habit
Flowers
Leaf
Seed pods