Biodiversity Plants

The Cress Family

(Cruciferae)

Family Description

The plants in the Cress Family are known as Crucifers. They are all types of herb. They have four petals arranged in a cross. They include plants such as Radish, Turnip and Mustard.

Most Crucifers, including Shepherds Purse and Bittercress, are thought of as weeds. They are often unpopular, because they compete with garden plants and crops. However, they are an important and fascinating group of plants.

Insects, such as bees, flies, moths and butterflies pollinate many Crucifers. Therefore, the flowers often have large, brightly coloured petals and usually secrete nectar as an extra attraction for the insects.

People have used Crucifers for hundreds of years. Many are used for food, including Watercress, Radish and Turnip. Many have been bred into varieties that would not normally grow in the wild, such as Cabbage, Brussels Sprouts and Broccoli. They are sometimes grown for their oil (e.g. Rape Seed Oil) or for animal feed.

Woad is a famous Crucifer. It was used by thousands of people, in the middle-ages, who boiled it to produce a blue dye, used to colour fabrics and clothes.

From the Cress Family, you can explore:

Jack-by-the-hedge

Cuckoo Flower

Water Cress

Jack-by-the-hedge

Alliaria petiolata

Jack-by-the-Hedge is easily spotted because it grows in large groups, producing a bed of bright white flowers.

The leaves vary in shape - many are kidney-shaped or heart-shaped.

Habitat
Hedgerows, woodland margins, shady gardens, scrub, roadsides and waste ground.

Damp, partially shaded areas on high nutrient soils.

It manages to grow in most places, but prefers limestone soils.

Special features
The leaves, fruit and root smell of garlic, giving it its other names of "Garlic Mustard" and "Hedge Garlic".

Reproduction
Jack-by-the hedge often reproduces by vegetative reproduction, by growing buds straight out of its roots.

Also produces seeds.

Visited by various small insects but can pollinate itself.

Distribution
Seasonal

The flowers can be seen throughout April, May and June.

Geographical

Found throughout Britain, but scarce in Scotland. Common throughout lowland Britain though less frequent in the north and west.

Fun Fact
This plant used to be known as "Jack-run-along-by-the-hedge" because it is often found growing in hedgerows.

Cuckoo Flower

Cardamine pratensis

The Cuckoo Flower is a member of the Cress Family. Each flower has four soft petals, which are a pale lilac-pink colour becoming whiter towards the centre of the flower. Each petal has a notch in the middle.

Cuckoo Flowers often form large colonies made up of hundreds of plants.

	Habitat	Damp areas, such as marshes, stream and pond edges. Meadows and pastures, open woodland, hedgerows and roadsides. It can grow in the shade.
	Special features	White Cuckoo flowers are occasionally found.
	Reproduction	The Cuckoo Flower is pollinated by bee-flies and long-tongued hoverflies, producing seeds. If the air and soil are very moist, the Cuckoo Flower can also reproduce by vegetative reproduction, sprouting shoots straight out of the adult plant. These shoots grow roots and grow into new plants.
	Distribution	Seasonal It was called the Cuckoo Flower because it flowers in April and May, when the cuckoo starts to sing. Geographical Throughout Britain.
	Folklore	People in Germany used to believe that if the Cuckoo Flower was picked and brought inside, the house would be struck by lightening.
	Fun Fact	A famous English physician - Mr. Nicholas Culpeper, wrote in his book of 1826 - that the Cuckoo Flower restored a lost appetite and helped digestion.

	Water Cress *Nasturtium officinale*	Water Cress is popular in salads and it is deliberately grown in shallow rivers. It has been boiled or eaten raw for centuries. In Britain, it was first cultivated in Kent around 1808. It also grows wild in streams and ditches throughout Britain and can be recognised by its dark green tongue-shaped leaves and delicate white four-petal flowers.
	Habitat	Wet soil and shallow water. Common in the lowlands, at the edges of streams, ditches and springs. It grows well in flowing water. It needs a lot of sunlight.
	Special features	The stems are hollow, which aids gas exchange. This is common in many plants which grow in water. The leaves grow opposite each other on a stalk, ending with one odd, larger leaflet.
	Reproduction	Various flies and small bees pollinate its little white flowers. It can also pollinate itself. The resulting seeds grow inside a long seed pod, in two clear rows.
	Distribution	Geographical Throughout the British Isles.
	Folklore	Water Cress was often mentioned in old early Irish nature poems: "Water Cress, little green-topped one On the brink of the blackbird's well."
	Fun Fact	Water Cress is very high in Vitamin C and used to be eaten to prevent scurvy.