Nasturtium officinale (Watercress)

Botanical name

Nasturtium officinale

Other names

Watercress, Water cress, Rorippa nasturtium-aquaticum, Craches, Flixweed, Fluxweed, Water grass, Water radish, Well cress, Rorippa nasturtium, Brooklime, Bank cress

Genus

Nasturtium Nasturtium

Species

N. officinale - N. officinale is a mat-forming, edible, aquatic, semi-evergreen perennial with hollow stems bearing pinnate leaves divided into ovate, mid-green leaflets and clusters of tiny, white flowers from late spring into autumn.

Foliage

Deciduous

Habit

Mat Forming

Toxicity

All parts are edible but care should be taken if harvested in the wild. Plants growing in water that drains from fields where livestock is kept should not be used raw.

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Colour

Flower

White in Spring; White in Summer; White in Autumn

Foliage

Mid-green in All seasons

General care

Pruning

Trim lightly in autumn.

Propagation

Easily roots from nearly every part of the plant.

Propagation methods

Leaf cuttings, Seed, Stem segments, Stem tip cuttings

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Monthly care advice

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Where to grow

Nasturtium officinale (Watercress) will reach a height of 0.5m and a spread of 1m after 2-5 years.

Suggested uses

Aquatic, Containers, Ground Cover, Underplanting, Waterside

Cultivation

Best grown in containers in slow-moving water 5cm deep. Can be grown in moist soil in partial shade with winter protection.

Soil drainage

Boggy damp conditions, Moisture-retentive, Pond/In water

Light

Partial Shade, Full Sun

Aspect

South, West

Exposure

Sheltered

UK hardiness Note: We are working to update our ratings. Thanks for your patience.

Hardy (H4)

USDA zones

Zone 11, Zone 10, Zone 9, Zone 8, Zone 7, Zone 6, Zone 5, Zone 4, Zone 3

Defra's Risk register #1

Plant name

Nasturtium officinale (Watercress)

Common pest name

Cassava whitefly; Cotton whitefly; Sweet potato whitefly; Tobacco whitefly

Scientific pest name

Bemisia tabaci non-European populations

Type

Insect

Current status in UK

Absent

Likelihood to spread to UK (1 is very low - 5 is very high)

2

Impact (1 is very low - 5 is very high)

5

General biosecurity comments

Non-European populations of Bemisia tabaci pose an additional risk to European populations due to the potential for introducing non-European viruses.

Defra's Risk register #2

Plant name

Nasturtium officinale (Watercress)

Common pest name

Cassava whitefly; Cotton whitefly; Sweet potato whitefly; Tobacco whitefly

Scientific pest name

Bemisia tabaci European populations

Type

Insect

Current status in UK

Absent

Likelihood to spread to UK (1 is very low - 5 is very high)

2

Impact (1 is very low - 5 is very high)

4

General biosecurity comments

The UK has a protected zone in place for this pest which helps to mitigate the risk of entry and establishment. An EFSA opinion is currently being discussed at the EU Annexes Working Group which recommends further strengthening of the regulation.

Defra's Risk register #3

Plant name

Nasturtium officinale (Watercress)

Common pest name

Lance nematode; Nematode; Lance

Scientific pest name

Hoplolaimus spp.

Type

Nematode

Current status in UK

Absent

Likelihood to spread to UK (1 is very low - 5 is very high)

2

Impact (1 is very low - 5 is very high)

4

General biosecurity comments

Nematode species potentially affecting a wide variety of crops; prohibition of soil likely to mitigate risk substantially; keep under review in light of interceptions or findings should they occur in the EU.

About this section

Our plants are under greater threat than ever before. There is increasing movement of plants and other material traded from an increasing variety of sources. This increases the chances of exotic pests arriving with imported goods and travellers, as well as by natural means. Shoot is working with Defra to help members to do their part in preventing the introduction and spread of invasive risks.

Traveling or importing plants? Please read "Don't risk it" advice here

Suspected outbreak? Click here for contact details to report to the relevant authority.

Date updated: 7^th March 2019 For more information visit: https://planthealthportal.defra.gov.uk/