Sea Lettuce / Spring / Summer / Autumn / Winter / Edible

Common Names

Sea lettuce, Sea Salad

Botanical Name

Ulva lactuca

Scientific Classification

Kingdom – Plantae

Order –Ulvales

Family – Ulvaceae

Habitat

Found growing on rocks and in sandy rockpools. It prefers sheltered areas.

A very commonly found plant in the UK and Ireland, with recordings of it across western Europe.

Physical Characteristics:

Fronds

This seaweed literally looks like lettuce leaves in the sea. The fronds are green, translucent and quite touch, and they grow in little florets.

They tend to be about palm sized, but can grow to 30cm across.

Holdfast

The holdfast is small, discoid, and flattened

Known Hazards

Sea lettuce likes living in polluted areas, so can accumulate heavy metals and other chemicals.

As with most seaweeds, the high iodine content means that those with thyroid issues should be careful not to consume too much if they are already taking iodine supplements. Likewise, the salt content may be a problem for those who need to limit their salt intake. In general, there are more hazards associated with the environment you find it in than from the algae itself. It is wise to check water quality data from the Environment Agency (https://environment.data.gov.uk/bwq/profiles/ ) to see whether there are issues with chemical or sewage pollution in the water, and to rinse your harvested seaweed well with clean water to be on the safe side. You should also be aware of slippery or unstable rocks, and the possibility of the sea coming round quickly and cutting you off from land. Check the tide times, only harvest from areas you can get to safely, and take someone with you to get help if you get into difficulty.

Could Be Confused With

It is a close relative of Gutweed/mermaid’s hair, which has small green threads instead of wide fronds. Sometimes a sun-bleached piece of laver may appear greenish, but it will not have the curly edges associated with sea lettuce.

Edible Uses

As the name suggests, this is a great addition to salads. It is very common and grows throughout the year, so is a great one to include in your diet on a regular – but moderate – basis.

It is wonderful made into crisps due to its thin texture, and can be used as a vegetable in many dishes.

You could dry and powder it and experiment with using it as a thickener for soups, stews or even creative ice creams.

Notes on Herbal uses

As with all seaweeds, sea spaghetti is very high in minerals and salts due to needing to retain enough water in a very saline environment. This makes it a wonderful tonic food, important in the maintenance of a thriving nervous, immune and just about every other body system.

Consume in moderation – see the safety section above. Clinically (by medical herbalists), seaweeds are often used for skin and skeletal issues.

Conservation Considerations

This is a very common seaweed, which is capable of surviving where other species cannot, such as in highly polluted areas. If there is a higher than usual amount of sea lettuce it may be an indication that the area is polluted. Be aware of this when harvesting.

Extra notes from the Foragers

Often to be found washed up in the rock pools, sometimes you will be lucky enough to come upon a garden of sea lettuce growing altogether.

Late spring to late Autumn tends to be the time during which it is most abundant, but it can be found all year around.

Take fronds that look fresh and vibrant green – you will often see white or yellow material with the same texture as sea lettuce which is simply sun-bleached.

Amazingly Sea Lettuce can keep living even when detached from the rocks so this is one that, with caution, we can pick detached from the rocks.

If the area is sheltered, sea lettuce can occasionally continue to grow in floating rafts if it has become detached from its substrate.