From Oyster seed to Harvest

The Production Cycle

  • It takes approximately three years to produce a fully grown oyster. The first step is to grow the seed from 0.2 grams (approx 6mm) to 10-15 grams
  • In 18 months from seed, the oysters will have reached about 30 to 40 grams and are referred to as half grown oysters.
  • The fastest growing oysters will reach marketable size (80 - 100 grams) after 2.5 years

The Provison of Seed

The production strategy of Foylemore Oysters involves the use of innovative techniques and best aquaculture practices.

In 2012 larvae remote setting techniques were implemented to product oyster triploid and diploid seed. The main goal was to produce good quality seed naturally grown in the Foyle with a view to lowering the final production costs of quality oysters.

The trials were successful and the results encouraging. However, the technique was too time consuming and, with the build up of the annual production over 100 tonnes it became difficult to deal with merging deadlines. Nevertheless, the technique remains a goiod option for the future.

The use of hatchery oyster seed also became a more cost effective technique.

The Culture Technique

Oysters are farmed in plastic mesh bags placed on iron trestles located on the intertidal zone of the shore.

Oyster bag mesh size and oyster density will be adapted according to the development of the oysters.

1,000 seed oysters are placed in 4mm bags. Oyster seeds are fragile as they have a very thin shell and have not yet been exposed to outdoor conditions. Special care is required to prevent mortality.

The Origin of Seed

Foylemore Oysters work exclusively with sterile seed from French hatcheries. Seed from various regions were tested on the site and the best results were found with France Naissain and France Turbot hatcheries.

Grade 6mm seed are purchased from the hatcheries in the autumn and spring.



Head Office: 18 Culmore Point, L'Derry, Northern Ireland, BT48 8JW

Telephone: +44 (0) 7795 600 327