Seed Supply

Leading Seed Supplier

Our starting material allows seaweed farmers to scale up and specialise. With reliable deliveries and tailored advice, we ensure this will not be the bottleneck to reaching improved yields and profitability. Get in touch to talk about how our seedlings can be tailored to your needs.

Our portfolio covers brown, red, and green seaweed species

Brown Varieties

We have extensive experience supplying brown seaweed seedlings, especially kelps (Laminariales), for direct seeding and twine applications. Our strains are sourced from diverse marine environments, partnering with farmers, researchers, and local communities.

We specialise in producing clean, stable kelp gametophyte cultures from spores extracted from fertile tissue. These cultures, propagated under strict controls, are available for regional ocean farming, global land-based cultivation, or research.

The extensive gene bank Hortimare curated over the years enables us to supply many locations on short notice. Our collection currently encompasses more than 7000 unique gametophyte clones of approximately 100 different populations and contains Saccharina latissima (sugar kelp), Alaria esculenta (winged kelp), Laminaria digitata (oarweed), Macrocystis pyrifera (giant kelp), and Undaria pinnatifida (wakame).

For new sites and kelp species, we can deliver the first seedlings within 6 to 24 months, depending on the scope. Throughout our processes, we focus on quality and scale. Our capacity to stabilise the genetic diversity of our cultures enables us to continuously supply cultures representing local populations and support sustainable farming practices.

We are also innovating in cultivating new species, such as Dictyota dichotoma, to expand possibilities in seaweed farming (see New Species Domestication).

Red Varieties

Red seaweeds provide a particular challenge – their diverse and often unique life cycles require protocols developed specifically for each species. At the same time, red seaweeds such as Palmaria palmata and Asparagopsis spp. have gained large commercial interest.

At Hortimare, we have dedicated teams focused on the research and cultivation of several red seaweed species. Our standardised protocols enable us to establish cultures from new locations.

For Palmaria palmata (dulse), we supply free-floating gametophytes for land-based cultivation and seeded twine for ocean farming applications.

We have a close partnership with Greener Grazing for the cultivation of Asparagopsis spp. and have jointly developed protocols for ocean-based twine and direct seeding cultivation of gametophytes. In parallel, we have established techniques for the land-based cultivation of tetrasporophytes.

For ocean-based red seaweed cultivation, it is season-dependent, time sensitive, and labour intensive to set up new cultures. Therefore, it is important to get in touch with us at an early stage if you are considering to order. Land-based aquaculture is more flexible, although knowing ahead of time will enable us to scale up the most suitable strains.

We are further working with Gracilaria spp., Osmundea/Laurencia spp. (pepper dulse). With our extensive experience in controlling life cycles we can also establish protocols for other commercially valuable, novel species (see New Species Domestication).

Green Varieties

From our expanding gene bank, we can supply Ulva spp. starting material for land- and ocean-based cultivation purposes. Additionally, we are beginning to explore other commercially interesting green algae, such as Caulerpa lentillifera (sea grapes) and Codium spp.

In collaboration with Seaweedland, we are laying the groundwork for large scale, land-based cultivation of Ulva. Alongside interest in biomass, its bioremediation potential is attracting attention as a scalable, cost-effective solution. The fast growth can help manage nutrient pollution, especially when combined with other forms of low-trophic aquaculture.

To scale up to volumes that make an impact, and achieve reliable production, we focus on closing of life cycles, selecting for specific traits, and cultivation protocols. Ulva is already in a far developed stage, with many fundaments laid out thanks to dedicated research and innovative farmers all over the world.

For the siphonous green algae, Codium spp. and Caulerpa spp., we currently explore how to best lay the groundwork with frontrunners in cultivation and research, globally. While seeding material for these species is not yet available, you can learn more under New Species Domestication.

Your choice for high quality starting material

Developed by Experts

Proven Track Record
Large International Team
Specialised Expertise
Trust and Open Communication

Advanced R&D

Fundamental Discoveries and
Ongoing Optimisation
Collaborating with Leading Institutes
Specialised Facilities
Transferring Plant Breeding methodologies to seaweed
Practical Mindset
Client Focused

Quality Assured

Four-Eyes-Principle
Built-In Redundancies and Backups
+ 17.000 Quality Checks throughout the Year
Culture Health Checks
Production Capacity Forecasting
Seedling Quantification and Density Control
In-house Outgrowth Validation for Farm Performance