Availability
What is available now, and what is not
California has seaweed seed production. What it does not have is a market in seed. This matrix separates the two, honestly, with a source on every row.
- Available now
Documented as obtainable now, subject to contacting the source.
- Seasonal
Produced in a specific window; timing decides whether you get it.
- Research only
Exists, but supplied under a research or restoration agreement.
- Not available in CA
Produced in-house only, or not offered to outside growers.
- Unconfirmed
We could not confirm it from a public source.
Bull kelp
The most advanced species for California seed research: active gametophyte banking, seeded twine trials in Humboldt Bay, and tribal restoration programs on the North Coast.
Nereocystis luetkeana
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Cal Poly Humboldt — Fisheries Biology / ProvidenSeaNorth Coast | gametophyte culture | Research only | Cultures maintained year round | Arranged per project |
| Cal Poly Humboldt — Fisheries Biology / ProvidenSeaNorth Coast | seeded twine | Research only | Winter to spring outplanting in Humboldt Bay | Arranged per project |
| Sunken SeaweedStatewide | seeded twine | Seasonal | Humboldt Bay hatchery and nursery, seasonal | Contact company |
| Moss Landing Marine Laboratories — Aquaculture FacilityCentral Coast | gametophyte culture | Research only | CLASH project runs through 2026 | Arranged per project |
| Bull Kelp Gametophyte Bank — Alberto Lab / California Sea GrantNorth Coast | gametophyte culture | Research only | Conservation bank, restoration use | By agreement |
| Tolowa Dee-ni' Nation — Kelp GuardiansNorth Coast | gametophyte culture | Research only | Program runs 2024 to 2026 | By agreement |
| North Coast Kelp Recovery ConsortiumNorth Coast | outplanting stock | Research only | Restoration experiments | By agreement |
| Jamestown S'Klallam Tribe — kelp spore preservationOut of state | preserved spores | Research only | Washington restoration program | By agreement |
Giant kelp
The only species with a permitted commercial-scale offshore farm in California. Seed is produced in-house for that farm.
Macrocystis pyrifera
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Ocean Rainforest Inc.South Coast | seeded line | Not available in CA | Produced for own offshore farm | Not offered |
Winged kelp
Experimental seed production only, using a germplasm approach in bioreactor work at Cal Poly Humboldt.
Alaria marginata
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Cal Poly Humboldt — Fisheries Biology / ProvidenSeaNorth Coast | gametophyte culture | Research only | Experimental germplasm work | Arranged per project |
Sea lettuce
Farmed commercially at small scale. Hatchery culture demonstrated through the CLASH hatchery technology project.
Ulva spp.
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Sunken SeaweedStatewide | hatchery nursery stock | Available now | Year round land-based culture | Contact company |
| Monterey Bay SeaweedsCentral Coast | tank culture stock | Not available in CA | Live product sold, seed not offered | Not offered |
| Moss Landing Marine Laboratories — Aquaculture FacilityCentral Coast | research culture stock | Research only | CLASH project runs through 2026 | Arranged per project |
Dulse
Grown in land-based tanks and sold as live product. Culture stock appears to be maintained in-house.
Devaleraea / Palmaria spp.
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Monterey Bay SeaweedsCentral Coast | tank culture stock | Not available in CA | Live product sold, seed not offered | Not offered |
Ogo
Grown in land-based tanks in Monterey Bay. No published third-party seed source.
Gracilaria spp.
| Source | Seed form | Status | Season | Lead time |
|---|---|---|---|---|
| Monterey Bay SeaweedsCentral Coast | tank culture stock | Not available in CA | Live product sold, seed not offered | Not offered |
Producing seed and not listed here?
Claim your listing in the hub and keep your own availability current. That is what turns this from a snapshot into an inventory growers can plan a season around.
Open the hub