Green House Seed Company

What it is

Green House Seed Company is a Netherlands-based cannabis seed producer tied to the Green House coffeeshop chain in Amsterdam. The seed company sells feminized, regular, and autoflowering seeds through its own website and a network of authorized resellers^[1]. It shares branding and personnel with the Green House coffeeshops and with Arjan Roskam's 'Strain Hunters' media project, which documents landrace collection trips^[2].

The company markets itself as 'the most awarded' seedbank in the world, a claim built primarily on High Times Cannabis Cup results from the 1990s and 2000s^[3] Disputed. That tagline is marketing shorthand; there is no independent registry of seedbank awards, and rival Dutch banks (Sensi Seeds, Dutch Passion, Serious Seeds) make overlapping historical claims.

History and ownership

Arjan Roskam opened the first Green House coffeeshop in Amsterdam in 1985^[2]. The seed company grew out of the coffeeshop's in-house breeding work during the 1990s, alongside collaborations with breeder Franco Loja, who became the public face of the Strain Hunters expeditions until his death in 2017^[4].

Ownership has not been the subject of detailed public reporting beyond Roskam's role as founder and public figure. The company is privately held and does not publish audited financials. Independent verification of current corporate structure, breeding staff, and seed production facilities is limited to what the company itself publishes and to interviews in cannabis and mainstream press^[2][4].

Catalogue and genetics focus

Green House's catalogue centers on hybrids the company either bred or helped popularize, including White Widow, Super Silver Haze, Hawaiian Snow, Arjan's Haze #1/#2/#3, Great White Shark, and Neville's Haze^[1]. Several of these strains — notably White Widow and Super Silver Haze — are foundational to modern hybrid genetics, though their exact parentage and who bred them first is contested between Green House, Shantibaba (Mr. Nice Seeds), and other 1990s Dutch breeders^[5] Disputed.

The Strain Hunters project sourced landrace material from Malawi, India, Colombia, Morocco, Swaziland, and other regions, some of which has been incorporated into commercial releases^[2]. How faithfully modern seed batches reproduce the original prize-winning phenotypes is a common point of grower complaint on forums; there is no controlled data on batch-to-batch consistency.

Reputation and awards

Green House genuinely accumulated a large number of High Times Cannabis Cup placements between roughly 1994 and 2010, including cup wins for White Widow, Super Silver Haze, Hawaiian Snow, Arjan's Haze, and others^[3]. High Times published these results contemporaneously, so the historical record is verifiable^[3].

Caveats worth stating plainly:

• The Cannabis Cup has faced criticism over judging, pay-to-enter categories, and its later commercial restructuring^[6][evidence:reported]. Awards from different eras are not directly comparable.
• Winning a cup with a specific plant in a specific year does not mean current seed stock produces the same plant.
• 'Most awarded' is a marketing claim, not an audited statistic.

Grower reviews on independent seed databases and forums are mixed: some report strong results and stable genetics, others report inconsistent phenotypes and hermaphroditism in feminized lines Anecdote. Anecdotal reports are not a substitute for controlled data, and no such data exists publicly.

Controversies and uncertainty

The most persistent controversy involves disputed authorship of key strains. Shantibaba, who worked with Green House in the mid-1990s before founding Mr. Nice Seeds with Neville Schoenmakers and Howard Marks, has publicly claimed he bred White Widow and other lines credited to Green House^[5] Disputed. Green House disputes this account. There is no neutral arbiter for breeder credit in cannabis, and both sides have their supporters.

Arjan Roskam himself is a polarizing figure in the Dutch scene, praised for building an internationally recognized brand and criticized for aggressive self-promotion^[2][4]. Franco Loja's death in 2017 from cerebral malaria contracted on a Strain Hunters trip to Colombia drew significant coverage^[4].

No major regulatory action against the seed company has been publicly reported, though Dutch coffeeshop operators generally have operated in the gedoogbeleid ('tolerance policy') gray zone^[7].

Availability and legal notes

Cannabis seeds are sold in the Netherlands as novelty or collector items under the country's tolerance policy; germination and cultivation are separately regulated^[7]. Green House distributes internationally through its website and resellers, but the legality of importing, possessing, or germinating cannabis seeds varies widely by jurisdiction and can change. In many countries seeds are legal to possess but not to germinate; in others they are fully prohibited; in some US states and Canadian provinces they are sold in licensed retail. Buyers are responsible for knowing their local law.

Weedpedia does not endorse purchase and does not provide shipping, stealth, or germination guidance.

What to verify before ordering

If you are researching Green House as a potential source, independent verification points include:

• Official channels. Confirm you are on the actual Green House Seed Company site or an authorized reseller, not a lookalike domain. Counterfeit seed sites impersonating major Dutch banks are common[evidence:reported].
• Current activity. Check that the site is actively updated and that customer support responds. Company activity status can change; this profile was last checked in 2024.
• Local legality. Verify seed import and possession rules in your jurisdiction before any transaction.
• Strain provenance. If a specific strain's history matters to you (for example, White Widow lineage), read multiple breeder accounts rather than one company's marketing.
• Reviews across sources. Cross-reference recent grower reports on independent databases; weight controlled information over forum anecdote.

Weedpedia cannot confirm seed viability, shipping success rates, or phenotype stability for any seedbank, including this one.

Sources

How this page was made

Related

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