As well, just because two breeders have strains of the same or similiar names it does not mean the two strains will grow, taste/smell, or give the same effect. Sometimes that's OK, you're still getting good genetics just not what you thought you ordered. Sometimes you don't get what you think you're getting and may wish you didn't get the seeds at all.
The requisite example of a good difference is Bubblegum. The origional genetics came from America to Europe and the breeders from TH and Serious Seeds got some seeds and inbreed the plants only. TH developed the indica pheno with a euphoric stone, and Serious the sativa pheno with a euphoric high. Both great, both from the same genetics, but different effects.
On the bad side you could buy from a company like Nirvana, who make cheap knock offs and slap a similiar name to a Cup winner. A good example is Serious Seeds AK47, CC winner, one hit rocket high --- vs --- Nirvana AK48: an indica stone. Bad but not horrible because you still may get decent genetics, just not the effect you want.
On the horrible end you could buy from an F2 seed producer who sells unstable cheaply produced seeds. Seeds you could make yourself if you run only one strain and leave the males in your flower room. Plants from these seeds can hermie for no reason, not ripen or finish, unmanagable stretch, low potency ... These are seeds that you'd have been better off paying for and not receiving than putting them in your garden.
So ... go to the Seedbank and Strain review section and pick good breeders you can trust. You can get a single White Widow feminized seed by Green House Seeds for $10.41 CAD at the Pick 'n Mix, take lots of clones and have a garden full of great plants. Great genetics are so cheap there's no reason to buy anything but the best seeds your first time out.
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