Genetics
Cannabis is a single species of flowering plant, though it has two primary varieties within that species, Indica and Sativa, whose effects differ.Indica strains tend to provide sedative or relaxing effects and are often used therapeutically to treat chronic pain, insomnia, muscle spasm, and anxiety. The genetics of indica strains often include a higher concentration of CBD than sativa strains, which contributes to its sedating effects as well as having less intense psychoactive effects. Some common indica cannabis strains include Northern Lights, Afghani, Blueberry, and Chemo.
Sativa strains come with more stimulating effects and are popular to use medically as an anti-depressant, for migraines, for chronic pain, for nausea, and to stimulate appetite. Sativas typically have a higher concentration of THC than indica strains, causing more intense psychoactive effects, increased alertness and energy in the mind, and feelings of optimism. The higher THC-concentration is also connected to increased anxiety in some cases. Common sativa strains include Sour Diesel, Durban Poison, Jack Herer, and Super Lemon Haze.

Sensi Seeds
Amsterdam-based Sensi Seeds is a highly-regarded breeder that has been recognized by experts from Harvard Medical School. Sensi Seeds is particularly noted for its medicinal strains, but all of their seeds are considered quality and reliable, with consistently positive reviews.
Popular stains coming from Sensi Seeds include Super Skunk, Big Bud, and Skunk #1. They also offer a variety of seeds that are great for beginners and some that have won awards as well.
CBD Crew
The seeds coming from CBD Crew are primarily medical. Their goal is to achieve a 1:1 ratio of CBD:THC in all of their strains. While that is still in the works, their current strains have high concentrations of CBD meant to treat a variety of medical conditions and symptoms. They use tested and accurate science to get the optimal results from their products.
CBD Crew is based in Barcelona, Spain. Their focus is CBD seeds, some of which include CBD Kush, CBD Mango Haze, and CBD Critical Mass.
Humboldt Seeds
From Buckingham, England is the quality breeding source known as Humboldt Seeds. Their breeding focus is quality over quantity in order to ensure they are producing top-notch seeds.
The newest addition to the Humboldt Seeds collection, which already included feminized, autoflower, and CBD seeds, now includes what they call “fast seeds,” which are said to flower extremely quickly.
Royal Queen Seeds
Royal Queen Seeds is a breeder that has been in the industry for more than 20 years. Based in Amsterdam, Royal Queen Seeds are competing to be a leader in the market. Their large selection of every kind of seed, all quality and at reasonable prices, just might help them reach their goal.
BC Bud Depot
BC Bud Depot, based in Amsterdam, is a quality breeder known for having some autoflowering seeds that are hard to find. They’ve become a household name for cannabis users in the Netherlands, their reputation stemming from them being one of the best breeders out there.
Their most famous seeds are Girl Scout Cookies, Sweet Tooth, and their very own BC Bud Depot Sweet God.
Jordan of the Islands
Founded in 1992, Jordan of the Islands, based in British Columbia, Canada, offers quality seeds for recreational and medical cannabis users alike. Their goal is to breed seeds that are not only high-yielding and flavorful but pest-resistant as well.
Their namesake, Jordan of the Island God Bud is known for intensely relaxing effects. It has served as a great based for other stains as well.
Dutch Passion
Dutch Passion is a breeder based in Amsterdam who not only sell top-quality seeds but growing and consumption equipment as well. They offer lots of autoflower, feminized, and CBD strains and have lots of customer reviews behind their brand.
One interesting thing about Dutch Passion is their dedication to their clients. Their website is proof of that, providing informative blog posts, photography contests, and a whole cannabis community.