Important, and worth stating up front: all cannabis seeds sold by SeedySide are supplied strictly as collectible souvenirs and for genetic preservation only. Germination and cultivation of cannabis seeds is illegal in the United Kingdom and in Ireland. Nothing in this article is cultivation advice, and we don't provide any. This is an explainer on what the terminology on a seed pack means — no more than that.
With that said, the terminology genuinely is confusing, and if you're building a collection or preserving genetics, it's worth understanding what you're actually looking at.
Why there are different categories at all
Cannabis is dioecious — individual plants are either male or female, unlike most garden plants which carry both parts. That single biological fact is the origin of nearly every term you'll see on a seed pack.
Breeders have spent decades manipulating two variables: which sex a seed will express, and what triggers the plant's transition from vegetative growth to flowering. Feminised, regular and autoflowering are the three answers to those questions.
Regular seeds
The unaltered original. A regular seed comes from a straightforward male-to-female cross and will produce either a male or a female plant, roughly 50/50.
Why they still matter: regular seeds carry the complete, unmanipulated genetic package from both parents. For breeders and preservationists, this is the point — you need males to make new crosses, and you need full genetic diversity to maintain a line over generations. Feminised seeds are a dead end genetically; regular seeds aren't.
The trade-off: you don't know what you're getting until it expresses. For anyone whose interest is purely genetic preservation, that unpredictability is the whole appeal — variation within a line is what selection works on.
Regular lines are also generally closer to a strain's original form, which is why heritage and landrace genetics are usually found as regulars. Browse the regular seeds collection to see what's held.
Feminised seeds
Feminised seeds are bred to produce female plants almost exclusively — typically 99%+.
How they're made: a female plant is treated with a chemical agent (usually colloidal silver or silver thiosulphate) that causes it to produce pollen despite being female. That pollen carries only female chromosomes. Crossing it back to another female produces seeds with no male genetic contribution at all.
Why they dominate the market: predictability. Feminised seeds now account for the large majority of seeds sold worldwide, because most buyers want a known outcome rather than a coin flip.
The genetic trade-off: you can't breed forward with them in the conventional sense. No males means no new crosses without chemical intervention. For a collector, feminised seeds are about the specific expression of a named cultivar rather than the raw genetic material.
The feminised seeds collection is the largest section of our seedbank, which reflects how the market has shifted.
Autoflowering seeds
Autoflowering is a different axis entirely — it describes flowering trigger, not sex.
Most cannabis is photoperiod dependent: it begins flowering in response to changing day length, the same way chrysanthemums or poinsettias do. Autoflowering varieties don't. They transition based on age alone, typically after a set number of weeks, regardless of light cycle.
Where it comes from: Cannabis ruderalis, a hardy subspecies from Central Asia and Eastern Europe, where the growing season is too short and unpredictable for day-length triggering to be reliable. Ruderalis evolved to flower on a timer instead. Modern autoflowers are ruderalis crossed with photoperiod varieties to combine the timing trait with more desirable characteristics.
What this means in practice: autoflowering varieties complete their lifecycle much faster than photoperiod ones, and stay considerably smaller. Historically they were dismissed as inferior — early autos had noticeably lower potency and less complexity. Modern breeding has closed most of that gap, and contemporary autos are a serious category rather than a compromise.
Note that autoflowering and feminised aren't mutually exclusive. Most autoflowering seeds sold today are also feminised — our autoflower collection is largely feminised autos.
CBD seeds
CBD-dominant varieties are bred for high cannabidiol and deliberately low THC.
This is genuinely different genetics, not a processing difference. Whether a plant produces THC or CBD comes down to which enzyme it expresses — THCA synthase or CBDA synthase — and that's inherited. Breeders have selected for CBD-dominant expression to produce varieties with markedly different cannabinoid profiles from conventional cultivars.
Some CBD varieties are bred to fall below legal THC thresholds, which is why industrial hemp cultivars are a related but distinct category. See our CBD seeds collection, and our separate CBD products range for finished goods.
Quick comparison
| Regular | Feminised | Autoflowering | |
|---|---|---|---|
| Sex outcome | ~50% male, ~50% female | ~99%+ female | Usually feminised |
| Flowering trigger | Photoperiod | Photoperiod | Age-based |
| Genetic diversity | Full | Reduced (no male line) | Varies; ruderalis in the background |
| Breeding value | High | Limited | Limited |
| Typical collector interest | Preservation, heritage lines | Named cultivars | Novel traits, ruderalis heritage |
What the numbers on a seed pack mean
THC / CBD percentages. Breeder-reported figures from test conditions. Treat them as an indication of a variety's genetic potential, not a guarantee — expression varies enormously with environment.
Indica / sativa / hybrid. Increasingly a marketing convention rather than a botanical one. Modern cultivars are almost universally hybrids, and the labels correlate poorly with actual chemical profile. Terpene composition is a better guide to a variety's character than the indica/sativa split.
Pack size. Seeds are typically sold in 3, 5 or 10 packs.
Breeder name. Often the most useful thing on the pack. A well-regarded breeder's line will be far more consistent than an unattributed one, which matters if you're preserving genetics.
Storing a seed collection
If you're keeping seeds long term, storage is what determines whether they remain viable genetic material or become inert. The short version: cool, dark, dry, stable, and away from oxygen and humidity swings.
We've covered this in detail in how to store cannabis seeds properly, and you can read about the conditions our own stock is held in at inside our seedbank.
The UK legal position
To be completely clear:
- Buying and possessing cannabis seeds is not an offence in the UK. Seeds themselves contain no controlled cannabinoids in any meaningful quantity and are not scheduled under the Misuse of Drugs Act 1971.
- Germinating or cultivating them is a criminal offence under section 6 of the Misuse of Drugs Act. It carries a maximum of 14 years' imprisonment and an unlimited fine.
- Advertising or supplying seeds with cultivation guidance can constitute incitement, which is why reputable retailers sell strictly on a souvenir basis and don't provide grow information.
- The position in the Republic of Ireland is broadly similar under the Misuse of Drugs Acts.
Laws elsewhere vary significantly and change frequently. If you're ordering to another jurisdiction, check your own local legislation — you are responsible for compliance, not the retailer.
Frequently asked questions
Are cannabis seeds legal in the UK?
Buying and possessing them is legal. Germinating or cultivating them is not, and carries serious penalties.
What's the difference between feminised and autoflowering?
They describe different things. Feminised refers to sex — nearly all female. Autoflowering refers to flowering trigger — age-based rather than light-based. A seed can be both.
Why would anyone buy regular seeds?
Genetic completeness. Breeders and preservationists need males, and regular seeds carry the full unmanipulated genetics of a line.
Do CBD seeds contain no THC?
They're bred for high CBD and low THC, but "low" isn't "none". Cultivars vary and legal thresholds differ by jurisdiction.
How long do cannabis seeds stay viable?
Properly stored, many years. Poorly stored, they degrade quickly. Storage conditions matter more than age.
Is indica vs sativa a real distinction?
Botanically it's contested, and for modern hybrid cultivars it's a poor predictor of anything. Chemical and terpene profiles are more informative.
Our full seedbank is organised by regular, feminised, autoflowering and CBD genetics, with discreet packaging on all orders.
18+ only. All cannabis seeds are sold strictly as collectible souvenirs and for genetic preservation. Germination and cultivation are illegal in the UK and Ireland. SeedySide does not encourage or condone any illegal activity.