Amnesia Fast
Cannabis seeds
by Advanced Seeds
Amnesia Fast Feminized Cannabis Seeds
Amnesia Fast is a fast-flowering feminized cannabis seed from Advanced Seeds that delivers the full Amnesia Haze experience in just 65–70 days of bloom. Where the original Amnesia Haze can test your patience with flowering times pushing 12+ weeks, this accelerated version shaves off precious days without sacrificing the strain's signature lemon-incense terpene profile or its 18% average THC content. If you've grown Amnesia before and loved everything except the wait, this is the seed you want in your hand.
This product comes in a single pack size: 3 feminized seeds per pack. Each seed is feminized, meaning virtually every plant will flower as a female — no need to sex your crop or waste space on males.
Why Amnesia Fast Seeds Deserve a Spot in Your Grow Room
The original Amnesia Haze is a legend for good reason — that sharp lemon-and-incense aroma, the uplifting sativa effect, the resin production that makes your scissors stick together. But its flowering time has always been the trade-off. We've seen growers get impatient around week 10, chop early, and end up with underdeveloped buds that don't do the genetics justice. Advanced Seeds built Amnesia Fast specifically to solve that problem.
By crossing the original Amnesia genetics with faster-flowering stock, they've pulled the harvest window back to 65–70 days from the flip to 12/12 — roughly 9–10 weeks. That's a solid 2–3 weeks faster than many Amnesia Haze phenotypes. You still get the vigorous, pine-tree-like growth structure, the long dense buds with bulging calyxes, and that thick coat of sticky resin. You just get it sooner.
The honest limitation? A slightly shorter flowering time can occasionally mean marginally less complexity in the terpene profile compared to a 13-week Amnesia Haze pheno that's been allowed to fully ripen. In practice, most growers won't notice the difference — especially if you're dialling in your environment and letting the trichomes reach full maturity before you harvest. The lemon-spice-incense nose on Amnesia Fast is still unmistakably Amnesia.
Amnesia Fast Growing Specifications
| Specification | Detail |
|---|---|
| Seed Bank | Advanced Seeds |
| Seed Type | Feminized (photoperiod) |
| Genetics | Amnesia Haze x fast-flowering hybrid |
| Dominant Type | Sativa-dominant |
| Flowering Time | 65–70 days |
| Indoor Height | 80–100 cm |
| Outdoor Height | Up to 250 cm |
| Indoor Yield | 450–550 g/m2 |
| Outdoor Harvest | Early October |
| THC Content | 18% average |
| Seeds Per Pack | 3 |
Amnesia Fast Aroma and Bud Structure
Crack open a cured jar of Amnesia Fast and the first thing that hits you is lemon — not subtle citrus, but a sharp, almost cleaning-product intensity that tells you the terpene content is serious. Underneath that initial punch, there's a warm layer of spice and a resinous incense quality that lingers on your fingers after handling the buds. It's the kind of smell that sticks to your clothes if you're not careful during trim.
The buds themselves grow long and columnar rather than round — typical of sativa-dominant genetics. They're denser than you'd expect from a sativa, though, with calyxes that swell visibly in the final weeks of flower. Resin coverage is heavy. By harvest, the sugar leaves and bud surfaces are coated in a sticky layer of trichomes that makes Amnesia Fast an excellent candidate for hash or rosin production if you've got trim to spare.
How to Grow Amnesia Fast Seeds
- Germination: Soak your Amnesia Fast seeds in a glass of room-temperature water for 12–24 hours until they sink, then transfer to damp paper towels in a warm, dark spot (20–25°C). Taproots typically emerge within 24–72 hours.
- Seedling stage: Plant the germinated seed 1 cm deep in a light, airy medium. Keep humidity around 65–70% and light intensity low for the first week. Amnesia Fast is a vigorous grower from the start — you'll see rapid leaf development early on.
- Vegetative growth: This strain develops a strong central stem and sturdy side branches with a natural pine-tree structure. Top the main stem once you've got 4–5 nodes to encourage lateral branching and improve light penetration. Amnesia Fast responds well to topping and LST (low-stress training).
- Training and defoliation: Regular pruning and defoliation through veg keeps the canopy open. If you're running a ScrOG setup, Amnesia Fast is a strong choice — its natural stretch during early flower fills a screen nicely. Tuck branches under the net during the first 2–3 weeks of bloom.
- Flowering: Flip to 12/12 when your canopy is 40–50% of your target final height — Amnesia Fast stretches noticeably in early flower. Expect 65–70 days from the flip to harvest. Indoor plants typically stay between 80–100 cm; outdoors, they can reach 250 cm in good conditions.
- Harvest timing: Check trichomes with a jeweller's loupe from day 60 onwards. You're looking for mostly cloudy trichomes with 10–20% amber for a balanced effect. Outdoor growers in northern Europe should plan for an early October harvest.
- Drying and curing: Hang whole plants or individual branches in a dark room at 18–20°C and 55–60% humidity for 10–14 days. Cure in sealed glass jars, burping daily for the first two weeks. The lemon-incense terpene profile develops noticeably during a proper 3–4 week cure.
Amnesia Fast vs Original Amnesia Haze Seeds
Here's the straight comparison.
| Trait | Amnesia Fast | Original Amnesia Haze |
|---|---|---|
| Flowering Time | 65–70 days | 80–90+ days |
| THC | 18% average | 18–22% (pheno-dependent) |
| Indoor Height | 80–100 cm | 100–150 cm |
| Indoor Yield | 450–550 g/m2 | 500–650 g/m2 |
| Aroma Profile | Lemon, spice, incense | Lemon, spice, incense (slightly more complex in top phenos) |
| Training Response | Excellent — tops and ScrOGs well | Excellent — but needs more vertical space |
| Best For | Growers who want Amnesia flavour on a tighter schedule | Growers with time, space, and patience for maximum expression |
If you've got a height-limited tent and want to run multiple cycles per year, Amnesia Fast is the better pick. If you've got a tall space and don't mind waiting, the original Amnesia Haze can push slightly higher THC in the right hands. Both are excellent — it comes down to your setup and your schedule.
Complete your grow: Pair Amnesia Fast with a ScrOG net to make the most of its natural stretch and branching structure. If you're growing indoors, a proper carbon filter is non-negotiable once these plants hit mid-flower — that lemon-incense terpene profile is loud. Check out our grow tents and ventilation kits to set yourself up properly from the start.
What Makes Amnesia Fast a Smart Pick
Running multiple indoor cycles per year is how you maximise your output from a single tent. Every extra week of flowering is a week you're not starting your next run. With Amnesia Fast finishing in 65–70 days, you can realistically fit in an extra full cycle per year compared to the original Amnesia Haze. Over 12 months, that adds up to significantly more harvested weight from the same square metre.
There's also the practical side of growing sativa-dominant strains indoors. Classic Amnesia Haze can stretch well past 100 cm, which creates headroom problems in standard 180 cm tents once you account for pots, lights, and the gap you need between canopy and lamp. Amnesia Fast stays more compact at 80–100 cm indoors, giving you breathing room without sacrificing the sativa character you're after. We'd pick this over the original for any tent under 200 cm tall.
For outdoor growers in northern Europe, the early October harvest window is another genuine advantage. Late-finishing sativas are a gamble in climates where autumn rain and cold arrive by mid-October. Getting your crop down a few weeks earlier can be the difference between a clean harvest and a mould problem.
Frequently Asked Questions
How long does Amnesia Fast take to flower?
Amnesia Fast flowers in 65–70 days from the switch to 12/12 lighting. That's roughly 9–10 weeks — about 2–3 weeks faster than the original Amnesia Haze, which typically needs 80–90+ days.
What is the THC content of Amnesia Fast?
Advanced Seeds lists Amnesia Fast at 18% THC on average. Actual levels depend on your growing conditions, light intensity, and how well you dial in the late-flower environment. Proper curing also helps preserve cannabinoid and terpene content.
Is Amnesia Fast suitable for indoor growing?
Yes — it's actually one of the better Amnesia variants for indoor setups. Plants stay between 80–100 cm, which fits comfortably in standard grow tents. It responds well to topping, LST, and ScrOG techniques, and yields up to 450–550 g/m2 indoors.
Can I grow Amnesia Fast outdoors in northern Europe?
Absolutely. Amnesia Fast is ready for outdoor harvest in early October, which gives you a decent window before autumn weather turns nasty. Plants can reach up to 250 cm outdoors in good conditions, so factor in the height if you need discretion.
What does Amnesia Fast smell like?
Strong lemon up front — sharp and unmistakable. Behind that, there's warm spice and a resinous incense quality. It's a loud strain in late flower, so run a carbon filter indoors unless you want the whole building to know what you're up to.
Does Amnesia Fast need training or can I let it grow naturally?
You can grow it untrained, but you'd be leaving yield on the table. Topping the main stem at 4–5 nodes and running a ScrOG or LST setup makes a noticeable difference. The strain's natural stretch and branching structure respond brilliantly to training techniques.
How does Amnesia Fast compare to other fast-flowering Amnesia seeds?
Advanced Seeds has a solid reputation for stable genetics, and their Amnesia Fast keeps the original's terpene profile intact — something cheaper fast-flowering crosses sometimes lose. At 18% THC and 450–550 g/m2, it sits comfortably in the top tier of accelerated Amnesia strains available.
Last updated: April 2026
Related products
You might also like
Medical disclaimer. This content is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider before use of any substance.