White Widow Auto

White Widow Auto Cannabis Seeds by Greenhouse Seeds

White Widow Auto is an autoflowering feminised cannabis seed from Greenhouse Seeds that delivers the legendary White Widow genetics in a fast, low-maintenance format. No light schedule fiddling, no calendar anxiety — she grows on her own clock and rewards you with 600g/m² indoors after just 7 weeks of flowering. If you've ever wanted to grow a genuine classic without the fuss, this is where you start.

Why White Widow Auto Seeds Deserve a Spot in Your Grow

White Widow has been a coffeeshop staple since the mid-1990s. Walk into any shop on the Haarlemmerstraat and you'll still see her on the menu — that should tell you something about staying power. The original photoperiod version demands a strict 12/12 light flip and a fair bit of patience. This autoflowering version from Greenhouse Seeds strips away that complexity. You plant, you water, you wait roughly 7 weeks from the start of flower, and you harvest dense, resinous buds that carry the same White Widow punch.

We've seen a lot of autoflowering strains come through the shop over the years, and the early generations were — honestly — a bit underwhelming. Airy buds, modest potency, not much to write home about. Modern autos have closed that gap dramatically, and White Widow Auto is a solid example. Greenhouse Seeds crossed the original White Widow mother with a ruderalis line and then backcrossed until the potency and resin production held up. The result is a plant that stays compact at 70–80cm outdoors but still pushes out roughly one gram of dried bud per centimetre of height. Do the maths: that's 70–80g per plant outdoors with minimal effort.

The one thing to watch out for — and we mention this because we've heard it from growers — is branch support in late flower. The buds on White Widow Auto can get properly fat and heavy with resin. Without a bamboo stake or some plant yo-yos, branches can bend or snap under their own weight. It's a good problem to have, but it's still a problem if you're not prepared.

White Widow Auto Specifications

Growing White Widow Auto Seeds — What to Expect

The beauty of autoflowering genetics is simplicity. White Widow Auto doesn't care whether she gets 12 hours of light or 20 — she'll start flowering based on age, not photoperiod. That said, more light generally means more yield, so indoors we'd run 18 hours on and 6 off for the best balance of growth and electricity costs. Some growers push to 20/4 or even 24/0, but the returns diminish and your energy bill doesn't.

Outdoors, this strain handles cooler climates surprisingly well. As long as night temperatures stay above 10°C, she'll thrive. That opens up growing in northern Europe, the UK, and Scandinavia during summer months — places where photoperiod strains often struggle to finish before autumn rain sets in. A balcony, a garden corner, even a sunny windowsill can work for a single plant.

One honest limitation: autoflowers don't give you recovery time. If you stress the plant early — overwater, overfeed, or damage the roots during transplant — she can't "pause" vegetative growth the way a photoperiod plant can. The clock is ticking from germination. Our advice: start in the final pot (11–15 litres), use a light and airy growing medium, and go easy on nutrients for the first two weeks. White Widow Auto isn't fussy, but she doesn't forgive early mistakes as easily as a photoperiod strain would.

How to Grow White Widow Auto Seeds

1. Germinate: Soak seeds in a glass of water for 12–24 hours until they sink, then transfer to a damp paper towel in a warm, dark spot. Taproots should appear within 24–72 hours.
2. Plant directly into the final pot: Use an 11–15 litre container with well-draining soil or coco. Plant the germinated seed 1cm deep, taproot pointing down. Autoflowers dislike transplanting, so skip the seedling pot stage.
3. Seedling phase (weeks 1–2): Keep humidity around 65–70% and temperature at 22–25°C. Water sparingly — a spray bottle is enough. No nutrients yet; the soil has plenty.
4. Vegetative growth (weeks 2–4): The plant will stretch and develop its structure. Start light feeding with a grow nutrient at half the recommended strength. Indoors, maintain an 18/6 light cycle.
5. Flowering (weeks 4–11): White Widow Auto will transition to flower automatically around week 4. Switch to bloom nutrients. Watch for the buds fattening up — by week 6–7 of flower, you'll likely need bamboo stakes or plant yo-yos to support heavy branches.
6. Late flower and harvest: When 70–80% of trichomes turn milky (use a jeweller's loupe or USB microscope), she's ready. Flush with plain water for the final 5–7 days if growing in soil. Cut, trim, and hang to dry at 18–20°C and 55–60% humidity for 7–10 days.

White Widow Auto vs Photoperiod White Widow

If you're weighing up the auto version against the original photoperiod White Widow, here's the honest comparison. The photoperiod version can yield more per plant — she grows taller, bushes out further, and you control when she flowers by flipping to 12/12. But she also takes longer (8–9 weeks of flower after however long you veg) and demands a light-tight environment with a timer. White Widow Auto trades some of that ceiling yield for sheer convenience: 600g/m² indoors in about 11 weeks from seed to harvest, no light schedule management, and a compact plant that fits in tight spaces.

For a first grow, or for anyone growing outdoors in a climate with short summers, the auto version is the smarter pick. If you've got a dedicated indoor setup with proper light control and you want to maximise every gram, the photoperiod White Widow still has the edge. Both carry the same resin-heavy, potent genetics — the difference is in how much effort you want to put in.

Frequently Asked Questions

Last updated: April 2026