Dark Devil Auto

Dark Devil Auto Cannabis Seeds by Sweet Seeds

Dark Devil Auto is a feminized autoflowering cannabis seed from Sweet Seeds that produces plants with striking dark purple to near-black buds — genuinely unlike anything else in your grow room. Created by crossing the heavy-yielding Big Devil XL with an exotic purple autoflowering strain from Buddha Seeds, this cultivar finishes seed-to-harvest in roughly 60 days and delivers 400–600g/m² indoors. If you want a conversation-starting plant that also pulls serious weight at harvest, this is where you start.

Why Dark Devil Auto Seeds Stand Out

About 80% of Dark Devil Auto specimens develop that signature colour shift — flowers moving through dark reddish and purple hues as they mature, with leaves turning purple and, in some cases, buds going genuinely black. We've sold a lot of autoflower seeds over the years, and nothing else in the catalogue looks quite like a finished Dark Devil. The remaining 20% stay green, which is worth knowing upfront so you're not disappointed if one plant in a batch doesn't go full goth.

The genetics behind it are solid. Big Devil XL brings the yield — that 400–600g/m² indoor figure isn't marketing fluff, it's what this lineage was bred for. The Buddha Seeds purple auto parent contributes the colour and a complex terpene profile. The plants develop a strong main stem with numerous side branches, finishing with a chunky central cola surrounded by resin-coated satellite buds. The aroma is fruity with distinct notes of incense and citrus — sweet on the inhale with an almost spicy, resinous undertone that fills the drying room.

The honest limitation: colour expression depends on environment. Cooler night temperatures during late flower (around 15–18°C) push the anthocyanin production that creates those dark hues. If you're growing in a warm climate without temperature control, you'll still get excellent bud, but the colour show might be less dramatic. That's genetics meeting environment — not a defect.

Dark Devil Auto Grow Specifications

How to Grow Dark Devil Auto Seeds

Dark Devil Auto is an autoflowering strain, meaning it flowers based on age rather than light cycle changes. That makes it forgiving for less experienced growers and efficient for anyone wanting a fast turnaround. Here's a practical grow guide based on what works.

1. Germinate your seeds using the paper towel method or directly in a small pot of moist, light soil mix. Tap roots typically emerge within 24–72 hours.
2. Transplant seedlings into their final container early — 11–15 litre pots work well. Autoflowers don't love being transplanted once established, so move them before the third set of true leaves.
3. Run your lights on an 18/6 or 20/4 schedule from seedling through harvest. Dark Devil Auto doesn't need a 12/12 flip. Some growers run 20/4 for the entire cycle to maximise photosynthesis without stressing the plant.
4. Keep feeding light during the first week — water only, no nutrients. From week two onward, introduce a mild vegetative feed. Experienced Dark Devil growers on cultivation forums report that this strain is sensitive to overfeeding; start at half the manufacturer's recommended dose and increase gradually.
5. Watch for the colour transition starting around week 5–6. To encourage darker pigmentation, allow a temperature drop of 5–8°C during the dark period if your setup permits it.
6. Harvest when trichomes are mostly milky with some amber — typically around day 60 from sprout, though some phenotypes may take a few extra days. The dark bud colour can make visual assessment trickier, so a jeweller's loupe or USB microscope is worth having.
7. Dry slowly in a dark room at 18–20°C and 55–60% humidity for 7–10 days, then cure in glass jars for at least 2 weeks. The fruity, incense-like terpene profile develops noticeably during a proper cure.

Dark Devil Auto vs Other Autoflowering Seeds

If you're weighing up Dark Devil Auto against other autoflowers in the Sweet Seeds range or beyond, here's a quick comparison. For pure yield, the Big Devil XL Auto (the parent strain) pushes similar numbers but without the colour show. If you want colour and are willing to trade some yield, the Red Poison Auto from Sweet Seeds offers red and purple hues but typically finishes slightly smaller at 40–150cm. For growers who want a fast, no-nonsense auto without the colour genetics, something like a Northern Lights Auto is more predictable but far less interesting to look at.

Dark Devil Auto hits a sweet spot: it's visually spectacular, yields like a proper production strain, and finishes in 60 days. The best autoflower for growers who want their harvest to look as good as it performs.

What to Expect from Dark Devil Auto Plants

The sensory experience of growing Dark Devil Auto is genuinely unique. During weeks 5–7, the colour transition happens almost visibly day to day — green buds darken through deep red, then purple, and in the most expressive phenotypes, near-black. The resin production is heavy, coating buds and sugar leaves in a frosty layer that contrasts dramatically against the dark flower tissue. When you open the tent during late flower, the smell hits immediately: sweet fruit, something almost churchy (that incense note), and a bright citrus edge that cuts through everything.

The plant structure is compact but productive. Expect a dominant central cola with 4–6 substantial side branches, each carrying dense nuggets. At 80–130cm, it fits comfortably in a standard 120cm tent without training, though low-stress training (LST) during weeks 2–3 can open up the canopy and boost light penetration to those lower bud sites.

One thing we'd flag: the 50–200g outdoor yield range is broad because autoflowers are more dependent on light hours and climate than photoperiod strains when grown outside. In northern Europe, you'll land closer to the lower end unless you're hitting a good summer window. Indoors with proper lighting, the 400–600g/m² is realistic and well-documented by growers across multiple forums.

Frequently Asked Questions

Last updated: April 2026