Jack 47 XL Auto by Sweet Seeds – Tall, High-Yielding Autoflowering Strain for Energetic Effects

Jack 47 XL Auto by Sweet Seeds is a high-yielding, third-generation autoflowering strain that delivers potent sativa-dominant effects and a rich citrus-incense aroma in just 9 weeks from seed to harvest, making it perfect for fast, discreet grows with serious power.

Struggling with weak yields and bland autoflowers?

Most autoflowering strains sacrifice potency and flavor for speed, leaving you with small, airy buds and a forgettable high. You want something that actually hits hard and tastes amazing — without waiting months.

What happens if you keep settling for average autos?

You’ll keep dealing with underwhelming harvests, weak effects, and plants that barely stand out. Worse, you might miss the energizing, creative buzz that only a true sativa can deliver — the kind that fuels your day, not ruins your night.

The solution? Jack 47 XL Auto — big, bold, and built to impress

This isn’t just another auto — it’s a powerhouse. Bred from elite Jack 47 Auto stock through multiple generations of selection, Jack 47 XL Auto grows tall (up to 1.30 m), produces dense, resin-coated buds, and packs a THC punch of 18–21%. You get massive yields, a complex aroma, and a euphoric, stimulating high — all in a plant that flowers automatically.

Why Jack 47 XL Auto dominates your grow space

From first sprout to final cure, this strain is engineered for performance. It’s not just fast — it’s powerful, aromatic, and built for real results.

Massive yields without the wait

• Produces up to 600 g/m² indoors — among the highest yields for autoflowering strains
• Delivers 60–200 g/plant (2.12–7.05 oz/plant) outdoors, even in challenging conditions
• Harvest-ready in just 9 weeks from germination — no timing lights or stress
• Tall structure (0.65–1.30 m / 2.13–4.27 ft) captures more light for bigger colas

Explosive sativa power with a smooth finish

• 76.9% sativa dominance delivers a fast-acting, cerebral high — perfect for daytime creativity
• THC levels of 18–21% ensure a strong, psychoactive experience without sedation
• Sweet, fresh flavor with lemon, citrus, and a hint of incense — smooth on the inhale, unforgettable on the exhale
• Effects are uplifting and energizing, helping you stay focused and social

Grow it like a pro — even if you’re just starting

1. Start seeds in a 1.5 L pot and transplant once to a final 18–27 L container for maximum root development
2. Keep light on 18–20 hours daily — no changes needed, perfect for autoflowering setups
3. Use well-aerated soil or coco; add Coco Kaya 50L Juju Royal Substrate for optimal drainage and growth
4. Apply mild nutrients early; boost with PK 50-30 during mid-flowering for denser buds
5. Support tall plants with stakes if needed, but avoid topping or aggressive pruning

Technical specifications

• Breeder / Brand: Sweet Seeds
• Type: Autoflowering
• Genetics: Jack 47 Auto × Jack 47 Auto (SWS31)
• THC: 18–21%
• CBD: 0.1%
• Indoor Yield: 475–600 g/m² (16.75–21.16 oz/ft²)
• Outdoor Yield: 60–200 g/plant (2.12–7.05 oz/plant)
• Height: 65–130 cm (25.59–51.18 in)
• Harvest Time: 9 weeks from germination
• Flowering Time: Automatic, 63 days
• Difficulty: Low
• Climate: Temperate, Mediterranean
• Resistance: Moderate resistance to mold and pests
• Structure: Tall, branched, vigorous stretch in pre-flowering
• Training: Suitable for LST; avoid topping
• Aroma: Sweet, citrus, lemon, incense
• Effect: Stimulating, psychoactive, uplifting

Frequently Asked Questions

Is Jack 47 XL Auto good for beginners?

Yes. It’s easy to grow, forgiving of minor mistakes, and doesn’t require complex training or lighting schedules.

How tall does it get?

Between 65 and 130 cm (2.13–4.27 ft), making it one of the tallest autoflowers available — ideal for maximizing vertical space.

Does it smell strong during grow?

It has a medium to high odor, especially in late flowering. Use a carbon filter if discretion is a priority.

Can I grow it outdoors in a cold climate?

It thrives in warm, sunny climates but can handle mild temperature drops. Avoid extreme cold or prolonged rain to prevent mold.

Personal Experience of Pevgrow’s CEO (Alan)

I’ve tested a lot of autoflowers, but Jack 47 XL Auto stands out. I grew it in a 25L pot with Coco Kaya and a simple 18/6 light cycle — no fancy tricks. It stretched hard in week 3, so I used low-stress training to spread the canopy. By week 6, it was covered in glistening trichomes. The smell? Like lemon zest and temple incense — absolutely addictive. I harvested at 9 weeks and got over 180g from a single plant. The high is clean, fast, and keeps me moving — perfect for daytime sessions. If you want an auto that smokes like a photoperiod, this is it.