Forbidden Runtz Auto by FastBuds – XXL Yields in 9 Weeks | Indica-Dominant Autoflower

Forbidden Runtz Auto by FastBuds delivers XXL yields of resin-drenched, top-shelf buds in just 65 days from seed—no light cycle changes needed, no stress, just pure performance.

Are You Still Waiting Months for Mediocre Harvests?

Most autoflowers leave you choosing between speed and quality. You end up with airy buds, weak flavors, or disappointing yields—especially if you're short on space or experience. It’s frustrating to invest time and effort only to harvest something that doesn’t live up to the hype.

What If You Could Get Runtz-Level Quality on Autopilot?

Imagine opening your grow tent and being hit by a wave of sweet, candy-like terps. Picture buds so dense and frosty they look like they’ve been dipped in diamonds. Now imagine harvesting up to 550 g/m² in under 10 weeks—without any advanced skills. That’s the reality with Forbidden Runtz Auto. No more compromises. No more guesswork. Just consistent, high-caliber results, every single time.

Forbidden Runtz Auto: What You’re Getting

This is the legendary Runtz experience, re-engineered for speed and simplicity. A perfectly balanced indica-dominant hybrid (65% indica, 35% sativa) bred by FastBuds to deliver maximum potency, flavor, and yield with minimal effort.

• Indica 65% / Sativa 35% — best of both worlds
• Up to 26% THC — powerful, balanced effects
• Autoflowering — grows from seed to harvest in 9 weeks
• XXL size — reaches 1.30 m (4.27 ft) tall
• Fruity, sweet, earthy flavor — creamy smoke with citrusy candy aftertaste

How Your Grow Routine Changes Forever

Forget complicated training schedules and nutrient charts. With Forbidden Runtz Auto, you plant the seed and let it do its thing. It grows fast, stays bushy, and develops massive colas with minimal intervention. Indoors, it fills your space with thick, spear-shaped buds coated in trichomes. Outdoors, it thrives in warm to moderate climates, resisting mold and pests like a champ. You’ll spend less time babysitting and more time enjoying the results.

Advantages and benefits you’ll notice from day one

• Harvest in 65 days — faster turnaround than most photoperiods
• Yields up to 550 g/m² (1.21 oz/ft²) — commercial-grade production at home
• Begins flowering automatically — no light cycle switches
• Beginner-friendly genetics — high resistance, low maintenance
• Intense, long-lasting high — cerebral lift followed by full-body melt
• Delicious, complex flavor — no harsh or bland smoke
• Perfect for extractors — resin-rich buds ideal for concentrates

Technical specifications

• Breeder / Brand: FastBuds
• Type: Autoflowering
• Dominance: Indica 65% / Sativa 35%
• Genetics: Forbidden Fruit × Runtz × Autoflowering genetics
• Total cycle: 9 weeks (germination to harvest)
• Indoor yield: 450–550 g/m² (1.0–1.2 oz/ft²)
• Outdoor yield: 60–140 g/plant (2–5 oz/plant)
• Indoor height: 0.85–1.30 m (2.79–4.27 ft)
• Outdoor height: 0.85–1.30 m (2.79–4.27 ft)
• Difficulty: Low
• Structure: Bushy, strong branches, tight internodal spacing
• Climate: Warm to moderate (15–25 °C)
• Resistance: High resistance to mold, pests, and heat stress
• Training: Suitable for LST and light defoliation; avoid topping
• Recommended pot: 18–27 L final pot
• Light cycle: 18/6 or 20/4 (entire cycle)
• THC: Up to 26%
• CBD:
• Flavor: Sweet, fruity, earthy, creamy, citrus
• Effect: Balanced — uplifting start, relaxing finish

How to grow Forbidden Runtz Auto for maximum results

FastBuds’ Forbidden Runtz Auto thrives with minimal fuss but rewards attention to detail. Follow this streamlined guide for top-tier harvests.

Quick overview

Autoflowering · FastBuds · 9-week cycle · Low difficulty · Ideal for indoor, outdoor, or greenhouse.

• Start with a final 18–27 L pot to avoid transplant shock
• Use well-aerated soil or coco with PH Down to maintain balance
• Keep light cycle at 18/6 or 20/4 from seed to harvest
• Begin with low nutrient doses — autos are sensitive

Stable seedling

First two weeks are critical for root development.

• Germinate in moist paper towel or directly in substrate
• Keep RH at 60–70% and temperature at 22–25 °C
• Use Clonex Rooting Hormone Gel for faster, stronger roots
• Water lightly — let topsoil dry between waterings

Directed growth

Weeks 3–5: rapid vertical and lateral expansion.

• Apply LST early to spread canopy and improve light penetration
• Use bamboo stakes or a scrog net for branch support
• Feed with mild nutrients — avoid nitrogen overload
• Ensure good airflow to prevent mold in dense foliage

Efficient flowering

Weeks 6–9: bud development and resin production peak.

• Lower RH to 40–50% to protect dense buds
• Support heavy colas with stakes or netting
• Switch to bloom-focused nutrients like Big Bud Coconut
• Flush with plain water 7–10 days before harvest

Harvest and refinement

Timing is everything for optimal effect and flavor.

• Harvest when trichomes are mostly milky with some amber
• Cut branches and hang upside down at 18–22 °C and 50–60% RH
• Dry for 7–10 days, then cure in jars for 2–4 weeks
• Burping jars daily improves smoothness and flavor

Tips to combine it with other Pevgrow products

Maximize your Forbidden Runtz Auto’s potential with smart product pairings that boost growth, yield, and flavor.

• Start strong with a rooting gel to ensure fast, healthy germination
• Use organic soil enhancers for a richer terpene profile
• Add bloom boosters during flowering for denser, heavier buds
• Pair with carbon filters if growing indoors for discretion
• Invest in quality grinders and storage jars for the full experience

Frequently Asked Questions

Can I top or FIM Forbidden Runtz Auto?

While possible, it’s not recommended. Autoflowers have a fixed life cycle and aggressive pruning can stunt growth. Stick to LST and light defoliation for best results.

How tall does Forbidden Runtz Auto get?

Indoors or outdoors, it reaches 0.85–1.30 m (2.79–4.27 ft), making it ideal for spaces with moderate height.

What’s the best light setup for this strain?

LEDs work great—use 18/6 or 20/4 cycles. Keep lights at a safe distance to avoid light burn while encouraging stretch.

Does it smell during grow?

Yes, the aroma is strong, especially in late flowering. Use a carbon filter or grow in a well-ventilated area for discretion.

Is this strain good for beginners?

Absolutely. It’s forgiving, resistant, and grows consistently with basic care—perfect for first-time growers.

Personal Experience of Pevgrow’s CEO (Alan)

I grew Forbidden Runtz Auto in my personal 1.2 x 1.2 m tent with a 600W LED. Planted three seeds directly in 20L pots—no transplants. I used LST at week 3 to flatten the canopy, and by week 5, the plants were bushy and full. No topping, no stress. In flowering, the smell was unreal—like a candy store exploded. I supported the main colas with bamboo stakes and flushed for 7 days. Harvested at 63 days. Dried slowly and cured for 3 weeks. The buds were rock-hard, frosty, and smelled like sweet citrus. The high? Perfect balance—energizing at first, then deeply relaxing. I’ve grown a lot of autos, but this one’s a game-changer. It’s now in my regular rotation, and I recommend it to anyone who wants quality without the hassle.