Black Muffin F1 Fast Version® Feminized Seeds – Sweet Seeds® · Fast-Flowering Photoperiod with Red & Purple Buds

Black Muffin F1 Fast Version® by Sweet Seeds® is a photoperiod feminized strain that delivers vibrant red and purple flowers in just 7 weeks of flowering, combining speed, potency, and stunning visuals in one elite plant.

Stuck in slow-growth mode with weak yields and bland flavors?

You’ve tried fast strains before, but they lacked punch, aroma, or visual appeal. Maybe your setup feels underused because you’re waiting weeks too long for harvest. Or perhaps you’re chasing that perfect balance of creativity and calm, but your current genetics fall flat.

Waiting months for average buds? That’s yesterday’s grow.

Most fast-flowering strains sacrifice quality for speed. They deliver bland flavors, weak effects, or spindly plants that barely fill the space. And if you're aiming for colorful, resin-drenched buds, you’re usually told to wait 9+ weeks. That’s time you don’t have — and flavor you’re missing out on. The frustration of underwhelming harvests kills motivation, especially when you know your setup could do more.

Meet the hybrid that redefines fast: red flowers in 7 weeks, zero compromise.

Black Muffin F1 Fast Version® is the answer — a photoperiod strain bred from Red Hot Cookies® and Black Lemon Auto that delivers intense citrus-fruit flavors, THC up to 25%, and thick, purple-tinged buds soaked in resin. It’s not just fast; it’s elite. With hybrid vigor, it grows strong, bushy, and resilient, turning your grow space into a high-yield, high-flavor zone without cutting corners.

If you’re just starting out: this strain grows like a dream

No green thumb needed. Black Muffin F1 Fast Version® is forgiving, predictable, and rewards basic care with serious results. It handles common mistakes like slight overwatering or light stress, making it perfect for your first high-performance strain.

• Flowers in just 7 weeks — ideal for quick cycles
• Sturdy structure resists stretching and mold
• Low-maintenance feeding — thrives in soil or coco
• Produces colorful buds even in beginner setups
• Sticky resin means high potency with minimal effort

If you already have experience: unlock next-level control and flavor

Advanced growers, this one’s built for tinkering. Train it with LST, SCROG, or light topping to maximize yield. Push nutrients in mid-flower for denser buds, or tweak the environment to intensify those red and purple hues.

• Responds well to LST and defoliation for even canopy
• Thrives under high-intensity lighting (HPS, LED)
• Develops deeper purple and red pigments with cooler temps
• Resin production increases with proper PK boost
• Perfect for resin extraction or premium flower

Advantages and benefits for any level

• Fast 7-week flowering — harvest sooner, grow more cycles
• High THC (17–25%) with balanced, uplifting, and relaxing effects
• Sweet-sour citrus aroma with lemon, mandarin, and forest fruit notes
• Produces 500–600 g/m² indoors or 400–600 g/plant outdoors
• 60% Indica dominance for strong, compact growth
• Approx. 60% of plants develop red or deep purple flowers
• Resin-rich buds ideal for smoking, vaping, or extracts
• Perfect for social moments, creativity, or unwinding

Typical mistakes this product helps you avoid

Even experienced growers slip up. But this strain’s resilience and clear signals keep you on track.

• Overwatering — its vigorous root system tolerates slight errors
• Weak yields — hybrid vigor ensures high production
• Bland flavor — complex terpene profile delivers intense taste
• Long waits — 7-week bloom gets you harvest-ready fast
• Colorless buds — natural anthocyanin expression creates purple tones
• Low resin — sticky flowers form early and abundantly

Technical specifications

• Breeder / Brand: Sweet Seeds®
• Type: Feminized photoperiod
• Genetics: Red Hot Cookies® × Black Lemon Auto
• Dominance: 60% Indica / 40% Sativa
• Indoor flowering: 7 weeks
• Indoor yield: 500–600 g/m² (17.6–21.2 oz/ft²)
• Outdoor yield: 400–600 g/plant (14.1–21.2 oz/plant)
• Indoor height: approx. 80–110 cm (2.62–3.61 ft)
• Outdoor height: approx. 1.20–1.50 m (3.94–4.92 ft)
• THC: 17–25%
• CBD: approx. 0.1%
• Difficulty: Low to medium
• Structure: Well-branched, compact, vigorous
• Aromatic profile: Limonene, myrcene, pinene (citrus, fruit, slight acidity)
• Flavour: Sweet and sour, lemon, mandarin, red berries
• Effect: Balanced — stimulating, creative, relaxing
• Best for: Indoor and outdoor grows, fast cycles, flavor lovers

How to grow Black Muffin F1 Fast Version® for maximum results

Get the most out of this fast-flowering powerhouse with a simple, effective approach tailored to its hybrid vigor and photoperiod speed.

Quick start: Germinate in a moist environment at 22–25 °C and high humidity. Transplant carefully once the taproot is ~1 cm long.

• Use a well-aerated substrate like Premium Coco Substrate Pre-Fertilized Plagron for strong root development
• Keep pH between 6.0–6.5 (soil) or 5.8–6.2 (coco)
• Start with low EC and increase gradually as the plant grows
• Provide 18/6 light cycle during vegetative stage

Controlled growth: Focus on structure and resilience in the first 3–4 weeks.

• Apply light LST to open the canopy and improve light penetration
• Use SeedBooster Plus germination stimulator for faster, stronger starts
• Water when the top layer of soil feels dry — avoid overwatering
• Ensure good airflow to prevent humidity buildup

Flowering boost: Switch to 12/12 light to trigger bloom — expect color and resin fast.

• Reduce humidity to 40–50% in mid to late flowering
• Support heavy branches with soft ties or trellis net
• Use a bloom booster like Blossom Blaster from week 3 for denser buds
• Monitor trichomes — harvest when milky with some amber for balanced effects

Harvest & cure: Time it right for maximum flavor and smoothness.

• Flush 7–10 days before harvest to improve taste
• Dry slowly at 18–20 °C and 50–60% RH
• Cure in glass jars for 2–4 weeks, burping daily
• Store in a cool, dark place for long-term preservation

Frequently Asked Questions

How long does Black Muffin F1 Fast Version® take to flower?

It flowers in just 7 weeks under 12/12 light, making it one of the fastest photoperiod strains available.

Does it really turn red or purple?

Yes — approximately 60% of plants develop red or deep purple hues during flowering, especially with cooler nighttime temperatures.

Is it suitable for beginners?

Absolutely. It’s forgiving, grows fast, and delivers consistent results with basic care.

Can I grow it outdoors?

Yes. It thrives in warm, sunny climates and can produce up to 600 g/plant with proper nutrition and sunlight.

What kind of effect does it have?

It delivers a balanced high — uplifting and creative at first, then gently relaxing, perfect for socializing or creative projects.

Personal Experience of Pevgrow’s CEO (Alan)

Let me tell you, Black Muffin F1 Fast Version® is a game-changer. I’ve grown dozens of fast strains, but this one? It’s different. I gave it to a friend who was stuck on autoflowers — he wanted more control, better flavor, and something that looked the part. After 7 weeks, he called me, stunned. His plants were purple, sticky as glue, and smelled like a fruit market on fire. For me, I ran it under LED with a tight 18/6 veg — just 3 weeks — then flipped. I used light LST and a touch of Blossom Blaster. The buds were dense, frosty, and burned clean. What I love most is how it bridges the gap: beginners get amazing results without stress, and experts can push it further. It’s not just fast — it’s premium. If you’re tired of waiting or underwhelmed by your harvests, this strain will remind you why you started growing.