Auto MAC Dawg XXL by Silent Seeds – High-Yielding Autoflower with 29% THC · Diesel & Kush Flavor

MAC Dawg XXL Auto by Silent Seeds redefines what’s possible in autoflowering cannabis—delivering photoperiod-level potency, structure, and resin production with the speed and simplicity of an auto. This is next-gen growing, simplified.

Is your grow space full of weak autos and messy harvests?

Most autoflowering strains promise big but deliver small: weak flavors, low yields, and plants that collapse under their own weight. You end up with bland buds, wasted time, and the same old routine—germinate, wait, trim, repeat—without real excitement or results.

Why keep struggling with underperforming autos?

Imagine watching your plants stretch weakly, fail to branch, or rot from mold because they can’t handle real conditions. You’re stuck choosing between speed and quality. And when harvest finally comes, the flavor’s flat, the high is forgettable, and you wonder if it was worth it. That’s the old standard—and it’s holding you back.

Meet the auto that grows like a photoperiod and hits like a legend

MAC Dawg XXL Auto changes everything. Born from Chemdawg Bx1 × MAC Auto, it grows fast but builds like a champion: thick stems, tight internodes, and a bushy structure that supports massive, trichome-drenched colas. Indoors, it yields up to 650 g/m² (2.2 oz/ft²); outdoors, over 400 g/plant (14 oz). With THC up to 29%, the effect is deep, physical, and long-lasting—perfect for unwinding after a long day. The flavor? A punchy mix of diesel, kush, pine, and lemon that lingers on the palate. This isn’t just another auto—it’s a statement.

How your grow space transforms with MAC Dawg XXL Auto

From day one, this plant commands attention. It grows fast and uniform, filling your tent or garden with a dense, bushy presence. No more spindly stems or empty lower branches. The structure supports heavy flowering sites without staking, and the compact size—up to 1.40 m (4.59 ft)—makes it ideal for stealth grows. Whether you're in soil or hydro, indoors or outdoors, MAC Dawg XXL Auto turns chaos into control, delivering elite results without elite effort.

What you can grow with MAC Dawg XXL Auto

• Massive, resin-coated buds perfect for smoking or extraction
• Dense colas that respond well to light training (LST)
• High-THC material ideal for concentrates and edibles
• Plants with strong mold resistance in humid environments
• Consistent phenotypes for commercial or personal harvests
• Fast cycles—ready in 58–63 days from seed to harvest
• Discreet, compact plants ideal for small spaces or balconies

Steps to build your high-performance auto setup

1. Start with a final pot of 18–27 L (6.3–7.1 gal) to avoid transplant stress
2. Use a well-aerated substrate like Kit Top Grow Box Bio for strong root development
3. Apply root boosters like Bio Rhizotonic early for faster establishment
4. Keep 18–20 hours of light daily and maintain 22–26 °C (71.6–78.8 °F) in veg
5. Support heavy colas with soft ties during mid-flowering
6. Flush nutrients 7–10 days before harvest for a smoother taste
7. Harvest when trichomes turn mostly milky with amber hints for full-body effects

Advantages and benefits of elite autoflower performance

• Up to 650 g/m² (2.2 oz/ft²) indoors—rivaling photoperiod strains
• THC up to 29% for intense, long-lasting relaxation
• Complex terpene profile: diesel, kush, pine, lemon, and exotic wood
• Compact, bushy structure ideal for SCROG or small spaces
• High resistance to mold and pests in challenging climates
• Stable genetics with uniform growth across phenotypes
• Ready in just 58–63 days—perfect for multiple outdoor harvests

Technical specifications

• Breeder / Brand: Silent Seeds
• Type: Feminized autoflowering
• Dominance: Indica-dominant hybrid (50% indica / 50% sativa)
• Genetics: Chemdawg Bx1 × MAC Auto
• Autos: 58–63 days from germination to harvest
• Indoor yield: 550–650 g/m² (1.8–2.2 oz/ft²)
• Outdoor yield: 100–400 g/plant (3.5–14 oz)
• Indoor height: Up to 1.40 m (4.59 ft)
• Outdoor height: Up to 1.40 m (4.59 ft)
• Difficulty: Medium (forgiving for beginners, rewarding for experts)
• Structure and vigour: Compact, bushy, short internodal spacing, high lateral branching
• Training: Suitable for LST and SCROG; avoid topping or FIM
• Recommended pot: 18–27 L (6.3–7.1 gal) final pot
• Light: 18–20 h daily throughout the cycle
• Temperature: 22–26 °C (71.6–78.8 °F) in veg; 20–25 °C (68–77 °F) in flower
• Humidity: 60–70% seedling; 50–60% veg; 40–50% flowering
• pH: 6.0–6.5 (soil); 5.8–6.2 (coco/hydro)
• Smell in grow: High – use a carbon filter like FloraKleen to control odor
• THC: 24–29%
• CBD: Less than 0.2%
• Aromatic profile: Limonene, myrcene, pinene, caryophyllene
• Flavour: Diesel, kush, pine, lemon, exotic wood, spices
• Effect: Deep physical relaxation, stress relief, evening use

How to grow MAC Dawg XXL Auto for maximum results

Quick overview: feminized autoflower · Silent Seeds · 58–63-day cycle · medium difficulty · ideal for indoor tents or outdoor gardens in temperate climates.

Safe start: Germinate seeds at 22–25 °C with high humidity. Transplant once the taproot is ~1 cm long. For faster rooting, Clon Fix strengthens early root development.

Stable seedling: Use a light, airy substrate. Water lightly and avoid overfeeding. Apply beneficial microbes like Mykos Root Paks to boost nutrient uptake and resilience.

Directed growth: Maintain 18–20 hours of light. Use LST to open the canopy and improve light penetration. Keep temperatures at 22–26 °C and RH at 50–60%.

Efficient flowering: Reduce RH to 40–50% to prevent mold. Support heavy colas with soft ties. Apply bloom boosters like Bloom Stimulator FloraMax Green Hope during peak flowering for denser buds.

Harvest and refinement: Harvest when trichomes are mostly milky with some amber. Flush 7–10 days before cutting. Dry at 18–22 °C and 50–60% RH, then cure for 2–4 weeks to enhance flavor and smoothness.

Frequently Asked Questions

How much yield can I expect from MAC Dawg XXL Auto?

Indoors, expect 550–650 g/m² (1.8–2.2 oz/ft²). Outdoors, plants can produce 100–400 g (3.5–14 oz), depending on conditions.

What size pot should I use?

Use a final pot of 18–27 L (6.3–7.1 gal) to avoid transplanting and support maximum growth.

Can I grow MAC Dawg XXL Auto outdoors in a cold climate?

Yes, its ruderalis heritage gives it good cold tolerance. Just ensure it gets plenty of sunlight and protect it from heavy rain to avoid mold.

Does it need a lot of nutrients?

It’s a heavy feeder but responds best to a balanced, progressive feeding schedule. Avoid over-fertilizing, especially in early stages.

Is it suitable for beginners?

Yes, its stability and resistance make it beginner-friendly, though it rewards experienced growers with top-tier results.

Personal Experience of Pevgrow’s CEO (Alan)

I grew MAC Dawg XXL Auto in my 120x120x200 cm tent with a 600W LED. From day one, it stood out—vigor you don’t usually see in autos. I used LST at week 2 to spread the canopy, and by flowering, it filled the space evenly. I fed it with a mineral base and added Bloom Stimulator FloraMax Green Hope at peak bloom. The smell was insane—diesel and lemon—so I ran a carbon filter. At day 61, I harvested 620 g of dense, frosty buds. The high is heavy and lasting, perfect for crashing after work. My pro tip? Don’t top it—just train gently with LST. This one’s a keeper.