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Premium Cannabis Genetics
For The Serious Grower

Sourced from elite Colorado breeders. 100% Germination Guarantee. Stealth Delivery.

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On all USA orders over $50. Discreet, plain-box packaging ensures your privacy is protected.

🧬 Elite Genetics

From F1 Hybrids to Landrace strains, we stock only the most stable and potent phenotypes.

🌱 Germination Guarantee

We stand by our seeds. If they don't pop, we replace them. Simple as that.

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Explore Our Seed Inventory

Whether you are setting up a Screen of Green (SCROG) or a massive outdoor crop, we have the strain for you.

BEST SELLER

Feminized Seeds

Photoperiod | 99.9% Female

Eliminate the guesswork. Our feminized cannabis seeds are bred to produce only female plants, ensuring every inch of your grow space is devoted to producing potent, resinous buds (Sinsemilla). Ideal for growers maximizing yield.

  • High THC & CBD options
  • Guaranteed bud production
  • Perfect for cloning
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FAST HARVEST

Autoflower Seeds

Ruderalis Hybrid | Fast Flowering

Integrating Cannabis ruderalis genetics, these plants flower automatically based on age, not light cycle. Perfect for perpetual harvests and discreet balcony grows. Go from seed to harvest in as little as 60 days.

  • No light schedule changes needed
  • Hardy and pest resistant
  • Compact stature
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NEW TECH

Triploid Seeds

Sterile | 3 Chromosome Sets

The future of commercial cultivation. Triploid genetics are naturally sterile, meaning they cannot be pollinated. This directs all plant energy into trichome and cannabinoid production, resulting in massive colas and higher ROI.

  • Seedless guarantee
  • 30-50% higher biomass
  • Shortened flowering time
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Regular Seeds

Male & Female | Breeding Stock

For the purists and breeders. Regular seeds produce both male and female plants, essential for creating your own F1 hybrids or preserving a mother plant. Experience the vigor of unaltered genetics.

  • Lowest price point
  • Create your own strains
  • Maximum genetic stability
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The Science of Cannabis Cultivation

At Colorado Seed Supply, we don't just sell seeds; we teach you how to master the art of the grow. Understanding the botany of Cannabis sativa L. is crucial for maximizing your harvest.

Phases of Growth

1. Germination: The process where the seed sprouts. Requires moisture, heat, and darkness. The taproot emerges, anchoring the plant.

2. Vegetative Stage: The plant focuses on structural growth (stems and fan leaves). Nitrogen is the key nutrient here. Light cycles usually run 18/6 (18 hours on, 6 off).

3. Flowering Stage: Triggered by a shift to 12/12 lighting (photoperiodism). The plant stops growing vertically and produces calyxes, pistils, and resin-filled trichomes.

Key Phytochemicals

  • Cannabinoids: Chemical compounds that interact with the human endocannabinoid system. Primary examples include Tetrahydrocannabinol (THC) and Cannabidiol (CBD).
  • Terpenes: Aromatic oils that flavor the buds and modulate effects (the Entourage Effect). Common terpenes include Myrcene (earthy, sedative), Limonene (citrus, energetic), and Pinene (pine, alert).

Nutrient Deficiency Quick Guide

Element Sign of Deficiency
Nitrogen (N) Lower leaves turn yellow (chlorosis).
Phosphorus (P) Slow growth, purple stems/leaves.
Potassium (K) Brown, burnt edges on leaves.
Calcium (Ca) Brown spots, weak stems.
Magnesium (Mg) Yellowing between leaf veins.
Tip: Always check your pH balance before adding nutrients. Soil should be 6.0-7.0 pH.

Top 5 High-Yield Strains for 2024

Looking for the biggest bang for your buck? These strains are renowned for their "g per watt" efficiency.

01

Blue Dream Auto (Sativa Dom)

A Colorado classic. Resistance to powdery mildew makes it perfect for beginners. Expect yields up to 600g/m² indoors. Flavor profile is heavy on blueberry and sweet vanilla.

02

Northern Lights Feminized (Indica)

The legendary indoor strain. Short, bushy, and incredibly resinous. Low odor profile makes it great for stealth grows. Hits hard with a relaxing body high.

03

Gorilla Glue #4 (GG4)

Known for gluing your scissors together during trim jail. Incredible THC levels often exceeding 28%. A heavy feeder that rewards you with dense, golf-ball sized nugs.

04

White Widow (Hybrid)

The coffee shop icon. Covered in white trichomes. High energy effect. Extremely resilient to temperature fluctuations.

05

Girl Scout Cookies (GSC)

Famous for its dessert-like aroma and purple hues. A lower yielder than Blue Dream, but the quality commands a premium price.

Potential Yield Calculator

Curious about your harvest? Use our estimator based on average strain performance and lighting wattage.

Seed Type Comparison

Feature Regular Seeds Feminized Seeds Autoflower Seeds
Gender 50% Male / 50% Female 99.9% Female 99.9% Female
Light Requirement Photoperiod (12/12 to flower) Photoperiod (12/12 to flower) Any (18/6 recommended)
Difficulty Advanced Intermediate Beginner
Cloning Excellent Good Poor
Yield Potential High Very High Medium

Frequently Asked Questions

Is it legal to buy cannabis seeds in the USA?

Yes. Under the 2018 Farm Bill, cannabis seeds are classified as hemp products as long as they contain less than 0.3% THC (which seeds do). They are legal to possess as novelty items or souvenirs.

How do I store my seeds?

Store your seeds in a cool, dark, and dry place. A refrigerator is ideal. Keep them in their original packaging or an airtight container to maintain viability for years.

What is the difference between Sativa and Indica?

Morphologically, Sativas are tall with thin leaves, originating from equatorial regions. Indicas are short, bushy, with broad leaves, originating from the Hindu Kush mountains. Hybrids are a mix of both.

Do you ship internationally?

Currently, Colorado Seed Supply ships to all 50 US states. International shipping is coming soon.