Granddaddy Purple (Cannabis Strain) — Strainpedia
Granddaddy Purple, commonly abbreviated as GDP, is one of the most visually iconic Indica-dominant Hybrid cultivars in modern cannabis history. Introduced in the early 2000s, GDP helped define the commercial purple era by combining deep anthocyanin coloration with dense resin production and grape-forward terpene expression. Its unmistakable violet buds, heavy body profile, and stable structure quickly established it as a cornerstone of West Coast Indica breeding and a permanent member of the Foundational Genetics tier.
Quick Facts
| Genetics | Purple Urkle × Big Bud |
|---|---|
| Breeder | Early 2000s California preservation |
| Variety | Indica-dominant Hybrid (~70% Indica) |
| Flowering Time | 8–9 weeks (56–63 days indoors) |
| Yield Potential | 450–600 g/m² (Medium–High) |
| Plant Height | 90–140 cm; compact, bushy structure |
| Climate Preference | Dry indoor environments or warm Mediterranean climates |
| Difficulty | Beginner–Intermediate (stable but humidity control recommended) |
Scientific & Botanical Overview
Granddaddy Purple is characterized by its deep violet pigmentation, driven by anthocyanin expression that intensifies under cooler nighttime temperatures. Buds are typically dense, rounded, and heavily coated in glandular trichomes, often appearing almost black-purple beneath silver frost.
Botanically, GDP expresses compact Indica morphology with tight internodal spacing and thick lateral branches supporting dense flower clusters. The influence of Big Bud contributes to yield stability, while Purple Urkle heritage delivers its distinctive coloration and terpene identity.
Effects & Use-Cases (Reported)
- Commonly reported effects: deep physical relaxation, calm mood shift, body heaviness.
- Use-case context: evening sessions, decompression, low-stimulation environments.
- Functional profile: gradual cerebral onset followed by pronounced physical grounding.
- Note: Observational reports only; not medical claims.
Aroma & Flavors
- Aroma: sweet grape, berry syrup, subtle earthy spice.
- Flavor: rich grape inhale with smooth herbal undertone.
- Signature finish: lingering berry sweetness with light earthiness.
- Terpene associations: myrcene, caryophyllene, pinene (phenotype-dependent).
Tested Cannabinoid & Terpene Ranges
| Compound | Typical Range* | Notes |
|---|---|---|
| Δ⁹-THC | ~17–24% | Moderate-to-high potency; body-forward expression common. |
| CBD | <1% | Typically trace levels. |
| Myrcene | Moderate–High | Associated with heavy relaxation and grape sweetness. |
| Caryophyllene | Moderate | Adds peppery depth. |
| Pinene | Low–Moderate | Contributes subtle freshness. |
| Terpene Profile | Grape / Berry / Earth | Defining purple Indica aromatic lane. |
*Ranges vary based on phenotype, cultivation practices, harvest timing, curing methods, and laboratory analysis.
Cultivation Notes
- Light Cycle: 18/6 vegetative; 12/12 flowering
- Stretch: Minimal to moderate during early flower
- Humidity Targets: 40–50% late flower to protect dense buds
- Color Enhancement: Cooler nighttime temperatures may intensify purple pigmentation
- Harvest Window: Late September to early October outdoors
Grower Notes (Week-by-Week Snapshot)
- Weeks 1–2: Compact structure establishes; minimal stretch.
- Weeks 3–4: Bud stacking intensifies; purple hues begin emerging.
- Weeks 5–6: Resin density increases; grape aroma becomes pronounced.
- Weeks 7–9: Full pigment expression; monitor trichome maturity.
- Post-Harvest: Slow cure enhances berry-forward terpene preservation.
Genetic Lineage
Granddaddy Purple combines Purple Urkle’s deep pigmentation and berry terpene lane with Big Bud’s yield-enhancing structure. This pairing produced a visually striking Indica-dominant hybrid that balanced aesthetic appeal with commercial reliability, helping popularize purple cultivars in mainstream markets.
Research Insights
GDP is frequently referenced in discussions of anthocyanin-driven pigmentation in cannabis. Its coloration provides a clear example of how environmental factors and genetic predisposition interact to produce vivid purple phenotypes. As one of the earliest widely distributed purple hybrids, it significantly influenced subsequent color-forward breeding programs.
Why Granddaddy Purple Is “Foundational Genetics”
Granddaddy Purple reshaped market demand by demonstrating that visual appeal—particularly deep violet coloration—could become a defining commercial trait. Its grape-forward terpene lane and stable Indica structure influenced a generation of purple-dominant hybrids, securing its position as a cornerstone of modern cannabis genetics.
Frequently Asked Questions
Why is Granddaddy Purple purple?
Its coloration is driven by anthocyanin pigments expressed genetically and intensified under cooler growing conditions.
Is GDP an Indica?
It is generally classified as Indica-dominant, though hybrid variation exists.
Does GDP taste like grapes?
Many reports describe a sweet grape and berry-forward flavor profile.
Is Granddaddy Purple strong?
It typically tests in the moderate-to-high THC range with a body-forward experience.
Educational Disclaimer: This page is provided for scientific and horticultural reference only and does not constitute medical or promotional advice. Cannabis cultivation, possession, and use are regulated by local laws. Always comply with applicable legislation in your region.
