Grandaddy Purple Feminised Seeds

Granddaddy Purple Feminised Seeds: The Grape-Coloured Classic That Made Purple Famous

If you’re looking to buy Granddaddy Purple feminised seeds in Australia, you’re not chasing a trend — you’re chasing the strain that defined purple. GDP is the original grape-and-berry icon: deep violet fades, chunky indica structure, and a candy-shop aroma that refuses to be ignored. She’s a 70/30 Indica-dominant legend from San Francisco, built for calm nights, pretty jars, and growers who want real colour without gimmicks.

Matty’s 3 Pillars for GDP (Save This)

• The Fade: Drop lights-off temps to <18°C from Week 7.
• The Food: Cut Nitrogen early — excess green masks purple.
• The pH: Hold 6.0–6.2 (soil) in the final 3 weeks to unlock violet.

Matty: “Nail these three and GDP does the rest.”

Quick Stats

Granddaddy Purple is a potent Indica-dominant hybrid (≈70/30) that typically tests around 17–23% THC. Indoors she finishes in 8–10 weeks. Outdoors in Australia, expect harvest from late March through April. The famous purple expression depends on three things only: cool nights, low Nitrogen late flower, and tight pH.

The Legend

Born in the early 2000s, GDP became a California staple because she was impossible to forget. The grape terps, the heavy indica posture, and the deep violet fades made her the strain people picture when someone says “purple weed.”

Her lineage — Mendo Purps × Skunk × Afghan — delivers a calm, grounding body effect without instantly switching your brain off.

Flavour & Aroma

On the nose: Loud grape and wild berries layered over earthy funk.

On the tongue: Sugary grape sweetness followed by floral earth and mild spice.

On the linger: Sweet hash and grape candy that sticks around.

Matty: “No tricks here — this is what purple is supposed to taste like.”

Effects — The GDP Stone Timeline

• 0–15 mins: The Grin. Mood lifts, shoulders drop, the world feels quieter.
• 15–60 mins: The Melt. Muscles unwind, stress slides off, thoughts slow down.
• 60+ mins: Pillow Talk. Calm, heavy, cosy — conversation optional.

Matty: “She’s not an instant knockout — but she will tuck you in if you let her.”

How I Grow It (Matty’s Way)

Skill level: Beginner–Intermediate. Compact, forgiving, but dense — airflow matters.

Training: Top early or FIM, then LST to create a wide, flat canopy. Even light = even colour.

Anthocyanin Unlock (Pro Tip): Purple pigments are pH-sensitive. In soil, anthocyanins express more vibrantly at 6.0–6.2. Drift toward 6.8+ and the purple dulls into grey-blue. Final three weeks? Stay low in the safe zone.

Nitrogen Timeline (This Matters):
Excess Nitrogen acts like a green “mask.” If the plant is still dark green in Week 7, the purple won’t show through.

• Week 3 flower: switch to a transition feed (≈50% less N).
• Week 6–7: leaves should be fading naturally.
• Week 7+: purple replaces green — that’s the handover.

Grow Log

Phase	Status	Matty’s Tip
Seedling	Early leaves, gentle growth	“Light hand, warm roots, no drowning.”
Veg Week 3	Compact bush, topped & trained	“Open her early — colour loves airflow.”
Flower Week 4	Buds stacking, no stretch	“Feed steady — she’s not a buffet.”
Flower Week 7	Purple hints appear	“Drop night temps now — this is the window.”
Final 14 Days	Rock-hard buds, full colour	“Drop RH to 35–40% — resin loves dry air.”

Advanced Notes (For the Nerds)

• Humidity Spike: Final 14 days at 35–40% RH increases resin density and prevents bud-core moisture.
• PPFD: 600–800 µmol/m²/s in bloom.
• EC: 1.6–1.8 peak flower. Over 2.0 = claw city.
• VPD: 1.2–1.5 kPa in flower.

Field Report — The VIC Rescue

“Met a grower in VIC pulling his hair out — freezing nights, still green GDP. Checked runoff: 7.2. We flushed with 5.8 water to reset the root zone to 6.2. Five days later, the leaf edges turned plum-purple. It wasn’t temperature — it was pH locking the pigments out.”

Final Verdict

Granddaddy Purple is the benchmark purple strain — not just for looks, but for a calm, satisfying grow and jars that turn heads. Finish her clean, stay disciplined with pH and Nitrogen, and she’ll reward you with deep violet colour and grape-candy terps that never go out of style.

Matty’s final word: “GDP’s not about forcing colour — it’s about getting out of her way at the right time.” 🍻

We Answer Your Questions (Q&A with Matty)