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Granddaddy Purple No 17 Shop
The Official Cannabis collection · sheet 17No 17 · Granddaddy Purplevs Northern Lights

Comparison

Granddaddy Purple vs Northern Lights

Leafly users report the same top three effects for both, sleepy, relaxed and hungry; the difference is flavor and lineage. Northern Lights is an Afghani × Thai indica propagated in Holland after 1985 at what is now Sensi Seeds, and tastes of pine and earth rather than grape and berry.1,2 In state labs Northern Lights tests higher: 20.03% median THC against 17.87% for Granddaddy Purple.3

Side by side

Granddaddy PurpleNorthern Lights
TypeIndica (Leafly, Weedmaps); 70% indica per AllBud2,4,5Indica1
LineagePurple Urkle × Big Bud in most accounts; Mendo Purps × Skunk × Afghanistan per Leafly2,4,5Afghani × Thai1
Median THC (state lab tests)17.87% (512 tests)20.03% (406 tests)
Middle half of THC results15.00%–21.55%17.28%–22.05%
Top terpenes (median)Limonene, β-Caryophyllene, β-Myrcene (55 tests)β-Caryophyllene, Limonene, β-Myrcene (15 tests)
Leafly top effectsSleepy, relaxed, hungry2Sleepy, relaxed, hungry1
FlavorGrape, berry, violet2Pine, earthy, woody1
Flowering7–9 weeks (Leafly); about 65 days indoors (Weedmaps)2,445–50 days (Leafly)1

Lab rows come from the same state lab dataset and matching rules for both strains.3

Lab-tested THC: Granddaddy Purple vs Northern Lights

14% 16% 18% 20% 22% 24% Northern Lights Northern Lights: median 20.03%, middle half 17.28%–22.05%, 406 tests 20.0% n=406 Granddaddy Purple Granddaddy Purple: median 17.87%, middle half 15.00%–21.55%, 512 tests 17.9% n=512 Median total THC (dot) and middle half of tests (bar)
Median and middle half of total THC in state lab tests.3

A distant relative?

Possibly. Big Bud, one of Granddaddy Purple’s two parents in most accounts, is a three-way cross of Afghani, Northern Lights and Skunk #1, according to Leafly, and SeedFinder’s genealogy for Ken Estes’s own seed line traces Big Bud to a cross with Northern Lights #1.6,7 Northern Lights has its own guide in the Official Cannabis network at northernlightsstrain.com.

Which is easier to find

In Weedmaps snapshots from Oct 4, 2026 (Granddaddy Purple) and Oct 3, 2026 (Northern Lights), 56 stores within 50 miles of Los Angeles listed Granddaddy Purple flower on Weedmaps, against 98 stores for Northern Lights; around New York the counts were 58 and 97.8

More comparisons

Sources

  1. Leafly, Northern Lights strain information. Accessed Oct 4, 2026.
  2. Leafly, Granddaddy Purple (aka GDP) strain information. Accessed Oct 4, 2026.
  3. Cannlytics (CC BY 4.0), cannabis_results: public state lab results (filtered and aggregated by Official Cannabis). Accessed Oct 4, 2026.
  4. Weedmaps, Granddaddy Purple strain page. Accessed Oct 4, 2026.
  5. AllBud, Granddaddy Purple marijuana strain information and reviews. Accessed Oct 4, 2026.
  6. Leafly, Big Bud strain information. Accessed Oct 4, 2026.
  7. SeedFinder, Grand Daddy Purp (Grand Daddy Purp): strain info, cannabinoids and genealogy. Accessed Oct 4, 2026.
  8. Weedmaps listings, compiled by Official Cannabis, Weedmaps flower menu snapshot, 27 US markets, Oct 4, 2026. Accessed Oct 4, 2026. Latest capture Oct 4, 2026.