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The Official Cannabis collection · sheet 65No 65 · Watermelon Zvs Rainbow Runtz

Comparison

Watermelon Z vs Rainbow Runtz

Both carry Zkittlez: Leafly describes Rainbow Runtz as a double cross of Zkittlez and DoSiDos and, since 2024, also as Wizard Trees’ Runtz × RS11, Runtz itself being The Original Z × Gelato.1,2 Leafly users report similar effects, relaxed and sleepy, but different flavors: pear, rose and flowery for Rainbow Runtz, tropical fruit for Watermelon Z.1,3 Both lab samples are small: 21.73% median THC across 77 tests for Rainbow Runtz, against 18.60% across 63 for Watermelon Z.4

Side by side

Watermelon ZRainbow Runtz
TypeIndica-dominant hybrid per Leafly and Weedmaps; 70% indica per AllBud3,5,6Indica per Leafly; modern versions described as hybrid1
LineageThe Original Z × Watermelon per Leafly and Weedmaps; disputed3,5,7Zkittlez × DoSiDos (double cross); since 2024 also Runtz × RS11 (Wizard Trees)1
Median THC (state lab tests)18.60% (63 tests); small sample21.73% (77 tests); small sample
Middle half of THC results15.27%–22.59%17.89%–25.33%
Top terpenes (median)β-Caryophyllene, Limonene, Linalool (22 tests); 21 of them from NevadaToo few tests report individual terpenes (only 4)
Leafly’s top effectsSleepy, relaxed, giggly3Relaxed, sleepy, hungry1
FlavorTropical, tree fruit, sweet3Pear, rose, flowery1
Leafly THC listing24%325%1

Lab rows come from the same state lab dataset and matching rules for both strains.4

Lab-tested THC: Watermelon Z vs Rainbow Runtz

16% 20% 24% Rainbow Runtz Rainbow Runtz: median 21.73%, middle half 17.89%–25.33%, 77 tests 21.7% n=77 Watermelon Z Watermelon Z: median 18.60%, middle half 15.27%–22.59%, 63 tests 18.6% n=63 Median total THC (dot) and middle half of tests (bar)
Median and middle half of total THC in state lab tests. Small sample: Watermelon Z has only 63 tests; Rainbow Runtz has only 77 tests.4

The Z family

Runtz, Leafly’s Strain of the Year in 2020, is The Original Z × Gelato, and Watermelon Runtz, also called Melon Runtz, crosses Watermelon Zkittlez with Runtz; Leafly names Silent Seeds as its original breeder.2,8 Rainbow Runtz has its own guide in the Official Cannabis network at rainbowruntz.com.

Which is easier to find

On Oct 4, 2026, 104 stores within 50 miles of Los Angeles listed Watermelon Z flower on Weedmaps, against 95 stores for Rainbow Runtz; around New York the counts were 16 and 27.9 Most of the Watermelon Z items around Los Angeles were infused flower (95 of 111), which these counts include.9

More comparisons

Sources

  1. Leafly, Rainbow Runtz (aka Rainbow Runts) strain information. Accessed Oct 4, 2026.
  2. Leafly, The best-selling weed strains of 2025 (Morgan Rosendale) (2026-02-02). Accessed Oct 4, 2026.
  3. Leafly, Watermelon Z (aka Watermelon Zkittlez) strain information. Accessed Oct 4, 2026.
  4. Cannlytics (CC BY 4.0), cannabis_results: public state lab results (filtered and aggregated by Official Cannabis). Accessed Oct 4, 2026.
  5. Weedmaps, Watermelon Zkittlez (aka Wmz, Watermelon Skittles, Watermelon Z) strain page. Accessed Oct 4, 2026.
  6. AllBud, Watermelon Zkittlez marijuana strain information and reviews. Accessed Oct 4, 2026.
  7. SeedFinder, Watermelon Zkittlez (Dying Breed Seeds): strain info and breeder description. Accessed Oct 4, 2026.
  8. Leafly, Watermelon Runtz (aka Melon Runtz) strain information. Accessed Oct 4, 2026.
  9. 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.