Harz_Kontrolleur The Objective
​I first came across Urban Seedlab during a rather controversial discussion on the German forum grower.ch. While the brand is polarizing, the genetic lineages raised a lot of questions about their actual performance. I decided to step in and run a rigorous performance evaluation to see if the results match the claims.
​To keep this review objective, I purchased the Lab File Box myself. For this run, I have prioritized Urbans 11 and Diamond Marker, as well as the exclusive bonus seeds included in the box: Permanent Chimera #35 x White Truffle. Additionally, through an Instagram connection, I received special test seeds: Gorillato x BBC and Lab Candy #37. My goal is a completely unbiased seed-to-harvest report.
​The "Elite 6" Selection Strategy
​I am starting this hunt with a perfect 100% germination rate (10/10) for these five primary strains. This means I have every single plant available for a direct head-to-head comparison. To ensure a consistent baseline, I am utilizing Greenhouse Bio Feeding.
​The goal is to select the single best phenotype of each strain, plus one additional "Wildcard" winner, to move a total of 6 plants into the final flowering stage. Evaluation criteria for this hunt include:
​Root vigor and colonization speed.
​Nodal structure and internodal spacing.
​Early terpene potential through systematic stem rubs (used as a tie-breaker when vigor is equal).
​Important Note on Stability:
This diary documents a specific phenotype selection (Pheno Hunt). Therefore, it focuses on the peak potential found within my selection rather than providing a definitive statement on the overall genetic stability of the seed lots.
​Substrate Setup (1L Phase)
​Base: BioBizz Light Mix enriched with 5% Earthworm Castings.
​Nutrition: A minimal baseline of 1g/L Greenhouse Bio Grow.
​Inoculation: Organic Nutrients Mycorrhiza were applied directly to the root surface and the planting hole during transplanting for immediate symbiotic contact.
​Kickstart: The first watering includes Greenhouse Enhancer to activate soil microbiology.
​Technical Baseline: Lighting & Environment
​Lighting: Currently running a Mars Hydro FC3000 EVO (supplemented with Adlite Blue) delivering a consistent 300–350 PPFD. This provides a high-energy start to maximize early structural development.
​Environmental Targets: Maintaining 24–26°C and 60–70% RH to ensure an optimal VPD for this high-light intensity.
​Initial Water Profile: pH 7.5 | EC 573 µS/cm | Calcium 81 mg/l | Magnesium 16.2 mg/l.
​My Adaptations for Week 1
​Mineral Balancing & Acclimatization: To correct the native 5:1 Ca:Mg ratio of my tap water, I have started a low-dose supplementation of 0.08 ml/L Mono-Magnesium (0.2 ml per 2.5L).
​The Strategy: While not strictly necessary at this exact moment, this early "metabolic priming" ensures the plants are perfectly acclimated to a stable 2.2:1 ratio before the nutrient demand spikes under the 350 PPFD intensity.
​Microbe Protection: All water is aged for 24 hours to allow Chlorine Dioxide to gas off, protecting the Mycorrhiza.
​pH Precision: Every irrigation is monitored with a Bluelab pH Pen, targeting a stable pH of 6.0–6.2.
