[
  {
    "effect_size": null,
    "effect_unit": "",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "Short-day crops (poinsettia, chrysanthemum) flower when nights exceed a critical length (~11.75 h uninterrupted darkness for poinsettia). Long-day bedding plants (petunia, rudbeckia, dianthus, ageratum) flower earlier under night-interruption or day-extension lighting. Improper photoperiod misses the holiday or spring retail window; yield in this sector is saleable, scheduled pots, not biomass.",
    "study_count": null,
    "comparison_count": null,
    "source_url": "https://www.canr.msu.edu/news/new_bulletin_managing_photoperiod_in_the_greenhouse",
    "potential_yield_effect": null,
    "geography": "North American commercial floriculture greenhouses",
    "intervention": "Blackout cloth or low-intensity photoperiodic lighting",
    "comparator": "Natural daylength only",
    "dose": "",
    "dose_unit": "",
    "limitations": "Not a percent yield meta-analysis. Crop-specific critical photoperiods apply.",
    "source_year": 2013,
    "doi": "",
    "baseline": "",
    "factor_id": "ornamentals-photoperiod-scheduling",
    "crop_id": "ornamentals",
    "factor": "Photoperiod control (blackout or night-interruption lighting)",
    "factor_category": "Light",
    "direction": "positive",
    "effect_type": "other",
    "evidence_type": "review",
    "evidence_strength": "High",
    "prairie_relevance": "high",
    "source_title": "Managing Photoperiod in the Greenhouse (Runkle, MSU Extension; Lopez, Purdue Extension)",
    "notes": "This is a scheduling / market-timing factor. Missing Christmas poinsettia or Mother's Day bedding windows destroys crop value even if biomass is high. Alberta winter natural daylength already provides short days; summer production of short-day crops needs blackout."
  },
  {
    "effect_size": -15.0,
    "effect_unit": "% bract area (early drench)",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "'Freedom Red' poinsettia. Paclobutrazol drench 0.118 mg/container on dates from 1 Oct–2 Nov. Second-week-of-October drench cut bract area 15% (1997) and 12% (1998) versus untreated; anthesis date unchanged. Late October/early November drenches controlled late stretch with least bract penalty. Height and internode reductions were rapid and persistent.",
    "study_count": 2,
    "comparison_count": null,
    "source_url": "https://journals.ashs.org/horttech/view/journals/horttech/11/4/article-p557.xml",
    "potential_yield_effect": null,
    "geography": "US greenhouse poinsettia",
    "intervention": "Paclobutrazol substrate drench, timed",
    "comparator": "No PGR drench",
    "dose": "",
    "dose_unit": "",
    "limitations": "Poinsettia-specific rates. Other species (chrysanthemum, bedding plants) need labelled rates. Not a biomass yield increase.",
    "source_year": 2001,
    "doi": "",
    "baseline": "",
    "factor_id": "ornamentals-paclobutrazol-height",
    "crop_id": "ornamentals",
    "factor": "Paclobutrazol drench for height control (with bract-size trade-off)",
    "factor_category": "Crop management",
    "direction": "context_dependent",
    "effect_type": "other",
    "evidence_type": "greenhouse_trial",
    "evidence_strength": "High",
    "prairie_relevance": "high",
    "source_title": "Effects of paclobutrazol drench application date on poinsettia height and flowering (Faust, Korczynski & Klein 2001)",
    "notes": "Retail spec is compact, uniform pots. Height control raises pack-out and freight density. Early or high-dose applications tax bract size (the saleable 'flower')."
  },
  {
    "effect_size": null,
    "effect_unit": "",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "Ontario greenhouse chrysanthemums. Investigates major infestation routes of key thrips species. Thrips reduce saleable quality (scarring, virus) more than biomass. Biological control and exclusion are the commercial response.",
    "study_count": 1,
    "comparison_count": null,
    "source_url": "https://doi.org/10.3390/insects17020144",
    "potential_yield_effect": null,
    "geography": "Ontario commercial chrysanthemum greenhouses",
    "intervention": "None (route study)",
    "comparator": "Uninfested crop",
    "dose": "",
    "dose_unit": "",
    "limitations": "Does not report a pooled % yield loss.",
    "source_year": 2026,
    "doi": "10.3390/insects17020144",
    "baseline": "",
    "factor_id": "ornamentals-thrips-ontario-chrysanthemum",
    "crop_id": "ornamentals",
    "factor": "Thrips infestation routes in greenhouse chrysanthemum",
    "factor_category": "Pest management",
    "direction": "negative",
    "effect_type": "yield_loss",
    "evidence_type": "observational_study",
    "evidence_strength": "Moderate",
    "prairie_relevance": "high",
    "source_title": "Investigating Major Infestation Routes of Several Key Thrips Species in Greenhouse-Grown Chrysanthemums in Ontario, Canada (2026)",
    "notes": "Prairie-relevant pest pathway paper. Treat as a quality/pack-out constraint, not a percent yield meta-analysis."
  },
  {
    "effect_size": null,
    "effect_unit": "",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "2023 Alberta greenhouse survey. Bedding plants/ornamentals ranked among the higher gross-return crops per m² (after lettuce and tree seedlings). Industry is diversified; labour is the largest cost. Holiday and spring retail timing dominate revenue.",
    "study_count": 1,
    "comparison_count": null,
    "source_url": "https://open.alberta.ca/dataset/fbb2b0b5-53b9-4dbd-92b7-f37ec8ed9369/resource/f4313ce0-1ea0-45e0-bc34-18306b1d2128/download/agi-economics-production-marketing-greenhouse-crops-2023.pdf",
    "potential_yield_effect": null,
    "geography": "Alberta",
    "intervention": "Observed bedding plant / ornamental enterprise",
    "comparator": "Other Alberta greenhouse crops",
    "dose": "",
    "dose_unit": "",
    "limitations": "Survey, not a PGR or lighting trial.",
    "source_year": 2025,
    "doi": "",
    "baseline": "",
    "factor_id": "ornamentals-agriprofits-bedding",
    "crop_id": "ornamentals",
    "factor": "Alberta AgriProfit$ 2023 bedding plants / ornamentals returns",
    "factor_category": "Economics & Certification",
    "direction": "positive",
    "effect_type": "other",
    "evidence_type": "economic_benchmark",
    "evidence_strength": "High",
    "prairie_relevance": "high",
    "source_title": "Economics of Production and Marketing of Greenhouse Crops in Alberta 2023 (Laate)",
    "notes": "Profit in this enterprise is calendar and specification (height, branching, flower count), which is why photoperiod and PGRs are the primary 'yield' tools."
  },
  {
    "effect_size": -25.0,
    "effect_unit": "% time to market (chrysanthemum)",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "WUR greenhouse covering trials. Chrysanthemum time to market ~25% shorter under diffuse glass; anthurium ~40% shorter. Pot plants heavier. Tomato/cucumber biomass +5–11% in the same programme. Dueck noted sweet pepper and chrysanthemum were less tested than tomato/cucumber.",
    "study_count": null,
    "comparison_count": null,
    "source_url": "https://www.growsave.co.uk/diffuse-glass-for-greenhouses/",
    "potential_yield_effect": null,
    "geography": "Netherlands glasshouse floriculture",
    "intervention": "Diffuse glass roof",
    "comparator": "Clear glass",
    "dose": "",
    "dose_unit": "",
    "limitations": "Institutional summary of WUR trials, not a crop-specific meta-analysis. Confirm against the primary WUR reports before modelling.",
    "source_year": 2020,
    "doi": "",
    "baseline": "",
    "applicability": "near-direct",
    "evidence_tier": "E",
    "factor_id": "ornamentals-diffuse-glass-cycle",
    "crop_id": "ornamentals",
    "factor": "Diffuse glass shortening time-to-market (chrysanthemum)",
    "factor_category": "Climate",
    "direction": "positive",
    "effect_type": "other",
    "evidence_type": "review",
    "evidence_strength": "Moderate",
    "prairie_relevance": "moderate",
    "source_title": "Diffuse glass for greenhouses — WUR results summary (Growsave / Dueck, Hemming, Janse)",
    "notes": "Ornamental ‘yield’ here is faster, heavier, scheduled pots. A 25% shorter cycle raises pots/m²/year if the retail window can absorb them."
  },
  {
    "effect_size": null,
    "effect_unit": "",
    "ci_lower": null,
    "ci_upper": null,
    "conditions": "Optimizing supplemental light spectrum improved growth and yield of cut roses (Sci Rep 2023). Spectrum is not interchangeable with ‘more light’. Keep as a light-quality factor for floriculture, separate from photoperiod blackout.",
    "study_count": 1,
    "comparison_count": null,
    "source_url": "https://doi.org/10.1038/s41598-023-48266-3",
    "potential_yield_effect": null,
    "geography": "Greenhouse cut rose",
    "intervention": "Optimized supplemental LED spectrum",
    "comparator": "Non-optimized spectrum / control lighting",
    "dose": "",
    "dose_unit": "",
    "limitations": "Cut rose, not poinsettia or bedding impatiens. Extract tables before using a numeric %.",
    "source_year": 2023,
    "doi": "10.1038/s41598-023-48266-3",
    "baseline": "",
    "applicability": "mechanistic",
    "evidence_tier": "B",
    "factor_id": "ornamentals-dli-cut-rose",
    "crop_id": "ornamentals",
    "factor": "Supplemental light spectrum for cut-rose yield",
    "factor_category": "Light",
    "direction": "positive",
    "effect_type": "yield_gain",
    "evidence_type": "greenhouse_trial",
    "evidence_strength": "Moderate",
    "prairie_relevance": "low",
    "source_title": "Optimizing supplemental light spectrum improves growth and yield of cut roses (2023)",
    "notes": "Bedding-plant houses in Alberta are more often potted floriculture than cut rose. Applicability is mechanistic/near-direct for other ornamentals."
  }
]