{
 "$schema": "https://orvik.app/api/v1/openapi.json",
 "id": "reference-tables",
 "title": "Orvik reference tables",
 "description": "The five published reference tables behind Orvik's field calculators: ISA tree growth factors, AAHA pet life-stage bands, mint metal content for 22 coins, the Mohs scale with its household scratch tools, and sowing timing for 34 crops. Each carries the body that publishes it and the caveat that makes it usable rather than merely quotable.",
 "url": "https://orvik.app/api/v1/reference-tables.json",
 "documentation": "https://orvik.app/api/",
 "generated": "2026-09-17",
 "publisher": {
  "name": "Orvik",
  "legal_name": "Vast Flow, LLP",
  "url": "https://orvik.app/",
  "documentation": "https://orvik.app/api/",
  "contact": "support@orvik.app",
  "compiled_by": {
   "name": "Merey Tleugazin",
   "url": "https://orvik.app/about/",
   "note": "Not a biologist, geologist or veterinarian. The compilation work, the sourcing and the method are his; the taxonomy and the published standards are cited to the bodies that set them."
  }
 },
 "licence": {
  "id": "CC-BY-4.0",
  "name": "Creative Commons Attribution 4.0 International",
  "url": "https://creativecommons.org/licenses/by/4.0/",
  "attribution": "Orvik (https://orvik.app)",
  "covers": "The compilation: the key structure, the entry list, the trait coding, the joins and every derived column. Use it commercially, modify it, redistribute it; credit Orvik with a link."
 },
 "upstream_sources": [],
 "scope_limits": {
  "no_identification": "No endpoint identifies a specimen. The keys narrow possibilities from traits a reader has observed; they never return a determination, and a filtered list is not an answer.",
  "no_safety_clearance": "Nothing here certifies that anything is safe to eat, touch or handle. The toxicity, mushroom, wild berry, snake and caterpillar keys flag risk and name the poison centre; they do not clear anything.",
  "no_prices": "No market prices, appraisals or valuations. The coin endpoint publishes metal content only, and the spot price is supplied by the caller."
 },
 "not_published": [
  {
   "what": "The competitor app snapshot behind /compare/ and /alternatives/.",
   "why": "The metadata and in-app purchase lists come from the Apple App Store and are Apple's to license, not ours. The positioning is each publisher's own marketing. Republishing either keyless and CC BY would relicense content we do not own and distribute our competitors' copy at our own cost.",
   "instead": "https://orvik.app/compare/"
  },
  {
   "what": "Individual occurrence records — coordinates, dates, observer, photographs.",
   "why": "Orvik holds only aggregate counts and month histograms. The records themselves are the upstream databases' to distribute, and they already do so properly.",
   "instead": "https://www.gbif.org/occurrence/search"
  },
  {
   "what": "Any identification made by the Orvik app, and any user photograph.",
   "why": "None is retained in a form that could be published, and publishing it is not something a user agreed to.",
   "instead": "https://orvik.app/privacy/"
  }
 ],
 "count": 5,
 "engine_source": "https://orvik.app/js/engine.js",
 "engine_note": "Every figure here is imported from the same ES module the browser calculators and the MCP tools run on, so this endpoint cannot state a value the page does not compute with.",
 "row_counts": {
  "tree_growth_factors": 32,
  "pet_ageing": 5,
  "coin_metal_content": 22,
  "mohs_scale": 10,
  "seed_starting": 34
 },
 "data": {
  "tree_growth_factors": {
   "title": "Tree growth factors (ISA)",
   "authority": "International Society of Arboriculture",
   "page": "https://orvik.app/tools/tree-age-calculator/",
   "method": "age = (circumference / pi / 2.54) x growth factor x site adjustment",
   "units": "growth factor is years per inch of trunk DIAMETER, measured at 1.37 m / 4 ft 6 in (DBH)",
   "error_band": 0.25,
   "error_note": "Treat the result as +/-25% on a typical open-grown tree, and worse on a suppressed forest tree, an irrigated street tree, or any tree whose species was guessed. Getting the species wrong is the largest error available: pin oak and white oak differ by 67% and look similar to a beginner. The method fails outright on multi-stemmed, buttressed or fluted trunks, on palms, which have no growth rings, and on clonal species such as aspen.",
   "site_adjustments": [
    {
     "id": "open",
     "factor": 1,
     "label": "Open grown — lawn, park, field edge"
    },
    {
     "id": "forest",
     "factor": 1.6,
     "label": "Forest interior — grew up under a canopy"
    },
    {
     "id": "street",
     "factor": 0.75,
     "label": "Irrigated and fertilised street or garden tree"
    }
   ],
   "rows": [
    {
     "species": "Aspen",
     "growth_factor": 2,
     "years_at_30cm_diameter": 24,
     "note": "Fast and short-lived"
    },
    {
     "species": "Cottonwood",
     "growth_factor": 2,
     "years_at_30cm_diameter": 24,
     "note": "The fastest common hardwood"
    },
    {
     "species": "Silver maple",
     "growth_factor": 3,
     "years_at_30cm_diameter": 35,
     "note": "Fast, weak-wooded"
    },
    {
     "species": "Basswood / linden",
     "growth_factor": 3,
     "years_at_30cm_diameter": 35,
     "note": null
    },
    {
     "species": "Tulip tree",
     "growth_factor": 3,
     "years_at_30cm_diameter": 35,
     "note": null
    },
    {
     "species": "Pin oak",
     "growth_factor": 3,
     "years_at_30cm_diameter": 35,
     "note": "Much faster than other oaks"
    },
    {
     "species": "River birch",
     "growth_factor": 3.5,
     "years_at_30cm_diameter": 41,
     "note": null
    },
    {
     "species": "Scots pine",
     "growth_factor": 3.5,
     "years_at_30cm_diameter": 41,
     "note": null
    },
    {
     "species": "American elm",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "American sycamore",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "Green ash",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "Honey locust",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "Northern red oak",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "Sweetgum",
     "growth_factor": 4,
     "years_at_30cm_diameter": 47,
     "note": null
    },
    {
     "species": "Red maple",
     "growth_factor": 4.5,
     "years_at_30cm_diameter": 53,
     "note": null
    },
    {
     "species": "Norway maple",
     "growth_factor": 4.5,
     "years_at_30cm_diameter": 53,
     "note": null
    },
    {
     "species": "Black walnut",
     "growth_factor": 4.5,
     "years_at_30cm_diameter": 53,
     "note": null
    },
    {
     "species": "Austrian pine",
     "growth_factor": 4.5,
     "years_at_30cm_diameter": 53,
     "note": null
    },
    {
     "species": "Colorado blue spruce",
     "growth_factor": 4.5,
     "years_at_30cm_diameter": 53,
     "note": null
    },
    {
     "species": "White oak",
     "growth_factor": 5,
     "years_at_30cm_diameter": 59,
     "note": null
    },
    {
     "species": "Eastern white pine",
     "growth_factor": 5,
     "years_at_30cm_diameter": 59,
     "note": null
    },
    {
     "species": "Douglas fir",
     "growth_factor": 5,
     "years_at_30cm_diameter": 59,
     "note": null
    },
    {
     "species": "Black cherry",
     "growth_factor": 5,
     "years_at_30cm_diameter": 59,
     "note": null
    },
    {
     "species": "Paper birch",
     "growth_factor": 5,
     "years_at_30cm_diameter": 59,
     "note": null
    },
    {
     "species": "Sugar maple",
     "growth_factor": 5.5,
     "years_at_30cm_diameter": 65,
     "note": null
    },
    {
     "species": "White ash",
     "growth_factor": 5.5,
     "years_at_30cm_diameter": 65,
     "note": null
    },
    {
     "species": "Red pine",
     "growth_factor": 5.5,
     "years_at_30cm_diameter": 65,
     "note": null
    },
    {
     "species": "Flowering dogwood",
     "growth_factor": 7,
     "years_at_30cm_diameter": 83,
     "note": "Slow understory tree"
    },
    {
     "species": "Redbud",
     "growth_factor": 7,
     "years_at_30cm_diameter": 83,
     "note": "Slow understory tree"
    },
    {
     "species": "Ironwood / hornbeam",
     "growth_factor": 7,
     "years_at_30cm_diameter": 83,
     "note": "Very slow"
    },
    {
     "species": "Shagbark hickory",
     "growth_factor": 7.5,
     "years_at_30cm_diameter": 89,
     "note": "Very slow"
    },
    {
     "species": "Horse chestnut",
     "growth_factor": 8,
     "years_at_30cm_diameter": 94,
     "note": "The slowest on this table"
    }
   ]
  },
  "pet_ageing": {
   "title": "Canine and feline life-stage ageing",
   "authority": "American Animal Hospital Association / AVMA life stage guidelines",
   "page": "https://orvik.app/tools/pet-age-calculator/",
   "method": "Three phases, not a multiplier: year one is worth y1 human years, year two brings the total to y2, and every year after adds `per`, which is scaled by adult size.",
   "why_not_seven": "The seven-year rule has no scientific origin and fails twice: a one-year-old dog is sexually mature with a full adult skeleton, and a Great Dane at eight is geriatric while a chihuahua at eight is middle-aged.",
   "epigenetic_alternative": {
    "formula": "human_years = 16 * ln(dog_years) + 31",
    "source": "Wang et al. 2020, Cell Systems — DNA methylation clock",
    "url": "https://www.cell.com/cell-systems/fulltext/S2405-4712(20)30203-9",
    "caveat": "Labrador retrievers only, so it cannot express the size effect that dominates the second half of a dog's life. Shown alongside the life-stage figure, never instead of it."
   },
   "dog_bands": [
    {
     "id": "toy",
     "label": "Toy — under 9 kg / 20 lb",
     "y1": 15,
     "y2": 24,
     "per": 4,
     "senior": 10,
     "lifespan": "14–16 years"
    },
    {
     "id": "small",
     "label": "Small — 9–11 kg / 20–25 lb",
     "y1": 15,
     "y2": 24,
     "per": 4.5,
     "senior": 10,
     "lifespan": "13–15 years"
    },
    {
     "id": "medium",
     "label": "Medium — 11–23 kg / 25–50 lb",
     "y1": 15,
     "y2": 24,
     "per": 5,
     "senior": 9,
     "lifespan": "11–13 years"
    },
    {
     "id": "large",
     "label": "Large — 23–45 kg / 50–100 lb",
     "y1": 14,
     "y2": 22,
     "per": 6,
     "senior": 7,
     "lifespan": "10–12 years"
    },
    {
     "id": "giant",
     "label": "Giant — over 45 kg / 100 lb",
     "y1": 12,
     "y2": 20,
     "per": 7.5,
     "senior": 6,
     "lifespan": "7–9 years"
    }
   ],
   "cat": {
    "id": "cat",
    "label": "Cat",
    "y1": 15,
    "y2": 24,
    "per": 4,
    "senior": 11,
    "lifespan": "12–18 years"
   }
  },
  "coin_metal_content": {
   "title": "Actual silver and gold weight of common coins",
   "authority": "Published mint specifications",
   "page": "https://orvik.app/tools/coin-melt-value-calculator/",
   "units": "troy ounces of fine metal per coin",
   "method": "melt value = troy ounces x spot price, which the caller supplies. Orvik publishes no prices.",
   "typical_dealer_fraction": 0.88,
   "dealer_fraction_note": "Illustrative only. Nobody pays spot; the gap is the dealer's margin, a few percent on recognised bullion and wider on scrap. This is not a quote and is not sourced from a dealer.",
   "caveat": "Melt value is a FLOOR, not a price. Numismatic premium, dealer spread and bullion premium all sit on top of it and any can dominate: a 1916-D Mercury dime holds about $2 of silver and sells for thousands. Melting a scarce date destroys that value permanently.",
   "rows": [
    {
     "id": "us-dime-roosevelt",
     "group": "United States silver",
     "name": "Dime, 1946–1964 (Roosevelt)",
     "metal": "silver",
     "troy_oz": 0.0723,
     "years": "1946–1964"
    },
    {
     "id": "us-dime-mercury",
     "group": "United States silver",
     "name": "Dime, Mercury 1916–1945",
     "metal": "silver",
     "troy_oz": 0.0723,
     "years": "1916–1945"
    },
    {
     "id": "us-quarter",
     "group": "United States silver",
     "name": "Quarter, 1932–1964 (Washington)",
     "metal": "silver",
     "troy_oz": 0.1808,
     "years": "1932–1964"
    },
    {
     "id": "us-half-90",
     "group": "United States silver",
     "name": "Half dollar, 1964 (Kennedy, 90%)",
     "metal": "silver",
     "troy_oz": 0.3617,
     "years": "1964"
    },
    {
     "id": "us-half-40",
     "group": "United States silver",
     "name": "Half dollar, 1965–1970 (Kennedy, 40%)",
     "metal": "silver",
     "troy_oz": 0.1479,
     "years": "1965–1970"
    },
    {
     "id": "us-dollar-morgan-peace",
     "group": "United States silver",
     "name": "Morgan or Peace dollar",
     "metal": "silver",
     "troy_oz": 0.7734,
     "years": "1878–1935"
    },
    {
     "id": "us-ike-40",
     "group": "United States silver",
     "name": "Eisenhower dollar, 40% silver",
     "metal": "silver",
     "troy_oz": 0.3161,
     "years": "1971–1976"
    },
    {
     "id": "us-war-nickel",
     "group": "United States silver",
     "name": "War nickel, 35% silver",
     "metal": "silver",
     "troy_oz": 0.0563,
     "years": "1942–1945"
    },
    {
     "id": "us-silver-eagle",
     "group": "United States silver",
     "name": "American Silver Eagle, 1 oz",
     "metal": "silver",
     "troy_oz": 1,
     "years": "1986–"
    },
    {
     "id": "uk-shilling-sterling",
     "group": "United Kingdom silver",
     "name": "Pre-1920 sterling shilling",
     "metal": "silver",
     "troy_oz": 0.1682,
     "years": "to 1919"
    },
    {
     "id": "uk-shilling-half",
     "group": "United Kingdom silver",
     "name": "1920–1946 half-silver shilling",
     "metal": "silver",
     "troy_oz": 0.0841,
     "years": "1920–1946"
    },
    {
     "id": "uk-halfcrown",
     "group": "United Kingdom silver",
     "name": "Pre-1920 sterling half crown",
     "metal": "silver",
     "troy_oz": 0.4205,
     "years": "to 1919"
    },
    {
     "id": "uk-florin",
     "group": "United Kingdom silver",
     "name": "Pre-1920 sterling florin",
     "metal": "silver",
     "troy_oz": 0.3364,
     "years": "to 1919"
    },
    {
     "id": "ca-dime-80",
     "group": "Canada silver",
     "name": "Dime, 80% silver",
     "metal": "silver",
     "troy_oz": 0.06,
     "years": "1920–1966"
    },
    {
     "id": "ca-quarter-80",
     "group": "Canada silver",
     "name": "Quarter, 80% silver",
     "metal": "silver",
     "troy_oz": 0.15,
     "years": "1920–1966"
    },
    {
     "id": "ca-maple-ag",
     "group": "Canada silver",
     "name": "Silver Maple Leaf, 1 oz",
     "metal": "silver",
     "troy_oz": 1,
     "years": "1988–"
    },
    {
     "id": "us-gold-eagle",
     "group": "Gold",
     "name": "American Gold Eagle, 1 oz",
     "metal": "gold",
     "troy_oz": 1,
     "years": "1986–"
    },
    {
     "id": "za-krugerrand",
     "group": "Gold",
     "name": "Krugerrand, 1 oz",
     "metal": "gold",
     "troy_oz": 1,
     "years": "1967–"
    },
    {
     "id": "ca-maple-au",
     "group": "Gold",
     "name": "Canadian Gold Maple Leaf, 1 oz",
     "metal": "gold",
     "troy_oz": 1,
     "years": "1979–"
    },
    {
     "id": "uk-sovereign",
     "group": "Gold",
     "name": "British gold sovereign",
     "metal": "gold",
     "troy_oz": 0.2354,
     "years": "1817–"
    },
    {
     "id": "us-double-eagle",
     "group": "Gold",
     "name": "US $20 Double Eagle (Saint-Gaudens / Liberty)",
     "metal": "gold",
     "troy_oz": 0.9675,
     "years": "1850–1933"
    },
    {
     "id": "us-eagle-10",
     "group": "Gold",
     "name": "US $10 Eagle",
     "metal": "gold",
     "troy_oz": 0.48375,
     "years": "1838–1933"
    }
   ]
  },
  "mohs_scale": {
   "title": "Mohs hardness scale with field scratch tools",
   "authority": "Friedrich Mohs, 1812; absolute values from indentation hardness measurement",
   "page": "https://orvik.app/tools/mohs-hardness-scale/",
   "measures": "Scratch resistance — NOT toughness, strength or durability.",
   "ordinal_warning": "The scale is ordinal, not proportional, and the intervals were never meant to be equal. Corundum at 9 is roughly four times as hard as topaz at 8, and diamond at 10 roughly four times corundum again: the gap between 9 and 10 exceeds the gap between 1 and 9.",
   "absolute_reference": "quartz = 100",
   "tool_window": 0.6,
   "field_test_warning": "A grey line that wipes off with a thumb is metal deposited on the mineral, which means the mineral is HARDER than the steel — the opposite of what it looks like. Cleavage can peel a sheet away and read as a soft scratch. Hardness can be directional: kyanite is about 4.5 along its blades and about 7 across them.",
   "rows": [
    {
     "hardness": 1,
     "mineral": "Talc",
     "absolute_hardness": 1,
     "field_note": "Crumbles under a fingernail; feels soapy"
    },
    {
     "hardness": 2,
     "mineral": "Gypsum",
     "absolute_hardness": 2,
     "field_note": "A fingernail (2.5) scratches it"
    },
    {
     "hardness": 3,
     "mineral": "Calcite",
     "absolute_hardness": 9,
     "field_note": "A copper coin (3.5) scratches it"
    },
    {
     "hardness": 4,
     "mineral": "Fluorite",
     "absolute_hardness": 21,
     "field_note": "A knife scratches it easily"
    },
    {
     "hardness": 5,
     "mineral": "Apatite",
     "absolute_hardness": 48,
     "field_note": "A knife scratches it with effort"
    },
    {
     "hardness": 6,
     "mineral": "Orthoclase feldspar",
     "absolute_hardness": 72,
     "field_note": "Scratches glass; a steel file (6.5) scratches it"
    },
    {
     "hardness": 7,
     "mineral": "Quartz",
     "absolute_hardness": 100,
     "field_note": "Scratches glass and steel easily"
    },
    {
     "hardness": 8,
     "mineral": "Topaz",
     "absolute_hardness": 200,
     "field_note": "Scratches quartz"
    },
    {
     "hardness": 9,
     "mineral": "Corundum — ruby and sapphire",
     "absolute_hardness": 400,
     "field_note": "Scratches topaz"
    },
    {
     "hardness": 10,
     "mineral": "Diamond",
     "absolute_hardness": 1600,
     "field_note": "Scratches everything"
    }
   ],
   "household_tools": [
    {
     "hardness": 2.5,
     "object": "Fingernail"
    },
    {
     "hardness": 3.5,
     "object": "Copper coin"
    },
    {
     "hardness": 4.5,
     "object": "Iron nail"
    },
    {
     "hardness": 5.5,
     "object": "Window glass"
    },
    {
     "hardness": 5.5,
     "object": "Pocket knife blade"
    },
    {
     "hardness": 6.5,
     "object": "Steel file"
    },
    {
     "hardness": 7,
     "object": "Quartz pebble"
    },
    {
     "hardness": 8.5,
     "object": "Masonry drill bit (tungsten carbide)"
    }
   ]
  },
  "seed_starting": {
   "title": "Indoor sowing and transplant timing for 34 crops",
   "authority": "Standard extension-service guidance",
   "page": "https://orvik.app/tools/seed-starting-calculator/",
   "method": "Every seed-packet instruction is written relative to one number: the average last spring frost date. indoor_weeks_before_frost is weeks BEFORE that date to sow under cover; plant_out_weeks_from_frost is weeks relative to it, negative meaning before.",
   "zone_caveat": "A USDA hardiness zone is a winter-MINIMUM band, not a frost date. The zone table is a starting point for somebody who does not know their own date; the real number is local and worth looking up.",
   "rows": [
    {
     "crop": "Tomato",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 2,
     "note": "Set out only once nights stay above 10 °C"
    },
    {
     "crop": "Pepper and chilli",
     "indoor_weeks_before_frost": 8,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 2,
     "note": "Needs 25 °C soil to germinate"
    },
    {
     "crop": "Aubergine / eggplant",
     "indoor_weeks_before_frost": 8,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 2,
     "note": "The most heat-demanding of the three"
    },
    {
     "crop": "Tomatillo",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 1,
     "note": "Plant two — it will not set fruit alone"
    },
    {
     "crop": "Basil",
     "indoor_weeks_before_frost": 5,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 2,
     "note": "Cold below 10 °C blackens the leaves"
    },
    {
     "crop": "Broccoli",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -3,
     "note": "Transplants tolerate light frost"
    },
    {
     "crop": "Cabbage",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -3,
     "note": null
    },
    {
     "crop": "Cauliflower",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -2,
     "note": "Any check to growth causes buttoning"
    },
    {
     "crop": "Brussels sprouts",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -2,
     "note": "Long season — sow for an autumn harvest"
    },
    {
     "crop": "Kale",
     "indoor_weeks_before_frost": 5,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -3,
     "note": "Sweeter after frost"
    },
    {
     "crop": "Lettuce",
     "indoor_weeks_before_frost": 4,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -3,
     "note": "Bolts once nights stay warm"
    },
    {
     "crop": "Celery",
     "indoor_weeks_before_frost": 10,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -1,
     "note": "Very slow to germinate"
    },
    {
     "crop": "Onion from seed",
     "indoor_weeks_before_frost": 10,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -4,
     "note": "Match the day-length type to your latitude"
    },
    {
     "crop": "Leek",
     "indoor_weeks_before_frost": 10,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -3,
     "note": null
    },
    {
     "crop": "Cucumber",
     "indoor_weeks_before_frost": 3,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 1,
     "note": "Dislikes root disturbance — use pots"
    },
    {
     "crop": "Squash and courgette",
     "indoor_weeks_before_frost": 3,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 1,
     "note": "Grows so fast that direct sowing often catches up"
    },
    {
     "crop": "Pumpkin",
     "indoor_weeks_before_frost": 3,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 1,
     "note": null
    },
    {
     "crop": "Melon",
     "indoor_weeks_before_frost": 3,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 2,
     "note": "Needs warm soil and a long season"
    },
    {
     "crop": "Sweetcorn",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": 1,
     "note": "Direct sow; plant in a block, not a row"
    },
    {
     "crop": "Bean, bush and pole",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": 1,
     "note": "Rots in cold wet soil"
    },
    {
     "crop": "Pea",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -5,
     "note": "Sow as soon as the soil can be worked"
    },
    {
     "crop": "Carrot",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -3,
     "note": "Never transplants well"
    },
    {
     "crop": "Beetroot",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -3,
     "note": null
    },
    {
     "crop": "Radish",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -4,
     "note": "Ready in about four weeks"
    },
    {
     "crop": "Spinach",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -5,
     "note": "Bolts in heat"
    },
    {
     "crop": "Turnip",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -4,
     "note": null
    },
    {
     "crop": "Parsnip",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -3,
     "note": "Slow and erratic; use fresh seed"
    },
    {
     "crop": "Potato",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": -2,
     "note": "Plant chitted seed potatoes"
    },
    {
     "crop": "Garlic",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": 26,
     "note": "Plant in autumn, about six months after last frost"
    },
    {
     "crop": "Sunflower",
     "indoor_weeks_before_frost": null,
     "direct_sow_only": true,
     "plant_out_weeks_from_frost": 0,
     "note": null
    },
    {
     "crop": "Zinnia",
     "indoor_weeks_before_frost": 4,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 1,
     "note": null
    },
    {
     "crop": "Marigold",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 0,
     "note": null
    },
    {
     "crop": "Cosmos",
     "indoor_weeks_before_frost": 4,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": 0,
     "note": "Direct sowing works just as well"
    },
    {
     "crop": "Sweet pea",
     "indoor_weeks_before_frost": 6,
     "direct_sow_only": false,
     "plant_out_weeks_from_frost": -4,
     "note": "Autumn sowing gives the strongest plants"
    }
   ],
   "zone_frost_dates": [
    {
     "usda_zone": "3",
     "typical_last_frost": "05-25"
    },
    {
     "usda_zone": "4",
     "typical_last_frost": "05-15"
    },
    {
     "usda_zone": "5",
     "typical_last_frost": "05-01"
    },
    {
     "usda_zone": "6",
     "typical_last_frost": "04-15"
    },
    {
     "usda_zone": "7",
     "typical_last_frost": "04-01"
    },
    {
     "usda_zone": "8",
     "typical_last_frost": "03-15"
    },
    {
     "usda_zone": "9",
     "typical_last_frost": "02-15"
    },
    {
     "usda_zone": "10",
     "typical_last_frost": "01-31"
    }
   ]
  }
 }
}