# Garden Calculators

Garden math for agents: growing degree days, plant spacing, bed soil, drip irrigation, fertilizer, compost balance, frost risk and planting dates.

## How to pay

Machine-payable over x402. USDC on: Base (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp), Polygon (eip155:137), Arbitrum One (eip155:42161).
No accounts. No API keys. No signup. The paying wallet is the account.

## Machine-readable

- OpenAPI: https://garden-calc.x402tookit.com/openapi.json
- x402 manifest: https://garden-calc.x402tookit.com/.well-known/x402
- Catalog (free): https://garden-calc.x402tookit.com/catalog
- Health (free): https://garden-calc.x402tookit.com/health
- Uptime (free): https://garden-calc.x402tookit.com/uptime

## Endpoints (8)

### GET /compost-cn-ratio — $0.02
Carbon-to-nitrogen ratio of a compost mix by the Cornell formula, or the greens-to-browns amounts that reach a target ratio.
Params: ingredients?: string, green?: string, brown?: string, greenCn?: number, brownCn?: number, targetCn?: number
Example: https://garden-calc.x402tookit.com/compost-cn-ratio?ingredients=grass+clippings%3A10%3A80%3B+leaves%3A6%3A30

### GET /drip-irrigation — $0.02
Drip irrigation math: gallons for inches of water over an area, emitter flow, supply limit and run time per watering.
Params: areaSqFt: number, inchesPerWeek: number, emitterCount: integer, emitterGph: number, wateringsPerWeek?: integer, supplyGpm?: number, efficiencyPercent?: number
Example: https://garden-calc.x402tookit.com/drip-irrigation?areaSqFt=100&inchesPerWeek=1&emitterCount=25&emitterGph=1&wateringsPerWeek=3&supplyGpm=5

### GET /fertilizer-rate — $0.02
Fertilizer product needed for a nutrient target per 1000 sq ft from its N-P-K analysis, with the P and K delivered and bags.
Params: analysis: string, areaSqFt: number, targetLbPer1000SqFt: number, nutrient?: string, bagLb?: number
Example: https://garden-calc.x402tookit.com/fertilizer-rate?analysis=10-10-10&areaSqFt=2500&targetLbPer1000SqFt=1&nutrient=n&bagLb=50

### GET /frost-risk — $0.02
Frost or freeze class of a forecast low against plant hardiness, plus where a date sits against your average frost dates.
Params: lowTemp: number, unit?: string, hardiness?: string, date?: string, averageLastFrost?: string, averageFirstFrost?: string
Example: https://garden-calc.x402tookit.com/frost-risk?lowTemp=31&unit=f&hardiness=tender&date=2026-04-20&averageLastFrost=2026-05-01

### GET /growing-degree-days — $0.02
Growing degree days from daily lows and highs with a base temperature and upper cutoff: daily and cumulative totals.
Params: days: string, unit?: string, crop?: string, baseTemp?: number, upperTemp?: number, targetGdd?: number
Example: https://garden-calc.x402tookit.com/growing-degree-days?days=48%3A72%3B+52%3A80%3B+55%3A88%3B+40%3A70&unit=f&crop=corn

### GET /plant-spacing — $0.02
Plants that fit a bed at a spacing (grid or offset rows) and seeds to sow from germination rate, per bed and per square foot.
Params: lengthFt?: number, widthFt?: number, areaSqFt?: number, spacingIn: number, rowSpacingIn?: number, layout?: string, germinationPercent?: number, seedsPerHole?: integer
Example: https://garden-calc.x402tookit.com/plant-spacing?lengthFt=8&widthFt=4&spacingIn=6&germinationPercent=80

### GET /planting-dates — $0.02
Planting calendar from your frost date: dates for tasks given as weeks before or after, such as seeds indoors 6 weeks before.
Params: frostDate: string, tasks: string
Example: https://garden-calc.x402tookit.com/planting-dates?frostDate=2027-05-01&tasks=tomato+seeds+indoors%3A-6%3B+lettuce+seeds+outdoors%3A-4%3B+tomato+transplant%3A2%3B+bean+seeds%3A1

### GET /soil-volume — $0.02
Soil or mulch for a rectangular or round bed: cubic feet, yards, litres, bags, settling allowance and a mix split by parts.
Params: shape: string, lengthOrDiameter: number, width?: number, depth: number, unit?: string, settlingPercent?: number, bagCuFt?: number, mix?: string
Example: https://garden-calc.x402tookit.com/soil-volume?shape=rectangle&lengthOrDiameter=8&width=4&depth=1&unit=ft&settlingPercent=10&mix=topsoil%3A5%3B+compost%3A3%3B+perlite%3A2

## Terms

Garden calculators using standard formulas, published conventions (Cornell composting, NWS frost wording) and your inputs, provided as is. Plant response depends on variety, microclimate, soil and weather; frost thresholds and planting offsets are common guidance, not guarantees. Fertilizer and water amounts are starting points: follow product labels and local extension advice.