Frost Date Calculator
First & last frost dates for your hardiness zone.
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Planning & Yield — 20 calculators
Popular Garden Yield Estimator
Predict your harvest from your planting plan.
Use ToolNew Feed a Family Planner
Work backwards from your household to the rows and bed size each crop needs.
Use ToolNew Greenhouse Sizing Calculator
Size a greenhouse or high tunnel: grow area, heating load and the ventilation CFM the glazing demands.
Use ToolNew Garden Area Calculator
Square footage of a rectangle, triangle, circle or oval bed, plus the soil, mulch and plant counts that follow.
Use ToolNew Plant Population Calculator
Plants per acre and per square foot from row spacing and in-row spacing, scaled to your plot with a seed-order estimate.
Use ToolNew Growing Degree Days Calculator
Daily and season GDD accumulation from high and low temperature, with corn-style caps and a progress read toward harvest or pest action.
Use ToolNew Chill Hours Calculator
Compare your winter's accumulated chill hours against a variety's requirement for a percent-of-need verdict on budbreak reliability.
Use ToolNew Frost Risk Calculator
Read a forecast temperature against your crop's kill point for a damage verdict, frost severity class and cover recommendations.
Use ToolNew Harvest Date Calculator
Add days to maturity to a planting date for a calendar harvest date, with the margin left before first fall frost.
Use ToolNew Succession Planting Calculator
Six staggered sow-and-harvest date pairs from a start date and interval, turning one glut into a season of steady harvests.
Use ToolNew Grain Bin Storage Calculator
Bushels, pounds, tons and floor load for a round bin from diameter and depth, with a safe-moisture margin by grain.
Use ToolNew Planting Calendar by Zone
Pick a crop and your USDA zone band to get its planting window, whether it is a cool or warm-season crop, and its days to maturity — one at-a-glance sowing reference instead of a dozen date calculators.
Use ToolNew Crop Rotation Planner
Build a multi-year bed-by-bed rotation: set your beds and starting families, and the planner cycles each bed through legumes, brassicas, fruits and roots so no crop repeats in place.
Use ToolNew Sun Exposure & Shade Calculator
Model the real sun on your site from latitude, date and what shades it: get solar declination, noon height, day length and peak sun hours, then verify with a stick-and-shadow survey. No map or account needed.
Use ToolNew Carbon Sequestration Calculator
Estimate carbon dioxide stored and absorbed by your trees from trunk diameter, species wood factor and age, with a driving-offset equivalent.
Use ToolNew Corn and Grain Yield Calculator
Estimate a grain harvest from plant count and seeds per plant, then convert it into bushels, weight, per-acre yield and a realistic verdict.
Use ToolNew Stand Basal Area and Stocking Calculator
Work out the basal area of a woodlot from tree count and diameter, compare it with the target for your cover type and size the cut.
Use ToolNew Garden Cost and Savings Estimator
Compare what a garden costs to run against the groceries it replaces, including setup amortisation, inputs and the value of your own hours.
Use ToolNew Calories Per Bed Garden Planner
Plan a garden for food rather than money by working out the calories a bed grows, the days of eating it covers and the ground one person needs.
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