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All Garden Project Calculators

Every GardenCalc tool in one place. Filter by project type or search for what you are planning. All calculators are free, work in metric or imperial, and show their formula.

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Flowers

Weekly Bouquet Production Planner

Work back from bouquets per week to the flower plants and sowings you need.

Gives youstems/week · plants · sowings · bed area
Flowers

Bouquet Stem Recipe Calculator

Turn a bouquet recipe into an itemised stem shopping list for any number of bouquets.

Gives youstem list · recipe card · totals
Flowers

Wedding & Event Flower Quantity Calculator

Total stems for bouquets, buttonholes, centrepieces and ceremony pieces, split by flower type.

Gives youtotal stems · per piece · focal/filler split
Flowers

Cut-Flower Succession Sowing Planner

Sowing dates for back-to-back flower batches, worked out from the date you want blooms.

Gives yousowing dates · bloom windows · batch count
Flowers

Flower Farm Stem Revenue Estimator

Estimate sales from your cut-flower plants: saleable stems, gross sales and what is left after costs.

Gives yousaleable stems · gross sales · contribution
Flowers

Dried Flower Bunch & Drying Space Calculator

How many bunches your stems make and how much hanging line you need to dry them.

Gives youbunches · drying lines · hanging length
Flowers

Flower Subscription (CSA) Planner

Plan a bouquet subscription: stems to cut each week, bouquets per season and sales.

Gives youstems/week · bouquets · sales
Flowers

Wildflower Meadow Seed Calculator

How much wildflower seed to sow for a meadow patch, border or lawn conversion.

Gives youseed weight · packs · sowing plan
Small space

Vertical Garden Pocket & Soil Calculator

Pocket count, plants and how much potting mix a vertical planter needs.

Gives youpockets · plants · soil · bags
Small space

Window Box Planting Calculator

How many plants fit your window box, with a top-down layout and soil volume.

Gives youplants · layout · soil · bags
Small space

Balcony Container Layout Calculator

How many pots fit your balcony while keeping a clear walkway, with a top-down plan.

Gives youpots · layout plan · growing area · mix
Small space

Grow Bag Soil Mix Calculator

How much soil mix to fill your grow bags, split into compost, base mix and aeration.

Gives youtotal mix · recipe split · bags to buy
Small space

Hanging Basket Plant & Soil Calculator

Trailing and centre plants for any basket size, plus the compost to fill it.

Gives yourim plants · centre plants · compost
Small space

Houseplant Repotting Batch Calculator

Potting mix for a whole repotting day, allowing for the root balls you move across.

Gives youmix per size · total mix · bags
Small space

Self-Watering Container Reservoir Calculator

Days between refills for a self-watering container, based on reservoir size and plant water use.

Gives youdays between refills · water use
Small space

Windowsill Herb Garden Planner

How many herb pots fit your windowsill, how much mix they need and which herbs suit your light.

Gives youpots · mix · herb suggestions
Seed starting

Seed Tape Length & Seed Count Calculator

How much seed tape to make and how many seeds to glue on for your rows.

Gives youtape length · seeds · glue dots
Seed starting

Seedling Shelf & Tray Capacity Calculator

How many seed trays and cells fit on your grow shelf, tier by tier.

Gives youtrays · cells · tiers needed
Seed starting

Seed Starting Mix Batch Calculator

How much seed-starting mix fills your cell trays, split into a homemade recipe.

Gives youtotal mix · recipe split · per tray
Seed starting

Cutting Propagation Batch Calculator

How many cuttings, donor plants and trays you need to end up with a target number of plants.

Gives youcuttings · donor plants · trays
Seed starting

Seedling Pot-Up Soil Calculator

Potting mix, pots and carry trays for potting on a batch of seedlings.

Gives youpotting mix · bags · pots per tray
Seed starting

Bulb & Corm Planting Quantity Calculator

How many tulip, daffodil or crocus bulbs fill a bed, with planting depth and packs to buy.

Gives youbulbs · packs · depth · layout
Seed starting

Microgreens Tray & Seed Calculator

Trays to sow each week and seed to buy for a steady supply of microgreens.

Gives youtrays/week · seed · rotation
Seed starting

Seed Calculator

How many seeds and packets to buy for the plants or rows you want, allowing for germination.

Gives youseeds · packets · spares
Seed starting

Seed Germination Calculator

Your germination rate from a paper-towel test, and how many seeds to sow per plant.

Gives yougermination % · seeds per plant
Seed starting

Seed Rate Calculator

Seeding rate by weight from target plants, thousand-seed weight, germination and establishment.

Gives youkg/ha or lb/acre · total seed
DIY projects

Plant Support, Stake & Cage Quantity Calculator

Stakes, cages, twine and ties for tomatoes, peppers and other tall crops.

Gives youstakes · cages · twine · ties
DIY projects

Garden Trellis Material & Cut-List Calculator

Posts, rails, netting and fasteners for a cucumber, bean or flower trellis.

Gives youposts · rails · netting · cut list
DIY projects

Garden Netting Cover Calculator

What size bird or insect netting to buy for a fruit cage or covered bed.

Gives younet size · panel cut list · clips
DIY projects

Garden Border & Edging Length Calculator

Edging length, pieces, connectors and stakes for square, round or custom beds.

Gives youlength · pieces · connectors · stakes
DIY projects

Row Cover Hoop & Fabric Cut-List Calculator

Hoop lengths, fabric width and length, and pins for low tunnels over raised beds.

Gives youhoops · hoop length · fabric size · pins
DIY projects

Garden Path Gravel Calculator

Gravel, bark or stone for a garden path: volume, weight, bags and weed membrane.

Gives youvolume · weight · bags · membrane
DIY projects

Raised Bed Lumber & Cut-List Calculator

Boards, posts, screws and a cut list for building wooden raised beds.

Gives youboards · cut list · posts · screws
DIY projects

Cold Frame Build Calculator

Lid size, slope angle, boards and hinges for a sloped wooden cold frame.

Gives youlid size · angle · boards · hinges
DIY projects

Compost Bay Build Calculator (Pallets or Boards)

Pallets or boards, posts and capacity for a multi-bay compost system.

Gives youpallets or boards · posts · capacity
DIY projects

Garden Fence for Rabbits & Deer Calculator

Mesh, posts, gate and fixings to fence a vegetable garden against rabbits or deer.

Gives youmesh · rolls · posts · gate
DIY projects

Stepping Stone Path Calculator

How many stepping stones for a path at a comfortable stride, plus bedding sand.

Gives youstones · gaps · sand
DIY projects

Shade Cloth Size Calculator

Shade cloth size, clips and shade percentage for beds, hoops and pergolas.

Gives youcloth size · clips · shade %
Harvest planning

Family Vegetable Planting Calculator

How many plants of each vegetable to grow for your household, and the space they take.

Gives youplants · weekly harvest · bed area
Harvest planning

Weekly Salad Garden Planner

How many salad plants to sow, and how often, for a steady weekly harvest.

Gives youplants per sowing · schedule · bed area
Harvest planning

Kitchen Herb Harvest Calculator

How many basil, parsley or mint plants to grow for the herbs you use each week.

Gives youplants · space · resowings
Harvest planning

Seed Saving Reserve Calculator

Seeds, pods or fruits to save for next year's planting, with germination and a reserve.

Gives youseeds · pods or fruits · plants to save from
Harvest planning

Garlic Planting Calculator

Seed garlic bulbs, cloves, rows and bed space for the harvest you want.

Gives youseed bulbs · cloves · rows · area
Harvest planning

Seed Potato Calculator

Weight of seed potatoes for your rows, number of plants and expected harvest.

Gives youseed weight · plants · harvest
Harvest planning

Berry Plants Per Person Calculator

How many strawberry, raspberry or blueberry plants to grow for your household.

Gives youplants · harvest · space
Harvest planning

Crop Yield Calculator

Expected harvest from your bed and its value at shop prices.

Gives youharvest weight · value
Harvest planning

Companion Planting Calculator

Check whether two crops are traditional companions, and see every pairing for a crop.

Gives youverdict · companions · plants to avoid
Harvest planning

Crop Rotation Calculator

A bed-by-year crop rotation plan for your vegetable beds.

Gives youbed-by-year table · groups
Soil & mulch

Raised Bed Soil Calculator

How much soil mix fills your raised beds, split into topsoil, compost and aeration.

Gives youvolume · mix · bags · bulk
Soil & mulch

Topsoil Calculator

How much topsoil to order for a lawn, bed or level-up, by volume, weight or bag.

Gives youvolume · weight · bags
Soil & mulch

Mulch Calculator

Bags or bulk mulch for your beds and borders at the depth you choose.

Gives youvolume · bags · coverage
Soil & mulch

Compost Calculator

Compost for top-dressing, new beds or lawns, in bags or bulk.

Gives youvolume · bags · weight
Soil & mulch

Potting Soil Calculator

Potting soil for several container sizes at once, with bags to buy.

Gives youvolume per pot · total · bags
Soil & mulch

Soil Amendment Calculator

How thick a layer of compost or other amendment to spread to reach a target mix.

Gives youlayer depth · volume · bags
Soil & mulch

Garden Volume Calculator

The volume of any bed, planter or hole in litres, cubic feet, cubic yards and cubic metres.

Gives youlitres · cu ft · cu yd · bags
Soil & mulch

Soil Calculator

Volume, weight, bags and truck loads for soil, compost, sand or gravel.

Gives youvolume · weight · bags · loads
Soil & mulch

Topsoil Weight to Cubic Feet Calculator

Convert a bag of topsoil, soil or mulch between pounds, kilograms, cubic feet and litres.

Gives youcu ft · litres · lb · bags per yard
Soil & mulch

Compost C:N Ratio Calculator

The carbon-to-nitrogen ratio of your compost mix, and how many browns to add for 30:1.

Gives youC:N ratio · browns to add
Spacing

Square Foot Garden Planner

Plan a square foot garden grid: squares per crop, plants per square and a coloured layout.

Gives yougrid layout · plants · free squares
Spacing

Plant Spacing Calculator

How many plants fit a bed in a square grid, rows or triangular pattern, with a plan view.

Gives youplants · rows · layout
Spacing

Plants per Square Foot Calculator

Plant density per square foot or square metre for any spacing, plus a quick reference table.

Gives youdensity · total · table
Spacing

Garden Area Calculator

Area of a garden made of rectangles, circles, triangles and ovals, in any unit.

Gives youarea · acres · conversions
Spacing

Garden Bed & Path Layout Calculator

How many beds and paths fit your plot, with growing area and a plan view.

Gives youbeds · growing area · plan
Spacing

Flower Bed Plant Calculator

Plants for a flower bed in back, middle and front zones, each at its own spacing.

Gives youplants per zone · total
Spacing

Plant Population Calculator

Plants per acre, hectare and square metre from row and in-row spacing.

Gives youper acre / ha · total plants · seeds
Spacing

Plants Per Acre Calculator

How many plants fit an acre or hectare at square or triangular spacing.

Gives youplants per acre · total · layout gain
Spacing

Crop Spacing Calculator

Recommended spacing for 14 vegetables and how many fit your bed, in rows or offset.

Gives youplants per bed · spacing · plan
Spacing

Row Spacing Calculator

How many rows fit a bed at your spacing, or the spacing for a set number of rows.

Gives yourows · spacing · total row length
Spacing

Ground Cover Calculator

How many ground cover plants and flats you need for an area at your spacing.

Gives youplants · flats · plants per sq ft
Water

Rain Barrel & Rainwater Harvesting Calculator

Rainwater collected from your roof per storm and per year, and how many barrels to fill.

Gives youlitres or gallons · barrels
Water

Watering Schedule Calculator

How much to water each week after rain, split into sessions that suit your soil.

Gives youweekly water · sessions · minutes
Water

Irrigation Scheduling Calculator

How many days between irrigations and how much to apply, from soil, roots and ET.

Gives youinterval · net depth · gross depth
Water

Irrigation Run Time Calculator

How many minutes to run each zone to apply the depth of water you want.

Gives youminutes per zone · weekly time
Water

Sprinkler Calculator

How many sprinkler heads a rectangular lawn needs, which types, and how many zones.

Gives youheads · layout · zones
Water

Sprinkler Coverage Calculator

Area one head covers and the precipitation rate of your layout, with time to apply water.

Gives youcoverage · precipitation rate · run time
Water

Drip Irrigation Planner

Emitters, drip line and fittings for your rows, with total flow and zones.

Gives youemitters · tubing · zones · parts
Water

Drip Emitter Calculator

How long to run drip emitters to give each plant the water it needs.

Gives yourun time · emitters · flow
Water

Drip Flow Rate Calculator

Total flow of your drip system and whether your tubing can carry it.

Gives youtotal flow · capacity used
Water

Drip Irrigation Pump Calculator

The flow, total head and power a pump needs to run your drip system from a tank or well.

Gives youflow · total head · power
Water

Rainwater Calculator

How much rainwater your roof collects a year and per storm, and how long it lasts.

Gives youlitres or gallons per year · per storm
Water

Crop Water Requirement Calculator

Daily and weekly water use of a crop from reference ET and its crop coefficient.

Gives youdaily use · weekly use · net after rain
Water

Evapotranspiration Calculator

Estimate daily reference evapotranspiration from temperature, latitude and date.

Gives youET₀ per day · per week
Lawn

Grass Seed Calculator

Grass seed for a new lawn or overseeding, by grass type and area.

Gives youseed weight · bags · rate
Lawn

Sod & Turf Calculator

Sod or turf rolls and pallets for your lawn area, with cutting waste.

Gives yourolls · pallets · area
Lawn

Lawn Fertilizer Calculator

Fertilizer per feed and per year for your lawn, with the spreader rate and bags.

Gives youper feed · spreader rate · bags
Fertilizer

Soil pH Calculator

How much lime to raise, or sulfur to lower, your soil pH to the level your plants need.

Gives youlime or sulfur · rate · applications
Fertilizer

Lime Application Calculator

Turn a soil-test lime recommendation into the product rate and bags for your lime.

Gives youproduct rate · bags · applications
Fertilizer

Gypsum Calculator

Gypsum for clay or salt-affected soil, with the calcium and sulfur it supplies.

Gives yougypsum · bags · calcium · sulfur
Fertilizer

Manure Application Calculator

How much manure to spread for the nitrogen your crops need, by weight, volume and loads.

Gives youweight · volume · loads · nitrogen
Fertilizer

Organic Fertilizer Calculator

How much blood, bone, fish, kelp or alfalfa meal to apply for your nutrient target.

Gives youproduct · rate · N-P-K supplied
Fertilizer

Nitrogen Calculator

How much urea, ammonium sulfate or other nitrogen fertilizer gives the actual N you need.

Gives youproduct · rate · splits
Fertilizer

Phosphorus Calculator

Turn a phosphate (P₂O₅) or phosphorus target into superphosphate, MAP, DAP or bone meal.

Gives youproduct · rate · N supplied
Fertilizer

Potassium Calculator

Turn a potash (K₂O) or potassium target into sulfate of potash, muriate or wood ash.

Gives youproduct · rate · N supplied
Fertilizer

Fertilizer Requirement Calculator

How much of an N-P-K fertilizer meets your nutrient targets, and what is left over or short.

Gives youproduct · N-P-K supplied · gaps
Fertilizer

Fertilizer Mixer

How much liquid concentrate or soluble powder to mix into your watering can or tank.

Gives youdose · dilution · ppm
Fertilizer

Soil Texture Calculator

Your USDA soil texture class from sand, silt and clay percentages or a jar test.

Gives youtexture class · triangle · advice
Fertilizer

Soil Organic Matter Calculator

How much compost raises your soil organic matter from its tested level to a target.

Gives youcompost volume · layer · bags
Fertilizer

Soil Moisture Calculator

Soil water content from a wet and dry sample, and how much water refills the root zone.

Gives youwater content · available water · refill
Fertilizer

Soil Drainage Calculator

Your soil's drainage rate from a simple percolation test, with what it means for planting.

Gives youdrainage rate · perc rate · verdict
Indoor

Greenhouse Calculator

The heater size your greenhouse needs to stay frost-free on the coldest nights.

Gives youheater kW / BTU · heat loss
Indoor

Greenhouse Size Calculator

The greenhouse footprint you need for your trays and pots, with benches and a path.

Gives youlength × width · bench space · plan
Indoor

Grow Light Calculator

LED wattage, daily light integral and running cost for your grow area and crop.

Gives youwatts · DLI · cost
Indoor

VPD Calculator

Leaf vapour pressure deficit from temperature and humidity, and the humidity to aim for.

Gives youVPD kPa · zone · target humidity
Indoor

DWC Calculator

Nutrient solution, nutrient doses and air pump size for deep water culture buckets.

Gives yousolution · nutrients · air pump
Indoor

Aeroponics Calculator

Pump flow, misting cycles and reservoir life for low- or high-pressure aeroponics.

Gives youpump flow · cycles · top-ups
Indoor

Hydroponic System Cost Calculator

Setup and monthly running cost of a hydroponic garden, per month, year and plant.

Gives youmonthly cost · year one · per plant
Indoor

Greenhouse Cost Calculator

Typical cost to build a greenhouse by size and type, with base, extras and yearly heating.

Gives youbuild cost · per sq ft · heating
Timing

Last Frost Date Calculator

Your average last spring frost and the safe dates to sow and plant out.

Gives yousafe date · spring timeline
Timing

First Frost Date Calculator

Your average first autumn frost and the last dates to sow crops so they mature in time.

Gives yousow-by date · fall crop table
Timing

Planting Calendar

A personal sowing and planting calendar for 19 vegetables from your frost dates.

Gives youindoor sowing · planting out · autumn sowing
Timing

Transplant Date Calculator

When to sow indoors, harden off and transplant seedlings from your last frost date.

Gives yousow date · harden off · transplant
Timing

Harvest Date Calculator

When your crop will be ready to pick, from planting date and days to maturity.

Gives youfirst harvest · harvest window
Timing

Growing Degree Days Calculator

Daily and total growing degree days, and how long until your crop's GDD target.

Gives youGDD per day · total · days to target
Timing

Chill Hours Calculator

Estimated winter chill hours or Utah chill units, compared with your fruit variety's need.

Gives youchill hours · variety check
Timing

Sun Exposure Calculator

Whether your spot is full sun, part sun, part shade or shade, and what grows there.

Gives yousun category · day length · plant ideas
Trees & costs

Tree Spacing Calculator

How many trees fit your plot at square or triangular spacing, with a layout plan.

Gives youtrees · density · layout
Trees & costs

Tree Age Calculator

Estimate a tree's age from trunk circumference and its species growth factor.

Gives youage · diameter
Trees & costs

Oak Tree Value Calculator

An indicative landscape value for an oak using the trunk formula method.

Gives youappraised value · basic value
Trees & costs

Black Walnut Value Calculator

Board feet (Doyle rule) and an indicative timber value for black walnut logs.

Gives youboard feet · value
Trees & costs

Tree Removal Cost Calculator

An estimated price range to remove a tree, with stump grinding and haul-away.

Gives youprice range · breakdown
Trees & costs

Tree Trimming Cost Calculator

An estimated price range to prune or trim your trees by size, condition and access.

Gives youprice range · per tree
Trees & costs

Land Clearing Cost Calculator

An estimated cost range to clear brush or woodland, per acre or hectare.

Gives youtotal range · per acre
Trees & costs

Acres Per Hour Calculator

How many acres or hectares per hour a mower, tiller or sprayer covers, and how long a job takes.

Gives youacres or ha per hour · job time
Trees & costs

Garden Cost Estimator

The cost of setting up raised beds: frames, soil, plants, seeds and extras.

Gives youtotal · per area · budget table