Guides & Tools
Everything in the ledger, in one place. Guides explain the reasoning; tools do the arithmetic; records hold the sourced data behind both.
Nothing matches that. Try a crop name, or browse below.
Guides
Does companion planting actually work?
We graded 542 pairings against the literature. What holds up, what doesn't, and where the charts came from.
TimingWhen to start seeds indoors
The count-back chart for every crop, which seeds never to start indoors, and the five mistakes that cost a season.
TimingWhat to plant right now
What can go in the ground this month in your zone — and what it's already too late for.
MethodCrop rotation made simple
Four groups, four beds, one rule. The practice that beats companion planting on evidence.
MethodSquare foot gardening
Plants per square for every crop, plus the three places the method quietly breaks down.
SetupThe best soil for raised beds
What to fill a bed with, in what proportions, why topsoil and pure compost both fail, and how to fill a deep bed cheaply.
ReferenceUSDA hardiness zones explained
What a zone does and does not tell you — including why it can't give you your frost dates.
Tools
Garden Planner
Lay out a bed square by square with live companion conflict checks.
Form GL-2Companion Plant Checker
Tick crops, get a verdict on every pair.
Form GL-3Frost Date Lookup
Your zone, frost dates and season length by ZIP.
Form GL-4Raised Bed Soil Calculator
Bed size to cubic feet, bags and yards.
Form GL-5Plant Spacing Calculator
How many plants fit, three ways.
Form GL-6Planting Calendar
Sow, transplant and harvest windows for your zone.
Reference
All companion planting records
56 crop records, every pairing graded and sourced.
The companion planting chart
The whole ledger on one printable page.
Garden layout plans
Ready-made beds with spacing and conflicts already resolved.
Sources & methodology
How we grade evidence, and which figures are estimates.