Sources and methods
How the planner’s figures are made, and where each one comes from.
Where the figures come from
Crop timing, yield, spacing, companion and soil figures are typical planning values, not promises for your ground. They are taken, in this order, from:
- Extension: land-grant extension services, UC Master Gardeners, USDA and SARE.
- Research: university trials and production guides. Real measurements, under narrow conditions.
- Industry: seed company charts for market growers, only where nothing else exists, or beside an extension figure as a market-scale comparison.
Every figure is shown with its source in the planner, and you can replace it with your own for any crop or planting. Where sources disagree, both are kept, and nothing is averaged. Home garden and market figures are never merged. Where no source was found, the planner says so instead of filling a number in.
How plants are counted
A row holds the whole number of plants that fit its length at the spacing, with half a spacing clear at each end. That is floor(length / spacing) plants per row. A 10 m row (about 33 ft) at 0.3 m (12 in) holds 33 plants, and three such rows in a bed hold 99. The same rule is used on every screen, in print and in the CSV files.
Companion pairings
Each suggested pairing carries a badge for its evidence: Research, Extension or Traditional. A plant with no sourced guidance says so, and a suggestion never blocks a planting.
Where the figures are strongest
The figures are strongest for coastal California and the Pacific coast today. Growing regions for the rest of the US are being added.
The sources
Every source behind the crop, companion and soil figures, by organization (231 sources). Titles link to the publication.