Claims checked › Claim
Ancient grains are drought-proof
“Old wheats and landraces are naturally drought-proof and will out-perform modern varieties as the climate dries.”
Landraces do lose a smaller share of their yield in a drought, about 10% against 25% for modern cultivars. They start from a base about half as high. Retaining more of less is not more grain, and heritage wheat pays only when a buyer pays two to five times the commodity price.
Where it comes from
A real and well-documented trait, relative yield retention under stress, quoted without its base. Heritage-grain marketing, bakery storytelling and some agroecology advocacy carry the figure forward as "drought-proof".
Who benefits
Heritage seed sellers, artisan flour brands and the bakers whose product story depends on the grain's antiquity. The premium they charge is real and legitimate; the agronomic claim attached to it is not.
What the evidence says
The retention figure is genuine. A 2025 systematic review of 13 studies finds that under drought modern varieties keep about 75% of their yield, evolutionary populations 85%, and landraces 90%, with landraces also higher in protein and lower in rust (Frontiers in Sustainable Food Systems, 2025).
The base is not. In a Mediterranean field comparison of 19 genotypes at semi-arid and Mediterranean sites from 2018 to 2020, modern cultivars out-yielded landraces by 102% across environments (Plants, 2021). Ninety per cent of half is less than seventy-five per cent of the whole. For the hulled wheats the gap is wider: einkorn roughly 1 to 2 t/ha, spelt and emmer 3 to 4, against 8 to 10 for intensive European wheat, 30 to 60% lower (Central European analysis, 2025, as reported). A Chinese field trial comparing a landrace with a 2004 and a 2014 cultivar found the newest cultivar had the deepest roots and the best access to subsoil water (Frontiers in Plant Science, 2017).
The economics decide it. French heritage and population wheats sell to artisan bakers at up to €1,000 a tonne organic against about €200 for conventional wheat in 2024 (La Toque; Réussir). In Ontario in 2023, spelt needed CAD 750 a tonne to match organic wheat's margin and einkorn about CAD 2,000 (Farmtario). With that premium, heritage grain is a good business. Without it, it is a yield cut.
What to say instead
"Landraces lose less, from half the base, and pay only at a premium." If drought stability is the goal, the better-evidenced route is an evolutionary population, which matches modern yields with the lowest variance of any group, or a modern cultivar chosen from your national trial network's dry years. The drought-tolerant varieties page grades all four options.