The Kreiz Breizh terroir

Trémargat, population 183. Central Brittany: the Argoat, the land of woods, as opposed to the Armor, the land of the sea. The plot lies at an altitude of 755 feet, halfway up the slope.

Granite, not schist

Inland Brittany is easily pictured as schist country. Beneath Trémargat, it is granite: the municipality sits on the edge of the Quintin batholith, emplaced nearly three hundred million years ago. The schist terrain begins farther south.

This granite weathers in place into grus — a sandy material, rich in quartz. That is where the soil of the plot comes from, and it is what drains quickly after rain and warms up early in spring.

The same granite can be seen in the open at the Toul-Goulic gorges, whose right bank belongs to the municipality: there the Blavet disappears beneath a chaos of boulders and re-emerges about a thousand feet farther on, in a wooded, protected valley.

Winter rain

A little over 45 inches of rain falls here each year, on four days out of ten. The figure is impressive, and misleading: this is winter rain. June is the driest month of the year, and summer receives only a sixth of it.

A summer flowering therefore unfolds in the dry part of the year. A fall flowering does not — and that is the whole difference between the House’s growing methods.

No heat waves, no real summer

July and August average around 63 °F. Temperatures pass 86 °F only two days a year, and the gap between day and night stays small. No frost from May to September: the season opens in March and closes in November.

A plant set in the ground here suffers no heat stress; nor is it forced along by heat. What it expresses, it expresses slowly.

Day length governs the rest

At this latitude, the day lasts sixteen hours at the summer solstice and twelve at the fall equinox. A photoperiod plant left in place until its natural maturity switches to flowering only at the end of summer, and is harvested only in mid-October — once the rain has returned.

Light deprivation means bringing that switch forward and harvesting in July or August. The House’s growing methods are not variations of style: they are answers to a day length.

What this climate rules out

The end of the season. October and November each receive more than 4.7 inches of rain, one day in two. An open-field harvest in mid-October takes place as the rain returns, on plants that no longer dry in the field.

This is the constraint that governs everything else: the choice of cultivars, the planting dates, the very existence of the controlled-photoperiod growing methods, and the fact that drying takes place indoors, cold, in a controlled atmosphere — as described in Harvest, drying, curing.

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Climate: Météo-France, Rostrenen station, 1991–2020 normals — seven and a half miles from the plot and twenty feet above it. Geology: BRGM, Carhaix-Plouguer sheet, 1:50,000.

All of the House’s flowers grew in this municipality. See the flowers for sale.