David Anthes bakes year-round, and the process changes with every season. What works in July does not work in January, and learning to adjust for seasonal conditions took longer than learning most other sourdough fundamentals.
Summer: Heat Is the Primary Variable
Bend summers get warm. Kitchen temperatures in David Anthes’s home regularly reach 75 to 78 degrees Fahrenheit during baking hours in July and August, and fermentation moves quickly at those temperatures. His standard bulk fermentation, which runs around 5 hours in moderate conditions, can complete in 3 to 3.5 hours in summer heat. Missing that window means overfermented dough — slack, sticky, difficult to shape, and prone to spreading rather than rising in the oven.
His summer adjustments are predictable by now. He reduces the amount of starter or levain in his formula by 1 to 2 percent, monitors the dough every 45 minutes during bulk fermentation rather than every hour, and sometimes uses cooler water at mixing to extend the timeline slightly. He also shifts his baking schedule earlier — mixing the night before and cold-retarding longer — to move the active fermentation phase into cooler overnight hours.
Fall: The Most Reliable Season
Fall is David Anthes’s favorite baking season. Temperatures in Bend cool significantly in September and October but remain moderate — kitchen temperatures typically sit between 68 and 72 degrees Fahrenheit, which is close to ideal for sourdough fermentation. The starter is active without being hyperactive, bulk fermentation timelines align well with daylight baking hours, and the lower humidity of high-desert autumn improves crust texture in the oven.
His fall notes show the most consistent results across the year. The loaves are easier to shape, the crumb is more predictable, and the oven spring is reliable. David Anthes uses the fall baking season to calibrate — running through formulas he wants to refine and establishing baseline timings he can then adjust for winter and summer conditions.
Winter: Slowing Everything Down
Central Oregon winters are cold, and an unheated kitchen in January can drop to 62 or 63 degrees Fahrenheit overnight. At those temperatures, fermentation slows substantially. A dough that peaks in 5 hours in fall may take 8 hours or more in winter, and a starter kept in a cool kitchen can lose activity between feedings faster than it would in warmer months.
David Anthes proofs his starter in the warmest part of the kitchen during winter — near the oven or inside the oven with just the light on, which raises the temperature by about 10 degrees. He also feeds his starter more frequently in cold months to maintain its activity level. For bulk fermentation, he uses slightly warmer water at mixing to offset the cool ambient temperature and watches for the same visual and tactile signs of readiness rather than relying on the clock.
Record-Keeping Across Seasons
What makes seasonal adjustment possible is having accurate records from previous years. David Anthes notes the ambient kitchen temperature, the starter condition, the bulk fermentation duration, and the result for every bake. After two years of consistent records, he can look back at a July entry from last year and know roughly what to expect this July. The seasonal patterns become reliable enough to plan around rather than react to.
This is the core of what Notes from the Starter is built on — not the theoretical ideal, but the actual bake, in this kitchen, in this season, with this starter. The record is what turns experience into something usable over time.