Why don’t my harvests match the days to maturity on the seed packet?

Because the seed packet gives one average, measured somewhere else, and your crop grows with your weather: the same carrot can take weeks longer sown in cool April than in June. Heirloom fixes that for you: turn on Use climate-adjusted DTM in a planting and its days to maturity follow your farm’s own climate, day length included.

You get harvest dates you can trust, and your April and July sowings no longer share one number, so your market weeks, tasks and nursery space match what the field will really do. See How climate-adjusted days to maturity work.