Garden with Insight v1.0 Help: potential heat units

The potential heat units for a plant is the number of heat units expected for a typical growing season (from planting date to harvest date) for the cultivar to which the plant belongs. The time to plant maturity is defined empirically, as the time when the plant is usually harvested. For perennial plants, potential heat units are based more on the typical growing season for the plant than any relation to harvest.

Since heat units depend on temperature, the potential heat units for a particular plant depend on the climate in which the plant is grown. The potential heat unit calculation works using normal planting and harvest dates for the cultivar in relation to first and last frost dates. First and last frost dates are calculated as the first and last day in which the minimum (night) temperature falls below freezing.

How it works:
heat unit accumulation and potential heat unit calculation