The phenological optimum is defined here as a period when most vascular plants in the community are in flower. This period usually corresponds to the period of the peak biomass of vegetation. For vegetation types that have two or more dominant life forms with different phenological optima, the optimum is considered separately for each dominant life form. Some vegetation types (e.g. annual weed or ruderal vegetation) have two or three groups of species with different phenological optima, even within the same life form, resulting in different spring, summer and autumn aspects. Two or three phenological optima are recorded for these types. In the case of marine, some types of aquatic and monocarpic vegetation that may look similar throughout the year or at least throughout the growing season (e. g., Zosterion, Potamogetonion, Ranunculion aquatilis, Littorellion, Greenovion), the phenological optimum is considered to be the time of flowering of the dominant species or most of the species in the community. Phenological optimum categories have been defined primarily based on Central European phenological patterns and applied to vegetation in other regions of Europe. More than one phenological optimum was reported for vegetation types with an optimum that spans more than one category. Assignments to categories were based on field experience, descriptions in various literature sources, and were partially derived from vegetation-plot data.
Early spring – March, April
Late spring – May
Summer – June, July, August
Autumn – August, September, October
Winter – November, December, January, February
Data source and citation
Preislerová, Z. (2022). Phenological optimum. – www.FloraVeg.EU.