Table 2.

Agroclimatic variables and their medians for the three categories of values for the variables (low, moderate and high). Each category included one third of the observations

Period	Agroclimatic variable	Category Low median	Category Moderate median	Category High median
Fall hardening period (FH)	Length of fall hardening, days	39	64	99
FH started from the last day when the sum of daily difference between cold degree-days below 5 °C and degree-days above 5 °C was 0 after 1 August and continued to the last day of the first occurrence of minimum air temperatures ≤−10 °C	Accumulation of cold temperatures during FH <5 °C, degree-days	5.7	9.2	12.1
	Mean daily rainfall during FH, mm	1.44	2.03	2.67
Winter period (WP)	Mean daily accumulation of temperature >0 °C during WP, degree-days	0.56	0.77	1.03
WP started from the day following the end of FH and continued to the end of the day before the GP began, which started from the fifth day of the first 5-day spell when daily mean air temperature exceeded 5 °C	Accumulation of cold stress days with temperature <−15 °C, days	5	16	30
Growth period (GP)	Temperature sum >5 °C, degree-days	868	1040	1193
GP started from the fifth day of the first 5-day spell when daily mean air temperature exceeded 5 °C and ended with the last day of harvest	Mean daily temperature sum accumulation rate, degree-days	12.1	13.3	14.4
	Number of days with maximum temperature of 25 °C from GP start to 1st cut, days	0	1	5
	Number of days with maximum temperature of 25 °C from 1st cut to 2nd cut, days	1	5	12
	Accumulation of temperature sum 7 days after 1st cut, degree-days	103	121	141
	Accumulation of precipitation from GP start to 1st cut, mm	49.6	86.8	131.2
	Accumulation of precipitation from 1st cut to 2nd cut, mm	63.2	109.5	175.1
	Accumulation of precipitation 14 days after 1st cut, mm	11.3	29.7	57.2