period of maturity; adolescence; puberty
Refers to the stage of reaching full development, either biologically (puberty/adolescence) or in a broader sense (maturity of a person, organism, or phenomenon). The English glosses 'adolescence' and 'puberty' are narrower biological uses; the core meaning is the period when something becomes mature.
Adolescence is a period of mental and physical maturation.
The maturity period for this variety is autumn.
成熟 is the process or state of maturing; 成熟期 is the period during which that happens.
Compound of 成熟 (maturity) + 期 (period, stage).