The age at which trees produce their first fruit crop varies according to species, varieties, environmental conditions, management, etc. Some species reproduce after few years while others await several decades before they set flowers and fruits. Plants will often reproduce late or not at all if they grow (or are grown) on the periphery of their geographical distribution or under adverse growth conditions. On the other hand, the physiological maturity can be hastened if the trees are grown under favorable conditions. For some species with a late reproductive age, the reproduction can be hastened by using grafts or cuttings since these vegetative materials tend to retain their physiological age and consequently flower in an earlier age than plants raised from seeds. The position of the tree from where the scions are taken often influences the flowering habit, too.