The young tree period is also called vegetative growth period, that is, one year after seedling planting to the initial flowering and fruiting period, during which vegetative growth is absolutely dominant. The growth characteristics of sweet cherry are lengthening, thickening and active growth. The annual growth of branches exceeds 100cm, the thickness exceeds 1.5cm, and there are few branches. The characteristics of substance metabolism are: the nutrient accumulation of trees is late, and it begins to accumulate in September (autumn), and most of the nutrients are used for organ construction. The circulation of nutrients in the tree is simple, which is not conducive to the formation and fruiting of flower buds. Even if many clustered short branches are formed, they cannot become flowers. The length of young tree period is related to rootstocks, varieties, site conditions and management measures. General fruit trees, such as apples and pears, often use light cutting and long putting, branch pulling, girdling, girdling and other methods to slow down vegetative growth and shorten vegetative growth period. However, on the sweet cherry tree, the situation is slightly different. In summer, bud carving and core removal are often used to promote multi-branch and increase the number of branches. Then, by pulling branches, twisting tips and twisting, vegetative growth is inhibited and nutrient accumulation is promoted, so as to shorten the vegetative growth period and promote flower bud differentiation.

2. Early fruiting period

The first fruit period is also called the growth and fruiting period. With the growth of tree age, the crown and root system expand continuously, the number of branches and roots increases exponentially, the order of branches increases, and the growth begins to differentiate; Some peripheral strong branches continue to grow vigorously, and the middle and lower branches stop growing and differentiating ahead of schedule. The decrease of long branches, the increase of medium and short branches and cluster branches, the relative shortening of vegetative growth period, the early accumulation of nutrients and the change of endogenous hormones provide material basis for flower bud differentiation, and the differentiation of buds at the base of medium and short branches and the periphery of cluster branches begins to blossom. However, vegetative growth is still dominant, and the amount of flowers and fruits increases with the increase of branches. Pruning and cultivation management in this period tend to be complicated, that is, while continuing to cultivate the skeleton and expand the crown, we should pay attention to controlling the height of the tree, restraining the tree vigor and promoting the early transition to the full fruit period. On sweet cherry, some measures can be taken to control the growth of the tree, such as twisting the upright tip of the flourishing branch, picking the core for many times, twisting and pulling the flourishing branch, and twisting the flourishing tree in summer. If proper measures are taken, it can enter the full fruit period in 5~7 years. If not, trees over 10 will still flourish and bear no fruit.

3. Full fruiting period

The full fruit period is also called the fruit growth period. The crown reaches the maximum, the growth and fruit tend to be balanced, and the yield is high and stable. The developing branches grow 30~50cm every year, and the stem circumference continues to grow, so that the generated parts cover the whole crown and begin to shift from the inside out to the bottom up. During this period, the rhythm of growth and development is obvious, and the relationship between vegetative growth, fruit development and flower bud differentiation is coordinated, which is the period with the highest economic benefit. Through cultivation measures, this period should be maintained and extended as much as possible, and attention should be paid to improving the illumination in the inner room during pruning to prevent the branches in the inner room from dying and the fruiting parts from moving outward. In the management of soil, fertilizer and water, it can enhance the root activity and prevent the root system from aging, so as to maintain a healthy tree.

4. Aging renewal period

With the growth of tree age, the function of tree body gradually declines, first of all, the root system shrinks, the crown cavity and lower branches wither, the growth weakens, and the yield and quality decline. The arrival time of this period varies with tree species, varieties and cultivation techniques. China cherry has strong natural regeneration ability. When the upper main branch or trunk grows weakly, new branches can be produced at the base to replace the aging branches, and the natural life is longer. A century-old tree can still produce 100 ~ 200 kg per plant. Sweet cherry has a short life span, with a full fruit period of about 20 years, and will obviously age after 40 years. Under natural conditions, the life of sweet cherry can be as long as 80~ 100 years if there are no accidents.