What is the latest suitable time for planting peach trees?
The peach tree is a deciduous small tree of the genus Prunus in the rose family (Rosaceae). Its flowers are ornamental, its fruit is juicy and can be eaten fresh or made into dried peaches, canned peaches, etc., and the kernel can also be eaten. There are many varieties: the nectarine has smooth skin, the flat peach has a flat disc-shaped fruit, and the ornamental peach is a peach tree grown for its flowers. It is widely cultivated in the provinces and regions of China. Let's take a look below at when peach trees should be planted!
Planting time for peach trees
Peach tree planting can be divided into autumn planting and spring planting. Autumn planting is generally done after leaf fall in autumn (which in fact should be entering winter), and a period before the soil freezes is better. There is basically no seedling recovery time, which helps the trees sprout earlier in spring, and the trees grow more vigorously than those planted in spring. Spring planting is generally done after the soil thaws in spring and before the peach buds break, because after planting the root system still needs some time to start growing, which amounts to seedling recovery, so early growth will be somewhat slower, but having passed through the low winter temperatures, it will not suffer freeze damage. In the cold regions of the north, autumn planting can sometimes cause freeze damage such as branch dieback, leading to dead seedlings and so on, and in some places trees are easily lost, so spring planting can also be used.
Grafting time for peach trees
The best time to graft peach trees is mid-March in spring, followed by early to mid-September in autumn. Too early and gummosis is easily produced; too late and the temperature is too low for easy survival. Most farmers prefer to graft in spring and summer. Spring grafting is usually from mid-February to the end of April, when the sap in the rootstock has already risen; the rootstock can be cut off 8-10 cm above the ground and a scion of the variety grafted on using the cut grafting method, and the survival rate of this method can reach over 95%. Summer grafting is from mid-May to early August, when sap flow is vigorous, the peach tree is sprouting and unfolding leaves, and the new buds are not yet plump, making it a good period for bud grafting.
Cultivation techniques for peach trees
1. Raising seedlings: For young seedlings used as rootstock, pinch out the growing tip when the seedling height is 25-30 cm to make the seedling thicker, so that by late summer and early autumn it can reach the thickness required for the rootstock at grafting time. Transplanting is best done in early spring or after leaf fall in autumn. Small seedlings can be transplanted bare-root or dipped in mud slurry; large seedlings need to be transplanted with a soil ball. Cultivating large seedlings requires shaping and pruning to form a framework. Peach trees are generally trained into a natural goblet-shaped crown and a natural open-center-shaped crown.
2. Planting: The planting spacing between rows and plants is 4×5 m or 3×4 m, with 500-840 trees per hectare. Planting can be done anytime from after leaf fall to before bud break. A peach orchard must not be continuously cropped, otherwise young trees will grow noticeably weaker, leaves will lose their green color, new roots will turn brown and branch excessively, and the trunk and branches will exude gum. This replant problem is more serious in sandy soil or soil with low fertility. The main reason is that the residual roots of the previous crop decompose in the soil and produce toxic substances such as benzaldehyde and hydrocyanic acid, which inhibit and poison the root system; it is also related to the multiplication and accumulation of nematodes in the soil under continuous cropping.
3. Fertilizing: The ratio of nitrogen, phosphorus, and potassium required by peaches is about 1:0.5:1. For young trees, care must be taken to control the application of nitrogen fertilizer, otherwise excessive vegetative growth is easily caused. After entering full bearing, increase nitrogen fertilizer to strengthen the tree. The potassium content in peach fruit is 3.2 times that of nitrogen; increasing potassium fertilizer gives larger fruit and higher yield. Bearing trees are fertilized 3 times a year. The base fertilizer is applied in October-November together with deep plowing of the soil, mainly organic fertilizer, accounting for 50% of the annual fertilizer amount. The fruit-swelling fertilizer is applied from late April to May during the fruit pit-hardening stage; for early-maturing varieties, potassium fertilizer is mainly applied, while for mid- and late-maturing varieties, nitrogen accounts for 15-20% of the annual amount, phosphorus 20-30%, and potassium 40%. The post-harvest fertilizer is applied before and after harvest, with the application amount accounting for 15-20% of the annual amount. In addition, the peach orchard needs frequent cultivation and weeding to keep the soil loose, and timely drainage to prevent waterlogging and root rot.
4. Training: Peach trees are mostly trained into a natural open-center shape, with the trunk set at a height of about 60 cm, leaving 3-4 main branches, with the main branches opening at an angle of 50-60°, and each main branch keeping 1-2 sub-main branches as appropriate, while keeping as few small branches as possible on the main and sub-main branches. Pruning periods include winter pruning and summer pruning. Although young bearing trees (3-4 years after planting) have already fruited, they still grow vigorously with many water sprouts and densely growing shoots, so summer pruning measures such as bud removal, tip pinching, and shoot twisting are needed to suppress the strong and support the weak and maintain tree balance. For peach trees in full bearing, after many years of fruiting the tree vigor has gradually moderated, water sprouts and secondary shoots are markedly reduced, and the proportion of medium and short fruit-bearing branches increases, so heading back should be the main approach, while removing overly dense branches and strong terminal branches to improve light conditions among the shoots, and weak branches should be renewed in time.