Key Techniques for Summer Orchard Management of Kiwifruit
July and August are the hottest period of the whole year, and also the period when kiwifruit begins its second fruit enlargement and quality formation; this period is the most important for the growth and nutrient accumulation of kiwifruit. However, summer brings high temperatures and abundant rain, and orchard management gradually becomes more important; once neglected, it can easily lead to pests, diseases and heat damage. So how to properly manage the orchard is very important. Let's take a look below!
1. Preventing Sunburn
High temperatures can easily sunburn kiwifruit. During this hottest period, the most important thing is to prevent kiwifruit from being sunburned by direct sunlight. Before this period arrives, plant some cover grass in the orchard; cover grass can effectively lower the orchard temperature. Experiments have shown that the temperature in an orchard without cover grass can reach above 40 degrees, while the temperature in an orchard with cover grass can be lowered by at least 8 degrees, so cover grass is quite effective in preventing sunburn. When removing leaves, do not remove all the old leaves above the fruit, because old leaves can shield the fruit from sunlight and reduce the intensity of direct sunlight.
2. Fertilizer and Water Management
July is when kiwifruit needs water and fertilizer the most, and also an important period for the accumulation of dry matter inside the fruit. It is a critical time for the growth and development of kiwifruit trees; the second enlargement, new shoot growth and so on all require large amounts of water and fertilizer, so during summer the fertilizer and water supply in the orchard must be ensured. The main fertilizer is the fruit-quality fertilizer, which is the last fertilization before harvest, but the amount of nitrogen fertilizer should be controlled, with phosphorus and potassium fertilizers as the main focus. Moreover, summer can easily make the orchard dry, so at this time attention should be paid to irrigation and drainage in the orchard. Lack of water will make the fruit shrivel, and severe water shortage is a problem, but water should not accumulate in the soil, as waterlogging can easily cause oxygen deficiency in the soil and affect root respiration.
3. Trellis Management
At this time, new shoots that were not pinched in the earlier period should be thinned and tipped to prevent the new shoots from growing too vigorously upward. Crossing shoots, poorly nourished branches and some pest- and disease-damaged shoots should be cut off. Water sprouts on the main and secondary vines should be thinned in time to inhibit their growth, but attention should be paid to the number of buds retained; those not retained should be budded off immediately to avoid affecting the thickening growth of grafted branches. The main issue is that the probability of heat damage will increase, so remove more of the leaves growing in the inner layers to avoid competing for nutrients with other normally growing leaves and the fruit.
4. Disease Control
The main diseases of kiwifruit include anthracnose, brown spot and other fungal diseases. The best method is prevention in advance and good trellis management. The air permeability of the trellis should be ensured, and for orchards prone to disease, pesticides should be rotated to keep the incidence of disease under control. Summer is also the season when many pests are active, such as scarab beetles. The most important way to prevent pest damage is to reduce the adult population. Reduce insect eggs to reduce the number of adults the following year; adults can be trapped and killed by methods such as light trapping.
The above are the management matters to note for kiwifruit in summer. Sunburn is very common; last year, high temperatures and drought even caused kiwifruit disasters. Be sure to reduce direct sunlight on kiwifruit, water frequently, and keep the tree in a moist state. Pests and diseases are also very troublesome problems; take preventive measures and try to reduce the incidence of all diseases to a minimum.