CLIMATE REQUIREMENTS FOR KIWI CULTIVATION
Temperature requirements
Optimal Growing Temperature: Kiwi plants (Actinidia deliciosa) flourish best in temperate climates. During the growing season, which spans from spring to early nautumn, kiwis thrive in temperatures ranging from 24°C to 29°C (75°F to 85°F). These warm temperatures promote vigorous vegetative growth, flowering, and fruit set. Winter Chill Requirement: A crucial aspect of kiwi cultivation is the need for winter chilling. Kiwis require a specific amount of cold exposure, typically between 0°C and 7°C (32°F to 45°F), for approximately 600-700 hours during the
winter months. This chilling period is essential for breaking dormancy and ensuring synchronized and robust flowering in the spring. Inadequate winter chill can lead to poor bud break and reduced fruit yields.
Frost Sensitivity: While mature kiwi plants can withstand light frosts, severe frosts, particularly during the late spring when the plants are budding and flowering, can be detrimental. Frost damage to young shoots and flowers can significantly impact fruit production. Therefore, it is crucial to select sites with minimal frost risk or implement frost protection measures, such as wind machines or overhead sprinklers, to mitigate frost damage.
Humidity and rainfall
Humidity Levels: Kiwis prefer moderate humidity levels. Excessive humidity can create a favorable environment for fungal diseases, such as botrytis and powdery mildew, which can affect the leaves, flowers, and fruit. Conversely, extremely low humidity can cause stress to the plants, leading to issues like poor pollination and fruit set. Maintaining a balanced humidity level through proper site selection and good airflow is essential for healthy kiwi growth.
Rainfall and Irrigation: Adequate water supply is vital for kiwi plants, especially during the growing season. Kiwis require approximately 800-1000 mm (31-39
inches) of water annually. In regions with insufficient rainfall, supplemental irrigation is necessary to meet the water demands of the plants. Drip irrigation is often preferred, as it delivers water directly to the root zone, reducing water wastage and minimizing the risk of foliar diseases.
Soil Drainage: While sufficient water is crucial, kiwi plants are sensitive to waterlogged conditions. Poorly drained soils can lead to root rot and other diseases. Therefore, selecting well-drained soil is essential. Raised beds or mounds can also improve drainage in areas prone to water logging.
Sunlight requirements
Sunlight Exposure: Kiwis are sun-loving plants and require full sun to partial shade for optimal growth and fruit production. They need at least 6-8 hours of direct sunlight daily. Insufficient sunlight can result in weak growth, poor flowering, and reduced fruit quality. In hot climates, providing some afternoon shade can help prevent heat stress and sunburn on the leaves and fruit.
Wind protection
Shelter from Strong Winds: Kiwi vines are delicate and can be easily damaged by strong winds. Wind can cause physical damage to the vines and flowers, reduce pollination efficiency, and increase the risk of water loss through transpiration. Implementing windbreaks, such as hedges or artificial barriers, around the kiwi orchard can provide protection from prevailing winds. Additionally, trellis systems can support the vines and reduce the impact of wind damage.
Soil preferences
Soil Type: Kiwis thrive in well-drained, fertile soils rich in organic matter. The ideal soil pH range for kiwi cultivation is between 5.5 and 7.0. Soils should be loamy, with good structure and aeration to support healthy root development. Sandy or clayey soils can be improved with organic amendments to enhance drainage and nutrient retention.
Soil Preparation: Before planting, it is important to prepare the soil thoroughly. This involves removing weeds, incorporating organic matter, and ensuring proper soil pH. Regular soil testing can help monitor nutrient levels and guide fertilization practices to maintain soil fertility.
Disease and paste management
Disease Management: Common diseases affecting kiwi plants include bacterial canker, phytophthora root rot, and various fungal infections. Implementing goodcultural practices, such as proper spacing, pruning, and sanitation, can reduce disease incidence. Regular monitoring and timely application of fungicides and other treatments, when necessary, help manage disease outbreaks.
Pest Control: Kiwis can be affected by pests such as scale insects, leaf rollers, and spider mites. Integrated pest management (IPM) strategies, including biological
control, cultural practices, and selective use of pesticides, can effectively manage pest populations and minimize damage to the plants.
Pollination and fruit set
Pollination Requirements: Kiwis are dioecious plants, meaning male and female flowers are on separate plants. Effective pollination requires planting both male and female plants in proximity, typically at a ratio of one male plant for every six to eight female plants. Bees and other pollinators play a crucial role in transferring pollen from male to female flowers, ensuring fruit set.
Flowering and Fruit Development: Flowering occurs in late spring to early summer, and successful pollination results in fruit development. The fruit matures over several months, with harvest typically occurring in late autumn. Proper care during the flowering and fruiting period, including timely irrigation and disease
management, is essential for high-quality fruit production.
