Understanding a plant’s root system is fundamental for its successful growth and overall health. Roots anchor the plant, absorb water, and take in essential nutrients from the soil, which are necessary for various physiological processes. For kiwi vines, grasping the nature of their hidden underground network is particularly important for ensuring a thriving plant and a bountiful harvest.
Understanding Kiwi Root Systems
Kiwi vines possess a shallow, fibrous, and extensive root system. A fibrous root system consists of a dense network of fine roots that branch out rather than a single dominant taproot. This structure allows the plant to efficiently absorb water and nutrients from the upper layers of the soil.
While the most active feeding roots are found in the shallow soil, the overall root system of kiwi vines can explore significant soil volumes. This means that while surface conditions are important for nutrient and water uptake, the plant also establishes a deeper, more extensive network for stability and long-term resource acquisition. The ability to spread widely and penetrate to varying depths contributes to the kiwi vine’s vigor and resilience.
Kiwi Root Depth and Spread
Kiwi feeder roots are concentrated within the top 0.5 meters (approximately 1.6 feet) of soil. However, the overall root system of mature kiwi vines can extend much deeper, with roots found at depths greater than 1 meter (3.3 feet) in most orchards. Studies have shown substantial root proportions at 4 meters (13 feet) or more, with some roots even unearthed at depths of 10 meters (33 feet). Half of the total root mass for Actinidia deliciosa can reside within 1.8 to 4 meters (6-13 feet) of depth.
Horizontally, kiwi roots are extensive and spreading. Hardy kiwi (Actinidia arguta) vines can spread between 2.1 to 6.1 meters (7 to 20 feet). Common kiwi (Actinidia deliciosa) and hardy kiwi varieties require ample space, often necessitating planting distances of 3 to 4.5 meters (10-15 feet) between vines to prevent root competition. In established orchards, the root systems of adjacent plants eventually meet, fully exploring the available soil volume.
Caring for Kiwi Roots
Consistent watering is important for kiwi roots, especially given their shallow feeding zone. Providing regular, shallow watering encourages root development in the upper soil where nutrients are readily available. While deep watering once or twice a week may be sufficient during warm weather, avoid overwatering, as kiwi roots are sensitive to waterlogging and can develop root rot in soggy conditions.
Mulching benefits kiwi root health by conserving soil moisture, regulating soil temperature, and suppressing weeds. Applying a 10 to 15 cm (4-6 inch) layer of organic mulch, such as straw, compost, or wood chips, in a 0.6 to 0.9 meter (2-3 foot) circle around the plant helps maintain a stable environment for the roots. This practice also gradually releases nutrients as the organic matter decomposes, feeding the shallow root system.
Proper soil preparation before planting is beneficial. Kiwi vines thrive in well-drained, fertile soil with a slightly acidic pH, ideally between 5.0 and 6.5. Incorporating organic matter like compost or well-rotted manure improves soil structure and fertility. Raised beds can be a good option in areas with poor drainage to prevent root issues.
Protecting the shallow root system from physical disturbance is important. Installing trellises or support structures before planting avoids damaging established roots later. Cultivating or digging deeply around the base of the plant should be avoided to prevent injury to the fine feeder roots. When planting, set the vine at the correct depth, as planting too deep can harm the plant.
Considering their shallow and extensive nature, kiwi roots benefit from surface-applied nutrient management. Kiwi vines are vigorous growers and require a good supply of nitrogen. Applying organic fertilizers or compost around the root zone allows the shallow roots to access nutrients efficiently.