Foliar feeding using soluble products is an effective method of providing nutrients to a plant and can help to improve the production of upland vegetables from the latest issue of Far Eastern Agriculture, available online from 23rd August
Rich volcanic soil, ample rainfall and an equitable climate are the core advantages of growing vegetable crops in the tropical highlands. However, the naturally high soil fertility of upland soils in the tropics is not enough on its own is satisfy the nutrient demands of fast growing vegetable crops. Fertiliser application is a crucially important component of any cultivation schedule.
Whether it be leaf crops (head cabbage, kale, pak choy and lettuce); fruit crops (tomato, sweet pepper, cucumber, aubergine); or root crops (potato, carrot, onion and garlic), the spray application of soluble nutrients is the most efficient and targeted way of satisfying the nutritional needs of vegetable crops. Foliar feeding using soluble products is almost twice as effective in getting nutrients into a plant compared with the equivalent amount applied as base fertiliser to the soil.
The first and foremost concern amongst growers relates to the assumed wash-off effects of frequent and intense rainfall on soluble nutrients deposited by spraying on foliar surfaces. However, an important component of the high performance of foliar sprays of soluble nutrients is the speed with which the individual ions (eg, NO3-, Ca2+ and Zn2+) pass into the plant and integrate into the metabolism. Provided the foliar spraying takes place during a suitably dry weather window, the nutrients will have sufficient time to make their way into the plant.
Once inside, they are safe and available for use, unlike soil-applied solid fertiliser that is subject to continual solubilisation and leaching from the soil. It is worth pointing out that amounts of solid fertiliser applied to soil, compared with soluble nutrients applied by foliar spraying, is necessarily large precisely because of continual solubilisation and leaching with comparatively little taken up from the soil and used by the plant roots.
"Vegetable growers who avoid foliar feeding are missing out on a range of key plant nutritional benefits," managing director Peter Prentis at Omex said while commenting on the advantages of the practise.
