Onions, garlic and other bulbs are grown on soil textures ranging from sandy to clay loams. Sandy soils are advantageous for onions and bulbs because there is less risk of bulb disease problems when fields are dry at harvest time. However, they do require more frequent irrigation, and nitrogen leaching is more of a concern than in other soils. By adjusting the irrigation frequency according to crop demand, and by frequent use of Fusion soluble fertiliser or an initial application of Impact controlled release fertilisers applications, growers can usually produce optimum yields on sandy soils.
Onions, Leeks & Garlic - Onions and garlic require adequate zinc to be present, particularly at early crops stages, otherwise the bulb will not form properly. At this time foliar sprays of Solar Zn or IndiPlex Zn should be planned into the overall fertiliser programme. The use of IndiPlex Zn will also give additional sulphur to the crop which has been shown to enhance intensity of taste. On specific soils copper deficiency can occur and again foliar applications of Solar Cu or IndiPlex Cu should be made. Onion seedlings respond to early applications of amine or ammonium nitrogen, particularly in conjunction with calcium and soil applications of Impact Controlled Release Fertilisers will satisfy this requirement.
Beans & Peas - Leguminous beans and peas are able to fix nitrogen from the soil and often their requirements for applied major nutrients are low. However, other nutritional needs should not be ignored and micronutrient deficiencies such as manganese, zinc and boron can be of local importance. Manganese deficiency in particular can lead to internal browning of the seeds and subsequent loss of quality and marketability. Foliar applications of Fusion or Solar micronutrients can overcome problems associated with lack of soil availability of micronutrients, leading to increased yield and quality both of fresh pods and seeds. Most leguminous crops require potassium early in their development but high soil applications can affect germination and seedling growth. Foliar applications of Solar K32 will avoid any crop check. Applications of Numerica Ultra in legumes will increase the plant natural resistance to diseases such as downey mildew, whilst organic products such as Protaplex and Joust will help plants resist the effects of environmental stress such as drought or heat.