Potato

Nitrogen fertilization input can be calculated using the balance method. An excess level of nitrogen will result in an overdevelopment of the vegetation and this could potentially delay tuber initiation. For nitrogen fertilization it is preferable to favor a fractionation in 2 or 3 applications in order to avoid the excesses that are associated with a single application (leaching and excessive incorporation). A more gradual entry of nitrogen also reduces the risk of Alternaria.

 Orthophosphate forms that are immediately assimilable are preferred. For the polyphosphate forms, the chemical properties of the soil (pH and cation contents) will be decisive either for the transformation of phosphorus into assimilable forms or, on the contrary, for the blocking of the phosphorus, in particular by iron, aluminum or calcium.

Apart from stimulating root development, phosphorus is also a key element when it comes to improving the firmness of the potato and reducing damage to the crop.

Phosphorus is considered to be a quality factor in vineyards that helps to produce balanced musts and intense uptake occurs from germination to flowering. It is also considered to be a regulator of plant development and it plays a role in fruit evolution. Phosphorus also promotes the development of roots and is therefore an essential factor in terms of enabling the plants to settle in the first few years after planting.

The form of potassium fertilizer has a direct impact on the quality of the crop. Potatoes are chloride-sensitive and the use of chloride fertilizers may affect germination and can also perturb plant transpiration, in turn affecting growth. Therefore, better results for potatoes are obtained by using chloride free potash sources.

Potassium plays a key role in the absorption of cations. One of its main roles involves the translocation of carbohydrates and proteins to the reserve organs. It is essential for the transfer of assimilates towards the tubers.

Potassium is the key nutrient when it comes to maintaining cell turgor and stomatal regulation.

Potassium is also a key element in terms of helping to improve the resistance of plants against frost and drought and against diseases. This is because it is an activator of several enzymatic systems.

Potassium improves the resistance to damage and reduces the sensitivity to enzymatic browning and blackening after cooking. On the other hand, potassium lowers the content of reducing sugars in the tubers.

The form of the potassium fertilizer plays a significant role in the quality of the harvested potato. For example, potassium chloride and potassium nitrate tend to increase the water content and reduce the dry matter and starch content as compared to potassium sulfate. The differences in the absorption of chloride with respect to sulfate also modify the retention of water. In addition, sulfur and potassium reinforce the emission of adventitious roots in order to promote growth.

Potassium chloride and nitrate fertilizers can suffer leaching, particularly when they are applied prior to planting of the crop (in some cases this can occur up to two months before planting). It is important to understand the cation exchange capacity (CEC) of the soil in order to supply the correct quantities and ratios of nutrients. Furthermore, chloride competes with nitrates and promotes the development of soft tissue. In the field, one can expect issues relating to salinity as well as the sensitivity of the potato to chloride.

Sulfur can be provided in the sulfate or thiosulfate forms. Sulfur tends to induce a higher weight under water of potatoes (Potato Underwater Weight - PUW) as compared to the chloride form.

Sulfur should not be neglected for varieties with often limited PUW and when growing for the production of potato chips, which requires a higher weight underwater.

This effect of calcium also benefits the skin resistance, which results in considerably reduced levels of skin defects. For fresh potatoes, the quality and appearance of the skin (epidermis) is one of the most important factors. This is in addition to the caliber and variety.

Calcium also improves resistance to biotic and abiotic stress and it helps to contribute to the reduction of IBS (“Internal Brown Spot”), which is also known as “brown heart”.

In order to optimize yield and quality, calcium must be readily available in the soil near the stolons and tubers. CaTs®, which contains immediately available calcium, offers the best source of calcium fertilization without nitrate and chloride.

Magnesium must be accompanied by zinc, manganese and boron, which lose their availability with basic pH. In some cases, foliar inputs from the beginning of the growth are justified.

These four elements are involved in the development of the leaf mass and they have a subsequent impact on the quality of the tuberization. They must be available from the beginning of growth in order to fully play their role.

For non-mobile elements (Mn, Zn, S, B), care should be taken to ensure that they are available from the first days of leaf growth. This is because translocation within the plant is severely limited.

It is important to maintain a K/Mg ratio of approximately 3/1 in the soil.

The chloride-free, nitrogen-free formulation of GranuPotasse provides an efficient source of potassium and sulfur, making it ideal for chloride-sensitive crops and high-value production systems. The uniform, free-flowing granules ensure accurate spreading, easy handling and consistent field performance.

By supplying potassium and sulfur in readily available forms, GranuPotasse supports water regulation, enzyme activation, carbohydrate transport and protein synthesis, helping improve crop yield, quality and marketability. It is particularly beneficial for fruit, vegetable and other high-value crops where crop quality, storage life and export potential are essential.

GranuPotasse® is suitable for pre-plant, basal and in-season applications and can be broadcast, banded or incorporated into the soil. It also blends readily with many granular fertilizers, providing growers with a flexible solution for balanced potassium and sulfur nutrition across a wide range of cropping systems.

Its fine crystalline formulation dissolves rapidly and completely, producing a clean spray solution with minimal residue. This makes K-Leaf particularly suitable for precision spraying and for situations in which crops require a rapid supplementary supply of potassium and sulfur.

Applied directly to the foliage, K-Leaf helps prevent or correct potassium and sulfur deficiencies during critical growth stages. Potassium supports water regulation, photosynthesis, carbohydrate movement and crop quality, while sulfur contributes to protein synthesis and essential metabolic processes.

K-Leaf can supplement soil fertilisation when nutrient uptake through the roots is restricted or when crop demand temporarily exceeds soil supply. It is suitable for a wide range of broad-acre, fruit and vegetable crops and can be combined with many compatible soluble fertilisers and crop-protection products following a compatibility test.

By combining both orthophosphate and polyphosphate phosphorus, P-Sure delivers immediately available phosphorus while maintaining phosphorus availability after application. Its excellent physical stability, low salting-out temperature and long storage life make P-Sure an ideal foundation for modern liquid fertilizer programmes.

P-Sure promotes rapid root development, vigorous early crop establishment and efficient nutrient uptake during the critical stages of plant growth. The polyphosphate fraction also helps maintain the availability of micronutrients such as zinc, iron and manganese, supporting balanced nutrition and improved crop performance.

P-Sure is highly compatible with many liquid fertilizers, except calcium-containing products, and is ideal for starter fertilizers, fertigation and custom liquid blends. It combines particularly well with KTS® to produce efficient liquid NPKS formulations, providing growers with a flexible solution for precision crop nutrition.

Each litre of Thio-Sul provides approximately 160 g of nitrogen and 346 g of sulfur, delivering a concentrated and efficient source of both nutrients. Its liquid formulation is easy to handle and integrates readily into modern crop nutrition programmes across a wide range of crops and production systems.

By supplying nitrogen and thiosulfate sulfur together, Thio-Sul helps maintain an appropriate nitrogen-to-sulfur balance, supports protein formation and promotes more efficient use of applied nitrogen. Its sulfur becomes available progressively as thiosulfate is converted in the soil, helping support crop nutrition throughout key growth stages.

Thio-Sul can be applied through irrigation systems, banded, broadcast, injected into the soil or incorporated into compatible liquid fertiliser blends. This application flexibility makes it a practical solution for improving sulfur nutrition and complementing nitrogen fertilisation.

Each litre of KTS supplies approximately 360 g of potash and 252 g of sulfur, providing a highly concentrated source of soluble potassium and sulfur. Its nitrate-free and chloride-free formulation allows potassium to be supplied without adding unnecessary nitrogen or chloride.

Potassium supports water regulation, enzyme activity, carbohydrate transport and the development of crop yield and quality, while sulfur contributes to protein and enzyme formation. KTS is particularly valuable during periods of rapid growth, reproductive development and crop filling, when potassium requirements can increase substantially.

KTS can be used through fertigation, in starter or side-dress programmes, in compatible liquid fertiliser blends and as a foliar treatment on selected crops. Its versatility allows potassium and sulfur to be delivered at critical stages within a wide range of crop nutrition programmes.

Each litre of CaTs supplies approximately 75 g of calcium and 125 g of sulfur, providing both nutrients in a fully soluble liquid form. CaTs combines crop nutrition with soil-management benefits and can be incorporated into a broad range of fertilisation programmes.

Calcium contributes to cell-wall strength, root development and the structural integrity of growing plant tissues, while sulfur supports protein and enzyme formation. A consistent calcium supply is especially important during periods of rapid vegetative growth and fruit development, helping support crop quality, firmness and marketability.

CaTs can be applied through irrigation systems, banded, broadcast or blended with compatible liquid fertilisers. It may also be used as a soil amendment to provide soluble calcium, support soil aggregation and water infiltration, and help manage the effects of excess sodium in saline or sodic soils.