Melons
Melons, including cantaloupe, honeydew, and watermelon, require precise nutrient management to consistently achieve the sweetness, texture, and storability demanded by the market. Premium fruit quality depends on a balanced fertility program that supports vigorous early vine growth, uniform fruit set, and steady nutrient availability through the bulking stage to maturity. Each developmental stage places specific physiological demands on the crop, making targeted nutrition essential. Tessenderlo Kerley fertilizers supply readily available, crop‑safe nutrients formulated to meet these needs, helping growers produce market‑ready melons with reliable quality. Here are some guidelines for using our products throughout the growing season.
Nitrogen
Nitrogen is essential for vigorous vine growth and canopy development which drives good fruit set in melons. A well‑developed canopy supports sustained photosynthesis, which drives carbohydrate production and ultimately sugar accumulation in the fruit. However, excessive nitrogen later in the growing season can delay maturity, reduce sweetness, and contribute to softer fruit with reduced shelf life.
Controlled‑release nitrogen sources such as N‑Sure®, which contains triazone nitrogen, provide a steady, predictable supply of N when applied through the irrigation system. The triazone molecule breaks down gradually, releasing nitrogen over time to improve uptake efficiency and reduce leaching losses. When blended with conventional N sources like UAN‑32, triazone helps moderate the release pattern and enhances overall nitrogen use efficiency. N‑Sure is also an effective foliar option and can be applied with compatible fertilizers and crop protection products to support in‑season nutritional needs.
Potassium
Potassium plays a central role in melon quality, influencing both sugar accumulation and fruit size. It also enhances stomatal regulation and internal water balance, supporting uniform fruit growth under variable environmental conditions. Liquid potassium fertilizers are well suited for fertigation systems, allowing targeted applications from fruit set through maturity, especially during the rapid fruit‑fill period when potassium demand peaks.
KTS® provides readily available potassium along with thiosulfate sulfur, which improves nutrient uptake efficiency. The thiosulfate component is particularly beneficial in calcareous soils, where its acidifying effect can increase the availability of phosphorus, iron, and manganese.
K‑Row 23® is ideal for early‑season potassium applications because it is seed‑safe and can be placed close to the seed or transplant. It also supports higher in‑season application rates, which is valuable during periods of peak potassium demand. Together, these products allow growers to align potassium supply with crop needs throughout the season, helping ensure consistent melon quality.
Calcium
Ensuring adequate calcium uptake is one of the biggest nutritional challenges for melon growers. Calcium strengthens both rind and flesh, reducing the risk of disorders such as blossom‑end rot and internal breakdown. Because calcium is relatively immobile within the plant, a continuous supply is required during early fruit development to support proper cell wall formation and structural integrity. In sandy soils, common in many melon‑growing regions, calcium availability is often limited due to low cation‑exchange capacity and leaching.
Soluble calcium sources like CaTs® improve calcium uptake by supplying a highly soluble, readily available form of Ca that moves efficiently through the soil profile. The thiosulfate component of CaTs also helps manage high soil pH and can increase the availability of nutrients such as phosphorus and iron. Because CaTs contains no nitrogen, it can be applied during growth stages when additional N should be limited. Additionally, CaTs is an effective tool for in‑season salinity management; soluble calcium helps improve soil physical properties, enhances water infiltration, and supports the leaching fraction needed to move salts below the root zone. By maintaining adequate calcium levels throughout fruit sizing, growers can deliver melons that withstand handling and transport without compromising quality.
Sulfur
Sulfur supports protein synthesis, enzyme activation, and chlorophyll formation, all of which are vital for healthy vine growth and sustained photosynthetic activity. Adequate sulfur also enhances nitrogen use efficiency by improving the balance between amino acid and protein formation. Thio‑Sul® provides a highly soluble, plant‑available source of sulfur that moves efficiently through the soil profile and supports consistent uptake throughout the season. The thiosulfate form, found in Thio-Sul, KTS, and CaTs, also promotes better nutrient mobility and can help mitigate bicarbonate issues in alkaline irrigation water. In high‑pH or calcareous soils, thiosulfate sulfur helps acidify the rhizosphere, improving the availability of nutrients such as phosphorus, iron, and manganese. By maintaining adequate sulfur levels, growers can support balanced nutrition, improved nitrogen efficiency, and the sweetness and flavor profile consumers expect from high‑quality melons.
Protect Melons from Heat Stress and Sunburn
Melon production can be significantly impacted by periods of intense sunlight and high temperatures, particularly as fruit approaches maturity. Excessive heat and solar radiation can increase the risk of sunburn, reducing fruit quality and marketable yield. Heat stress may also affect normal plant function by limiting photosynthesis during critical periods of fruit development. These environmental pressures can result in smaller fruit size, inconsistent maturity, and reduced overall productivity. As growers face increasingly challenging growing conditions, protecting melon crops from heat and sun exposure has become an important part of maintaining fruit quality and maximizing yield potential.
Surround® Agricultural Crop Protectant forms a protective particle film on melon plants and fruit that reflects ultraviolet and infrared radiation. By reducing heat buildup on plant surfaces and fruit, Surround helps protect against sunburn and heat stress. Applications made before heat-related damage occurs can help maintain healthier plant function throughout the season, supporting fruit development and protecting marketable yield potential. When used as part of a season-long program, Surround has also been associated with improved fruit size and more uniform ripening.
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