Apples

To optimize apple orchard production, modern solutions to enhance soil fertility and promote tree health is key. Tessenderlo Kerley's liquid fertilizers offer a tailored approach for supplying essential nutrients, fostering robust growth, and ultimately boosting apple yield and quality.

Our liquid fertilizers can address an orchard’s nutrition needs. Our line of products provides essential macro and micro nutrients including nitrogen, potassium, sulfur, and calcium. These nutrients play crucial roles in various physiological processes, from root development to fruit maturation.

Liquid fertilizers make a great fit in many orchards under drip irrigation and microsprinklers. Fertilizer can be injected directly to the rootzone so the tree can utilize the nutrition efficiently and at the right time.

Nitrogen

Nitrogen applications in orchards is a delicate balance. It is an essential nutrient that influences fruit quality and yield. Too much nitrogen at the wrong time can result in unfavorable conditions for a high yielding apple crop. Therefore, following the principles of the 4R’s of nutrient management (Right rate, source, time, and place) is essential. Nitrogen should be applied to ensure an adequate N supply during growth and development.

To apply through the irrigation systems, N-Sure can be blended with another nitrogen source like urea solution or UAN-32 to provide readily available N with the slow-release nitrogen from N-Sure. N-Sure can also be applied via foliar applications at first full leaf and with fungicides and insecticides to supply smaller amounts of N directly to the leaf tissue.

Potassium

Potassium plays a role in fruit quality and yield but is also important in regulating water, potentially reducing winter injury and mitigating drought stress.

KTS® and K-Row 23® are an excellent source of potassium for orchards. KTS provides both K and sulfur (S) in the thiosulfate form. Thiosulfate has been shown to help improve availability of nutrients like phosphorous and micronutrients like manganese, zinc, and iron when applied to the soil. It has also been shown to be an excellent foliar with applications beginning at first full leaf. K-Row 23 contains half the sulfur compared to KTS. Allowing higher application rates and more flexibility in applications of K without acidification of the soil which could be beneficial in orchards with a pH of less than 7.

Calcium

Calcium is important in apples as it plays a role in developing strong cell walls. Having strong cell walls contributes to a higher apple quality including handling storage and reducing internal disease problems such as bitter pit. The timing of a calcium application is critical as is not a mobile nutrient within the plant. CaTs® is a source of soluble calcium that is readily available to the plant. Timing calcium applications prior to bloom up to full bloom to the soil, ensures the roots have enough time to transport calcium to the forming fruit. CaTs is also an effective soil amendment for increasing water infiltration. Applications of CaTs in-season have been shown to improve the soil physical properties and improve water movement into the soil.

How Calcium Can Benefit Apple Growth.

Improve Apple Size and Quality Through Effective Crop Load Management

A heavy bloom can create excessive fruit set, increasing competition among developing apples for water, nutrients, and sunlight. When too many fruit remain on the tree, growers may see reduced fruit size, less uniformity, and lower overall packout quality at harvest. Early crop load management is an important part of maximizing fruit quality and balancing tree productivity. Blossom thinning helps reduce fruit-to-fruit competition before resources are committed to excess fruit, allowing the remaining apples greater access to sunlight and the resources needed for optimal growth and development.

Lime-Sulfur Solution is labeled for apple blossom thinning and can be incorporated into a crop load management program to help regulate fruit set. By reducing the number of blossoms that develop into fruit, growers can improve distribution of resources across the crop and support fruit size and quality objectives. Lime-Sulfur Solution is OMRI-listed and provides growers with an option for blossom thinning as part of their orchard management strategy.

Learn More About Apple Blossom Thinning with Lime-Sulfur Solution

Effective blossom thinning is an important step in managing crop load, improving fruit size, and optimizing apple quality. Explore best practices and learn how Lime-Sulfur Solution fits into an apple thinning program.

Learn more

Managing crop load through timely thinning helps balance fruit numbers with the tree's available resources, supporting both fruit quality and overall orchard performance. Growers often use multiple thinning approaches throughout the season to achieve desired crop load targets and maximize marketable yield potential.

Sevin® can be used as part of an apple thinning program to help manage crop load after bloom. Applied from petal fall through early fruit development and by following all label directions, Sevin provides growers with additional flexibility when blossom thinning opportunities have passed or supplemental thinning is needed. When incorporated into a comprehensive crop load management strategy, Sevin can help growers achieve desirable fruit spacing and support fruit size and quality objectives.

Protect Apples from Sunburn and Heat Stress

Excessive heat and intense sunlight can reduce apple quality and marketability by increasing the risk of sunburn damage and placing additional stress on orchard systems. High fruit and canopy temperatures may affect tree performance and contribute to fruit quality losses during critical stages of development. As growers face increasingly challenging environmental conditions, protecting fruit from heat-related damage is an important part of maintaining packout quality and maximizing marketable yield. Effective heat stress management strategies can help support tree health, improve water-use efficiency, and protect fruit through harvest.

Surround forms a reflective particle film on fruit and plant surfaces that helps reduce the effects of heat and excessive solar radiation. By reflecting infrared and ultraviolet light, Surround helps lower fruit and canopy temperatures, reducing the risk of sunburn while supporting normal plant function. When applied before periods of high heat and maintained through the season, Surround can help protect fruit quality and improve marketable yield potential.

Proven Performance

In a Washington Granny Smith apple trial, Surround reduced sunburned fruit from 40.75% to 13.5% and increased marketable production from 18 to 26 bins per acre. Research also showed fruit surface temperatures can be reduced by 10°F or more during periods of high heat.