Recently, we have talked with citrus growers about how to refine their nutrient programs to improve yield and quality. No matter the variety of citrus grown, high quality fruit that meets consumer’s expectations is vital to the economic viability of citrus growers in California. Our Southern Central Valley Territory Sales Manager and PCA, Brandon Land, has years of citrus experience and is sharing his general citrus nutrient program with us.
First, it is important for a grower to understand the common nutrient deficiencies in their growing region. Brandon notes that growers in Fresno, Tulare, and Kern counties often have low levels of iron and manganese. Zinc, Boron, Copper and Magnesium are other essential nutrients that are frequently added to spray programs in the area. Your are may be different.
During spring’s vegetative flush, foliar applications of Phosphorous and Potassium are the most effective way to feed these macronutrients to citrus trees. Foliar applications absorb rapidly into leaves and provide nutrients needed to sustain vegetative growth. Tech-Spray Hi-K 0-26-28 is the most effective source of foliar P and K. Brandon suggests adding Tech-Flo All Season, Bloom Blend and/or Tech-Flo Alpha to balance out the nutrient needs during this time.
Bloom and fruit set is the best time to add essential micronutrients like Boron, Molybdenum, Manganese and Zinc as trees are the most “nutrient-hungry” during this time. Providing enough nutrients during this time will ensure the best quality fruit at harvest time.
Manganese is needed in larger quantities to ensure that growth is not limited and that quality of fruit will be optimal. Manganese deficiency is common in soils that have neutral or high pH. Since Manganese is not very mobile in plants, foliar applications every few weeks are the best way to ensure sufficient levels of Manganese. Tech-Flo Mn-15 supplies our highest level of Manganese- 15%.
Zinc is involved in internode elongation and chloroplast development. Tech-Flo MZ 10-6 provides 10% Manganese and 6%
Zinc along with 4% Phosphorous, 2% Potassium, and 1% Sulfur and has great success in influencing zinc and manganese levels in citrus tissue samples. Tech-Flo Beta 0-6-0 has 6.5% of both Zinc and Manganese plus 1 % Calcium and 1.5% Sulfur and is another favorite of citrus growers.
Iron deficiency is common in citrus and results in restricted fruit set and smaller fruit. Iron deficiency delays fruit ripening and harvest, and also effects crop quality. By supplying foliar iron to deficient trees, growers improve the levels of soluble solids in orange and mandarin varieties, producing better quality fruit for their markets. Tech-Flo Phi 2-4-0 supplies 5% Iron and 2.5% Calcium for rapid correction of symptoms.
Brandon notes that our Crop Nutrient Advisor mobile app has some great tools for growers trying to determine the best ways to fertilize crops, and reasons why soil applied fertilizers might not be working. The reference guide that shows soil pH (see below) clearly shows why Iron, Manganese, Boron, Copper and Zinc are better suited for foliar applications in higher pH soils. As soil pH increases, these nutrients become less available.
He also pointed out that cold or water-logged soils, also interfere with availability of nutrients like Iron.
Soil and tissue samples are the best tools in determining specific nutrient needs and are relatively inexpensive to carry out, but growers still need to understand what micronutrients do in order to produce the desired yields and quality fruit they want. If you have struggled with deficiencies in the past, or are simply not producing the quality yields you would like, ask your PCA or Nutrient Technologies Territory Sales Manager about how adding targeted nutrition products can improve your crops and maintain a profitable operation.
For over 30 years our essential nutrient products have been helping growers solve problems in their orchards. Put our experience to work for you.