Nutrient Management Program

Carrots

UF/IFAS fertilization and liming recommendations are advisory in nature and emphasize efficient fertilizer use and environmentally sound nutrient management without losses of yield or crop quality.
It is assumed the nutrients will be supplied from purchased commercial fertilizer and the expected crop yields and quality will be typical of economically viable production.
Growers should consider UF/IFAS recommendations in the context of their entire management strategy, such as return on investment in fertilizer and the benefits of applying organic soil amendments.

Indicated fertilizer rates plus the nutrients already in the soil will satisfy the crop nutrient requirement for this cropping season. Excessive fertilization has been shown to reduce vegetable quality.
On soils that have not been in vegetable production within the past 2 years, or where micronutrients are known to be deficient, apply 5 lb Mn, 3 lb Zn, 4 lb Fe, 3 lb Cu, and 1.5 lb B/A. Use soil testing to monitor micronutrient status every 2 years to avoid micronutrient toxicity, because some micronutrients can build up in the soil. When deciding about micronutrient applications, consider micronutrients added to the crop via fungicides.
Up to 40 lb/acre Mg might be needed when soil test is medium or lower in Mg. Mg can be supplied in fertilizer or from dolomitic limestone, when liming is recommended. Calcium concentrations are typically sufficient in most soils used continuously for vegetable production or where the Mehlich-3 Ca index is >300 ppm. Calcium is added during liming activities and from calcium carbonate present in irrigation water drawn from aquifers in Florida. These sources should be considered in the determination of Ca fertilizer needs.

Nitrogen fertilizer should be applied in approximately 8 split applications to reduce leaching losses and lessen danger of fertilizer burn.
Broadcast all P₂O₅ and micronutrients, if any, and 25% to 30% of the N and K₂O in the bed at planting.
Right placement is an important factor in N use efficiency. Apply remaining N and K₂O in sidedress bands during the early part of the growing season.
Additional, supplemental sidedress applications of 30 lb N/A and 20 lb K₂O/ac should be applied only if rainfall/irrigation amounts exceed 3 inches within a 3-day period or exceed 4 inches within a 7-day period.

Supply 25% to 50% of the N in the nitrate form if soils were treated with multipurpose fumigants or if the soil temperature will stay below 60°F for up to one week following transplanting or germination

Fertilizer and water management are linked. Maximum fertilizer efficiency is achieved only with close attention to water management. Supply only enough irrigation water to satisfy crop requirements. Excess irrigation may result in leaching of N and K, creating possible plant deficiencies.