Feed The Leaves

Feed The Leaves

Foliar feeding is not intended to completely replace soil-applied fertilization of the macronutrients (nitrogen, potassium, and phosphorous). However, macronutrients can be foliarly applied in sufficient quantities to influence both fruit yield and quality. Some crops, like citrus, can have a large part of the nitrogen, potassium, and phosphorous requirements met through foliar applications.

Foliar applications of other plant nutrients (calcium, magnesium, and sulfur) and micronutrients (zinc, manganese, copper, boron, and molybdenum) have proven for many crops to be an excellent means for supplying the plants’ requirements. Soil application of magnesium, manganese, zinc, boron, and molybdenum is not as economical and not as effective as foliar application to supply those nutrients to citrus trees. Applications made to the soil can be subject to leaching, volatilization, and/or being tied up by soil particles in unavailable forms to plants.

Foliar Flexibility

Foliar feeding should be used as an integral part of the annual nutritional program. It can be used in other situations to help plants through short, but critical periods of nutrient demand, such as fruit set and bud differentiation. Foliar nutrition also may prove to be useful at times of soil or environmentally induced nutritional shortages. Leaf application of nutrients is of significant importance when the root system is unable to keep up with crop demand or when the soil has a history of problems that inhibit normal growth.

Foliar feeding is proven to be useful under prolonged spells of wet soil conditions, dry soil conditions, calcareous soil, cold weather, or any other condition that decreases the tree’s ability to take up nutrients when there is a demand. It also may be utilized effectively when a nutritional deficiency is diagnosed. A foliar application is the quickest method of getting the most nutrients into plants. However, if the deficiency can be seen, the crop might have already lost some potential yield.

Several Florida citrus growers and production managers are using foliar nutritional sprays, mainly micronutrients, to slow down decline and maintain adequate fruit productivity of citrus greening-infected trees. Supplemental, balanced foliar nutrition has positive effects on plant diseases by inducing naturally occurring plant resistance mechanisms. It is always important to maintain the balance between nutrients because having one nutrient significantly out of balance can be as bad as a deficiency.

Burn Notice

While foliar feeding has many advantages, it can burn plants at certain rates under certain environmental conditions. It is important to follow the established guidelines for applications. There are a number of conditions that can increase the chances of causing foliar burn. A plant under stress is more susceptible to damage. Stressful conditions include drying winds, disease infestations, and poor soil conditions. The environmental conditions at the time of application also are important factors. Applications when the weather is warm (above 80°F) should be avoided. This means that during warm seasons, applications should be made in the morning or evening.

Additionally, applications should not be at less than two-week intervals to give the plant sufficient time to metabolize the nutrients and deal with the added osmotic stress.

Another important factor when applying nutrients foliarly is to ensure that the pH of the material is in the proper range. The pH range of the spray solution should be between six and seven. Attention should be paid to the pH of the final spray solution. This is significant in areas where water quality is poor.

Post-bloom foliar applications (applied in April when the spring flush leaves are about fully expanded) of potassium nitrate or mono-potassium phosphate have been found to increase fruit yield and size (8 lb. K2O per acre per application).

Leave a Reply

Featured Stories

All Vegetables Stories >All Fruits Stories >All Nuts Stories >All Citrus Stories >

The Latest

BerriesReal Estate Firm, Wish Farms Strike Large Land Deal
October 1, 2014
$13.8 million transaction includes more than 800 acres acquired from longtime Central Florida produce operation. Read More
VegetablesFind The Right Market For Your Crops
October 1, 2014
Getting to know the demographics of your market is key to maximizing your return on investment. Read More
Insect ControlBagrada Bug And Brown Marmorated Stink Bug Posing Threa…
October 1, 2014
Two species of stink bugs are now posing a serious threat to agricultural production in the Western U.S.: the brown Read More
OrganicResearchers Breeding Organic Tomato Varieties Receive $…
October 1, 2014
Purdue University accepts funding to lead multi-institution research to breed organic varieties that will resist foliar diseases. Read More
Vegetables14 Quality Cabbage Varieties [Slideshow]
October 1, 2014
Browse the slideshow below for information on cabbage varieties from the nation’s leading seed breeders and distributors. Read More
FruitsOrganic And Local Food Economies Receive More Than $52 …
October 1, 2014
Most of the grants were authorized through the 2014 Farm Bill. Read More
Insect ControlMore Than 600,000 Acres Removed From Golden Nematode Re…
October 1, 2014
The potato acreage was taken off the Animal and Plant Health Inspection Service’s list; under 6,000 acres in New York are still considered to be infested. Read More
Crop ProtectionTool Helps Track Insects On The Move At Night
October 1, 2014
Signals collected by the National Weather Service’s Doppler radar network may serve as an early warning system to track corn earworm, a major pest in sweet corn. Read More
NutsNew Walnut Budding, Grafting, and Planting Video Releas…
October 1, 2014
Lake County nurseryman Alex Suchan, who has been grafting trees for two-thirds of a century, is the star. Read More
GenNext GrowersGrowers Need To Be Mindful When Dealing With The Media
October 1, 2014
When being interviewed for a story, preparation is the foundation to help you successfully get your point across. Read More
Citrus Achievement AwardSharing Is Caring When It Comes To Curing Citrus Greeni…
October 1, 2014
Mike Sparks, 2014 Citrus Achievement Award winner, says being open with peers about what's working and not working is crucial in managing HLB. Read More
Florida Ag ExpoKnow How To Knock Back Nematodes
October 1, 2014
The 2014 Florida Ag Expo will provide critical tips in soilborne pest management. Read More
CEU SeriesCEU Series: Vow To Vanquish Weeds Among Vegetables
October 1, 2014
Herbicidal neglect can and will kill your crops. Read More
Insect & Disease UpdateUF Names Interim Director For Citrus Research And Educa…
September 30, 2014
Michael Rogers has been a central figure in Florida’s battle to survive greening. Read More
BerriesPractice Persistence When Battling Botrytis In Blueberr…
September 30, 2014
Cognizance of resistance is key to managing formidable fungus. Read More
CitrusFarming Is Quite The Scary Prospect For Some [Opinion]
September 30, 2014
Florida Grower managing editor Paul Rusnak says economic realities might frighten off future leaders from noble professions. Read More
FruitsNew Suppress Herbicide Gets Green Light From EPA
September 30, 2014
Approval gives organic growers new weed management tool. Read More
BerriesNew Fill-By-Weight Clamshell Filler For Blueberries
September 30, 2014
Lakewood Process Machinery's equipment offers a simplified user interface, minimized drop heights, a new dribble-gate system designed for an increased level of accuracy. Read More