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
Organic potato grower staring at his crops
Crop Protection
August 25, 2016
Better Biocontrol Options Becoming Available To Organic Growers
New bio-based solutions to effectively control weeds and pests are cropping up. Read More
Marty McKenna and Mark Wheeler grab a photo together at the Florida Citrus Industry Annual Conference
Citrus Achievement Award
August 25, 2016
Working Together For A Common Cause Key To Citrus Success
Cirus Achievement Award winner Marty McKenna says the industry is sustained by strength in numbers. Read More
New citrus grove in Florida
Citrus
August 24, 2016
Florida Citrus Granted New Incentive To Grow On
A state-backed $5.5 million grove renovation/re-establishment program is now available and accepting applications. Read More
Judi Whitson, 2016 Florida Woman of the Year in Agriculture
Citrus
August 24, 2016
Meet Florida’s 2016 Woman Of The Year In Agriculture
Dedication to fostering the state’s farming future defines the latest winner of longtime honor. Read More
University of New Hampshire scientists constructed a linkage map of the seven chromosomes of the diploid Fragaria iinumae, which allows them to fill in a piece of the genetic puzzle about the eight sets of chromosomes of the cultivated strawberry.
Berries
August 24, 2016
Researchers Unravel Genetic Ancestry Of Cultivated Strawberry
A genetic analysis conducted by New Hampshire Agricultural Experiment Station researchers aims to improve modern cultivation efforts of strawberry growers. Read More
Justin Clements, a fifth-year doctoral student in the Molecular and Environmental Toxicology Center working in the Department of Entomology at the University of Wisconsin-Madison, is the recipient of NPC's 2016-2017 Academic Scholarship.
Potatoes
August 24, 2016
Fifth-Year Doctoral Student Receives NPC’s Scholarship For Potato Research
The National Potato Council (NPC) has announced that Justin Clements, a fifth-year doctoral student in the Molecular and Environmental Toxicology Read More
2011 WA IFTA Tour
Fruits
August 24, 2016
Don’t Underestimate The Value Of Production Bus Tours For Your Business [Opinion]
Sure, you can see and talk with virtually anyone in the world through your smart phone, but you can’t shake their hand. Read More
Crowd protesting GMOs stock image FEATURE
Farm Management
August 24, 2016
Swaying Views On GMO Foods No Easy Task
Featured speaker for the upcoming FFVA Annual Convention says tides are slowly turning in how people digest the concept of genetic modification. Read More
A subsurface microirrigation system.
(Photo credit: Peter Jacoby)
Grapes
August 23, 2016
Deeper Irrigation Method Showing Promise For Vineyards
A new subsurface irrigation system is showing promise for slashing water usage in vineyards. Many vineyards use drip lines that Read More
Tar spot of corn
Disease Control
August 23, 2016
Florida Sweet Corn Has New Deadly Stalker In Tar Spot
Learn how to identify, the survival and spread, as well as management methods for this disease. Read More
The Latest
Crop Protection
August 25, 2016
Better Biocontrol Options Becoming Avail…
New bio-based solutions to effectively control weeds and pests are cropping up. Read More
Citrus Achievement Award
August 25, 2016
Working Together For A Common Cause Key …
Cirus Achievement Award winner Marty McKenna says the industry is sustained by strength in numbers. Read More
Citrus
August 24, 2016
Florida Citrus Granted New Incentive To …
A state-backed $5.5 million grove renovation/re-establishment program is now available and accepting applications. Read More
Citrus
August 24, 2016
Meet Florida’s 2016 Woman Of The Year In…
Dedication to fostering the state’s farming future defines the latest winner of longtime honor. Read More
Berries
August 24, 2016
Researchers Unravel Genetic Ancestry Of …
A genetic analysis conducted by New Hampshire Agricultural Experiment Station researchers aims to improve modern cultivation efforts of strawberry growers. Read More
Potatoes
August 24, 2016
Fifth-Year Doctoral Student Receives NPC…
The National Potato Council (NPC) has announced that Justin Clements, a fifth-year doctoral student in the Molecular and Environmental Toxicology Read More
Fruits
August 24, 2016
Don’t Underestimate The Value Of P…
Sure, you can see and talk with virtually anyone in the world through your smart phone, but you can’t shake their hand. Read More
Farm Management
August 24, 2016
Swaying Views On GMO Foods No Easy Task
Featured speaker for the upcoming FFVA Annual Convention says tides are slowly turning in how people digest the concept of genetic modification. Read More
Grapes
August 23, 2016
Deeper Irrigation Method Showing Promise…
A new subsurface irrigation system is showing promise for slashing water usage in vineyards. Many vineyards use drip lines that Read More
Disease Control
August 23, 2016
Florida Sweet Corn Has New Deadly Stalke…
Learn how to identify, the survival and spread, as well as management methods for this disease. Read More
Fruits
August 23, 2016
New Insecticides Geared To Give Growers …
Check out three unique chemistries from several of the industry's leading crop protection suppliers. Read More
Apple Grower of the Year
August 22, 2016
Apple Crop Forecasts Live On Twitter
You'll be able to get up-to-the-minute reports of not only the various regions of the U.S., but key production regions around the world. Read More
Oranges
August 22, 2016
Major OJ Purchase Promises Relief For Fl…
$30 million planned acquisition from USDA to be used for surplus removal. Read More
Varieties & Rootstocks
August 22, 2016
Florida Citrus Breeders Squeezed For Tim…
The pressure is on to develop a more HLB-tolerant orange. Read More
Pest Control
August 21, 2016
Spotted Wing Drosophila: For Michigan, …
Why the pest can be so much more destructive for Eastern cherry growers might be due to what they’re not farming. Read More
Grapes
August 19, 2016
European Grapevine Moth Eradicated From …
Agricultural officials confirm eradication of invasive pest, lift quarantine restrictions. Read More
Fruits
August 19, 2016
Parts Of New York Now In Extreme Drought
Water deficits starting to cause concern for fire, water shortages in the Empire State. Read More
Citrus
August 19, 2016
Rough Winter In Store For Much Of The U.…
The Old Farmer’s Almanac and its competitor The Farmers’ Almanac predict the 2016-2017 winter will be cold for much of the country. Read More
[gravityform id="62" title="false" description="false"]