Potassium Is Important In Almonds

Staying vigilant to maintaining almond orchard nutrition is the best way growers can avoid eventual depletion of important nutrients like potassium (K), which plays a major role in many plant processes, says David Doll, a pomology farm adviser for University of California-Davis (UC-Davis) in Merced County, CA.

“Potassium promotes root growth, increases kernel and fruit size, and provides key metabolic features including the formation of starch, translocation of sugars, stomata regulation, and the formation of xylem vessels,” Doll says.

Removing almond hulls and kernels during harvest also removes significant amounts of potassium from almond orchards, but depletion can be avoided by regularly applying potassium to the soil.

“Tissue analysis has shown that almond hulls and kernels are about 3% and 1% potassium, respectively, so for every 1,000 pounds of kernel meats harvested, about 50 pounds of potassium are removed,” Doll says. “Soil application of potassium is the most effective way to deliver potassium to the tree. Ensuring that the amount of potassium removed from the orchard is replaced will help maintain high yields.”

Growers can ensure that they keep their almond orchards in top health through proper fertilization of their trees, according to Doll.

“A balanced fertility program is critical to maintaining a healthy orchard, environment, and wallet,” he says. “Since potassium reacts differently than nitrogen in the soil, applications need to be placed in the right amounts at the right place at the right time. Potassium should be applied annually to rebuild levels; and even though tissue and soil analysis can be expensive, it can quickly pay for itself by preventing a deficiency.”

Leaf Sampling And Fertilization

Plants that are potassium-deficient grow slower and have small, pale leaves, and trees that are severely deficient may have necrotic tips and margins. In many cases the leaf tip curls upwards in a common symptom named Viking’s Prow, according to Doll. Foliar fertilizer applications can be used to address an in-season problem, but are not adequate to address long-term potassium deficiency, he says.

“I try to get growers to think of foliar sprays like a crutch,” he says. “Foliar sprays are often noted to perk the tree up, and they do, but this effect is relatively short-lived if the tree is deficient in vital nutrients. Within almonds, it would be very expensive to apply the annual potassium needs of a tree through foliar nutrient applications, considering a 3,000-pound crop requires the application of at least 150 pounds of K. The biggest bang for your buck comes from soil applications.”

While depletion of soil potassium doesn’t happen overnight, or even over just one season, long-term effects of potassium deficiency will cause yield loss, Doll says.

“Reduced crop load, loss of fruiting wood or spurs, and poor tree growth are all caused by long-term potassium deficiency,” he says. “Usually yield loss is gradual and once the trees show signs of deficiency, yield has already been lost.”

This is why regular potassium leaf and soil sampling are so critical to maintain healthy almond orchards, Doll stresses.

“Annual mid-July leaf sampling from non-fruiting spurs will allow growers to compare leaf potassium levels with UC standard guidelines,” he says. “Leaf K levels should range from 1.4% to 1.8%. Leaves are deficient if potassium levels are below 1.4% and no growth benefit has been observed with leaf potassium levels higher than 1.8%.”

Growers must remember that potassium levels will be lower in fruiting spurs and in leaves at the top of the tree, which is why growers see a positive effect of leaf K levels higher than 1.4%, Doll says. “In other words, just because the leaves you sampled are at 1.4% doesn’t mean the leaves at the top of the tree or fruiting spurs are at 1.4%; they are usually lower, therefore deficient and negatively impacted for the coming year.”

Performing soil analysis tests every three years will allow growers to track soil potassium levels. Potassium within the soil will gradually drop with every crop load if no potassium fertilizer is added, and once it drops, it will take several years of large applications to bring the levels back to normal. Continued monitoring and fertilization will help growers build soil potassium levels, according to Doll.

“Since potassium binds easily with soil exchange sites, it does not move readily in the soil; therefore, potassium must be delivered as closely as possible to the root system,” he says. “Placing a band of fertilizer within the irrigation wetting zone will help move the fertilizer into the soil. Dormant season applications can also be made. Since potassium does not leach from the soil profile like nitrogen, winter rains can move the nutrient into the rooting zone.”

Leave a Reply

2 comments on “Potassium Is Important In Almonds

Nuts Stories
The new Greefa unit at Stemilt is nearly the length of a football field. “It just keeps going and going,” says General Manager Jay Fulbright. (Photo courtesy of Stemilt)
Citrus
September 20, 2016
Preventative Control Rules Now In Effect For Large Businesses
Facilities employing 500 or more people must meet new standards. Read More
If Palmer amaranth is present in your field, do not remove the weed plants. Instead, destroy the weeds by burying or burning near the infested field.
Photo credit: Dwight Lingenfelter, Penn State University
Citrus
September 20, 2016
EPA Says Glyphosate Not Likely To Cause Cancer
Paper says herbicide not carcinogenic at doses relevant for human health risk assessment. Read More
NASA's global temperature heat map for 2015
Citrus
September 17, 2016
August Was The Hottest In 136 Years
The extended heat wave continues a streak of 11 consecutive months of record-setting temperatures. Read More
8-10-san-luis-reservoir-california
Fruits
September 15, 2016
California Growers May Face More Water Cuts
State proposal would divert more water to San Joaquin River system to save endangered fish habitat. Read More
(Photo credit: Wikimedia Commons)
Citrus
September 15, 2016
What The Bayer-Monsanto Merger Means Thus Far
The deal, subject to regulatory approval, would create the world’s largest agriculture company. Read More
Split view of Monsanto and Bayer company signage
Citrus
September 14, 2016
Bayer Acquires Monsanto After Months Of Negotiations
Mega-Merger sealed with $66 billion all-cash transaction. Read More
Illustration of CRISPR-Cas9
Citrus
September 13, 2016
Can CRISPR Carry Agriculture Innovation To The Next Level?
Game-changing technology allows targeted gene modification to fight diseases like citrus greening. Read More
The Latest
Nuts
September 29, 2016
Use Soil Sampling To Inform Your Almond …
Whether planting on new ground or replanting, sizing up the enemy — nematodes — is a must. Read More
Citrus
September 29, 2016
Winter Is Coming, And It Could Get Wicke…
Forecast sees heightened freeze threat for Florida citrus; frequent snow to blast Northeast. Read More
Citrus
September 22, 2016
Senate Committee Report Says WOTUS Refor…
A report issued from the Senate Environment and Public Works (EPW) Committee says federal agencies overreach their authority to regulate Read More
Citrus
September 20, 2016
Preventative Control Rules Now In Effect…
Facilities employing 500 or more people must meet new standards. Read More
Citrus
September 20, 2016
EPA Says Glyphosate Not Likely To Cause …
Paper says herbicide not carcinogenic at doses relevant for human health risk assessment. Read More
Citrus
September 17, 2016
August Was The Hottest In 136 Years
The extended heat wave continues a streak of 11 consecutive months of record-setting temperatures. Read More
Fruits
September 15, 2016
California Growers May Face More Water C…
State proposal would divert more water to San Joaquin River system to save endangered fish habitat. Read More
Citrus
September 15, 2016
What The Bayer-Monsanto Merger Means Thu…
The deal, subject to regulatory approval, would create the world’s largest agriculture company. Read More
Citrus
September 14, 2016
Bayer Acquires Monsanto After Months Of …
Mega-Merger sealed with $66 billion all-cash transaction. Read More
Citrus
September 13, 2016
Can CRISPR Carry Agriculture Innovation …
Game-changing technology allows targeted gene modification to fight diseases like citrus greening. Read More
Citrus
September 7, 2016
Getting To The Root Of Improved Fruit An…
Taking a holistic approach to soil health is a key to increasing plant vigor and yields. High yields begin with Read More
Citrus
September 3, 2016
Farm Profitability Expected To Dip For T…
Net farm income could hit lowest figure since 2009. Read More
Citrus
August 30, 2016
USDA Offices Closed After Unspecified Th…
Agency locations in five states shuttered due to anonymous, but serious messages. Read More
Fruits
August 30, 2016
Farmworker Overtime Expansion Sent To Ca…
Allied industries say new regulation is burdensome when coupled with increase in minimum wage. Read More
Crop Protection
August 30, 2016
New Biopesticide Available From BioWorks
Mycoinsecticide has quick knockdown effect and multiple modes of action. 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
Citrus
August 18, 2016
Trump Campaign Announces Agricultural Ad…
Just three of the 64 are directly involved with fruits and vegetables, all three are Californians. Read More
Harvesting
August 16, 2016
Proper Stockpiling Can Maintain Almond Q…
As almond yields increase, growers may find themselves with more harvested crop than processors can handle. Proper stockpiling techniques can Read More
[gravityform id="62" title="false" description="false"]