Take Control of Your Fertility Program

Take Control of Your Fertility Program

Dylan Rogers, Sales Account Manager for AgroLiquid

Almonds in blossom
Almond tree blossom

The 2020 almond crop is upon us. Trees are beginning to break dormancy, soon full bloom will occur, and the honeybees will be busy pollinating what will be our highest yielding crop to date – we hope. There are many factors that will affect the yield potential of this year’s crop; some we can control and others we cannot. Mother Nature and the weather are out of our hands – all we can do is hope that it works in our favor. We can fight disease and insect pressure, but we cannot prevent it completely. One factor we do have complete control over, however, is our fertility program and ensuring we supply the trees with the nutrients they need to produce that high-yielding crop.

Soil Samples

A great starting point for building your seasonal fertility program is by assessing what you have in the soil. Looking at a current soil sample will give you an idea of what needs to be done in season to ensure adequate fertility for maximum yields. There are multiple things to consider when reading a soil test. You may see that most or all of your nutrient levels read adequate or high; However, the ratios of some nutrients are more important than the levels. For instance, iron and manganese are antagonistic to each other. You may have adequate levels of both nutrients in your soil, but if the ratio is off, you may see symptoms of deficiency. You need more iron than manganese in the soil. The ideal ratio is 2:1 iron to manganese. The closer this ratio gets to 1:1, the more likely you will see an iron deficiency in season. The ratio of phosphorus to zinc is also an important factor. A ratio of 10:1 phosphorus to zinc is the ideal balance between these two nutrients. If phosphorus levels get too high, it may induce a zinc deficiency. These are just two examples of many ratios that should be addressed in your soil. A soil sample will ensure you have the information you need to get off on the right foot to maximizing this season’s yield.

Bud Break, Pink Bud, Bloom

During the period in which fruit buds are swelling, the trees are also working below the soil surface. A new flush of feeder roots are pushing out, and having an adequate supply of phosphorus and soil moisture is critical in the development of these new roots. Choosing a phosphorus fertilizer that is protected from tie-up in the soil ensures the most return on this investment. Following bud swell and new root development will be bud break, a period in which flower and pollen development are crucial. These fruiting buds that will become flowers are the fate of this season’s crop, so we do everything possible to protect and ensure their viability. Foliar applications of phosphorus, calcium, zinc, boron, and molybdenum can be beneficial, as they play important roles in all aspects regarding pollen.

Fruit Development

 The tree’s highest demand for nitrogen and potassium is from fruit set to harvest. Supplying these two nutrients in adequate amounts is crucial to achieve a high yielding crop. Nitrogen is a critical component of many plant parts and functions. It is needed to produce chlorophyll, DNA and RNA, and to synthesize amino acids. Studies have shown that for every 1,000 pounds of kernels removed, about 85 pounds of nitrogen are removed after accounting for fertilizer inefficiencies. Choosing a nitrogen fertilizer that is low in salts and less likely to leach or volatilize will ensure optimum uptake by the tree and give you the most return on your fertilizer investment. Potassium is also very important for many plant functions and is required in large amounts. Potassium plays a major role in the opening and closing of stomata, photosynthesis, translocation of sugars, and many other plant processes. Studies show that for every 1,000 pounds of kernels removed, around 90 pounds of K20 are removed. There are some important things to take into consideration when choosing a potassium source. Almonds are very sensitive to salts such as chlorides and hydroxides. Some fertilizers can even be toxic if applied at higher rates. Choose a potassium source that is free of chlorides and hydroxides to ensure maximum uptake and to minimize potential for crop injury.

Taking control of your fertility program this season will help achieve maximum yield potential. Again, there are multiple factors that are out of our control so taking advantage of the factors we can control is important. Choose your fertilizers this season with plant and soil health in mind to maximize your return on investment.

Almond fields

The 12 days of Crop Nutrients

Day 4 

Since I have already lost the theme of this thread (being a tie with the beloved carol, The 12 Days of Christmas), I won’t try to draw a connection between four calling birds and potassium – although I’m sure I could if I tried hard enough.

 

Potassium in one of the primary plant nutrients. It is essential for the transport of sugars and the formation of starches and oils. Potassium helps to regulate the opening and closing of a leaf’s stoma which are important for the efficient use of water by the crop.

Potassium deficiency in almonds
Apple with a potassium deficiency
Potassium deficiency in grapes

 

 

 

 

 

 

Potassium also promotes root growth, increases a plant’s resistance to disease and cold temperatures. It improves the size and quality of fruits, nuts and grains, and is essential in high-quality forage. Crops that produce large amounts of carbohydrates (sugars) require large amounts of potassium – sometimes even more th an nitrogen! Cotton, almonds, alfalfa, grapes, cherries, and peaches are all especially fond of potassium.

 

Common symptoms of potassium deficiency:

  • Slow growth
  • Tip and marginal leaf burning
  • Burning of older leaves
  • Weak stems and stalks causing lodging
  • Low fruit sugar content and shriveled seeds
Corn with a potassium deficiency

The 12 days of Crop Nutrients

Day 3 

On to day three of crop our nutrients post. If you aren’t following along in our 12 Days of Crop Nutrients, be sure to check out day 1 – phosphorus, and day 2 – calcium. For our third day of crop nutrients, we’re going to discuss the micronutrient boron. It’s been said before, but it bears repeating: while crops needs less of a micronutrient, those nutrients are no less important to maximizing crop potential.

Boron deficiency in almonds

Boron (B)

Boron is necessary for cell division and differentiation. It helps maintain a balance between sugar and starch and aids in the movement of calcium. Boron is also essential for the germination of the pollen grains and pollen tubes in plants and has a direct effect on yield. No pollination, no crop. In other words, it may be a micronutrient, but it’s no less important to crop potential than nitrogen, phosphorus or potassium.

Cauliflower with boron deficiency

Boron is a nutrient that becomes immobile once it is utilized within a crop. Therefore, it is essential to have an available boron “pool” within the soil throughout the growing season. Some symptoms of boron deficiency can include:

  • Shortened plant nodes
  • Thickened, brittle and curled leaves
  • Terminal growth dies and / or young growth tissue deteriorates
  • Reduced flowering and fruit set, poor seed set

Malformed or small fruits and physiological disorders associated with root and tuber crops.

The 12 days of Crop Nutrients

Day 2

Welcome to our second day of the crop nutrients post. Hopefully you caught our first day – where we focused on phosphorus. In the traditional Christmas carol, the second day is two turtle doves. Since I don’t have any clever alliteration ideas for this one, I am going to talk about a secondary nutrient: calcium.

 

Calcium (Ca)

Calcium is a secondary plant nutrient that stimulates root and leaf development, activates several plant enzymes, and is required by nitrogen-fixing bacteria. In the soil, calcium indirectly influences yield by reducing soil acidity. It also helps improve root growth conditions, molybdenum availability, and uptake of other nutrients. In the soil, calcium indirectly influences yield by reducing soil acidity, which in turn lowers the solubility and toxicity of manganese, copper, and aluminum.

Alfalfa calcium deficiency comparison. (Left has deficiency, right does not)

Calcium is the third most important element in a plant. And, calcium is the fifth most abundant element on the planet. It makes sense that traditionally, growers don’t apply much calcium, because they assume the plant will get what they need from the soil. But, soil calcium is usually found in a form that is not easily taken up by plants.

 

Calcium deficiency in an apple

As an example, in an apple tree, the leaves, new shoots, and fruit all take calcium. The nutrient will be found in the tissues and the root, but the fruit cannot compete with the other parts of the plant. Hence why the fruit often doesn’t get enough calcium. That is why calcium deficiencies are evidenced on the fruit, rather than the rest of the tree. In apples, a calcium deficiency causes a disorder known as bitter pit. Bitter pit is a physiological breakdown of the cell walls in the fruit that occur below the skin of the fruit. For that reason, when scouting for calcium deficiencies in fruit trees, it is important to test the fruit, rather than relying solely on leaf or soil tests. Signs of calcium deficiency common in all crops include abnormal dark green foliage, premature shedding of blossoms and buds, and weakened stems.

 

Further problems with the calcium levels in the plant, and therefore in the fruit, are often caused by changes in the weather. In high temperature, low humidity conditions, for example, transpiration will increase dramatically, causing the plant to use more water. In irrigated crops, if watering has not been well scheduled, even soils with good levels of calcium can have problems in the fruit caused by calcium deficiency, such as blossom-end rot in tomatoes. This is the time when we need a fast calcium fertilizer that can be applied by foliar.

 

Common symptoms of calcium deficiency:

  • Death of growing points
  • Abnormal dark green foliage
    Example of calcium deficiency in lettuce
  • Premature shedding of blossoms and buds
  • Weakened stems
  • Tip burn of young leaves (primarily in vegetable crops)
    Calcium deficiency in corn
  • Water soaked, discolored areas on fruits
    Canola with a calcium deficiency

The 12 days of Crop Nutrients

Is anyone else missing the Christmas carols? Because we’re in the midst of the 12 Days of Christmas, and because the lack of seasonal music has me feeling a little deflated, I’m going to borrow the theme of the beloved Christmas carol “The 12 Days of Christmas,” and turn it into the 12 days of crop nutrients.

Partridge in a Pear Tree – or Phosphorus (P)

The alliteration here demands that we feature phosphorus first.

Phosphorus is an essential plant nutrient and very important for numerous plant processes and crop production. It is a vital component of DNA and RNA, the building blocks of proteins and protein synthesis. The adenosine triphosphate molecule (ATP) molecule is responsible for storing and transferring all of the energy produced and needed by the plant. At the core of this ATP molecule are phosphates, responsible for all of the activity of ATP. Phosphorus also plays a major role in the stimulation of new root growth.

So, P is Important

Our crops clearly need phosphorus to thrive. So, what do we need to worry about when supplying P? “Tie up” within the soil is the primary concern with phosphorus fertilizers. In acidic soil conditions, P will tend to get tied up by iron, aluminum, and manganese. In basic soil conditions, calcium will be the major component of phosphorus tie up.

Phosphorus deficiency symptoms in corn
Phosphorus deficiency in corn

Phosphorus is most available to the plant in a soil pH range of 6.3-6.8. Common liquid fertilizers, such as ammonium polyphosphate (10-34-0) and orthophosphate (9-18-9), applied in the early spring will also have a likely chance of being tied up if a gypsum application was made in the fall.

Choosing a phosphorus fertilizer that is protected from tie up will ensure that you get the most out of your fertilizer investment and that your crop will receive the required amount of phosphorus needed.

Available P versus Usable P

Not to mention, applying phosphorus as a crop nutrient can be tricky. Just because phosphorus was applied to the soil does not mean that it is doing what you want it to do: feed the plant!  AgroLiquid founder, Douglas Cook, was known to say that all applied fertilizer is available, but not all applied fertilizer is usable. Sounds funny, but it’s true. What’s the difference? All fertilizer is available to plants — it’s right there for the taking. But it may not be usable. In order for a nutrient to be usable, it must be close to the roots and it must be in a form that the plant can absorb.

Nutrients like nitrogen can be lost to leaching or volatility before absorption. Potassium can be strongly held by clay in the soil and not able to be taken up by roots since it is not in the soil solution. Phosphorus can also become unusable. Phosphate is negatively charged and can react with, or be fixed, by positively charged elements in the soil (cations). Plants cannot take up these compounds of calcium phosphate, aluminum phosphate or iron phosphate. Estimates are that the crop will utilize only around 20% of applied phosphate fertilizer during the season after application, and in following years, the amount becomes progressively less as it reverts to mineral forms. Again, the nutrients are there and available, but they are not always usable.

Out of Sight, Out of Mind

You cannot actually see the fate of phosphate molecules in the soil, so it’s not necessarily something growers are thinking about. If only a small percentage of your planted seed came up, you would probably be mad because you can see that loss. Similarly, only a small percentage of the applied phosphate is usable. However, you cannot see this, so it is not a concern.  But it should be.

Placement is Key

Phosphate fertilizer works best if it is placed close to the seed at planting. In the picture at the left, it is apparent that phosphate fertilizer placement is affecting growth. Five rows of the plot had 5 gal/A of Pro-Germinator applied through the planter, and the sixth row had no planter fertilizer.

Phosphorus source comparison in field corn
Fertilizer placement comparison using Pro-Germinator in corn

The rows with the In-furrow placement are tasseling, whereas the 2×2 placement has yet to tassel. Close inspection shows that the corn with the 2×2 placement is taller than the row with no fertilizer, but it is behind the rows with the in-furrow placement. This shows that phosphorus placement for earliest root access affects plant growth and yield. Additional testing at the North Central Research Station has shown that in furrow placement can out-yield 2×2 placement by almost 5 bu/A.

In order for phosphorus fertilizer to be most effective, it needs to be usable. Usability is increased by placement close to the seed row and protection from fixation losses. Pro-Germinator is the only fertilizer that does both.

 

 

 

Common phosphorus deficiency symptoms:

  • Stunted plants
  • Leaves may be darker green or begin purpling
  • Leaves may curl upward
  • Maturity can be delayed
  • Poor seed set
  • Poor fruit quality
Phosphorus deficiency in citrus fruit
Phosphorus deficiency in citrus fruit can result in poor fruit quality.
Purpling leaves, like those in this canola plant, can be a symptom of phosphorus deficiency
Purpling leaves, like those in this canola plant, can be a symptom of phosphorus deficiency

 

 

Building and Managing Soil Phosphorus

By: Dr. Jerry Wilhm, Senior Research Manager

Clearly, phosphorus is important for growing crops. It is involved in many functions within a plant like energy storage and transfer (ATP/ADP), protein synthesis, photosynthesis, nucleic acid (DNA/RNA) synthesis, nutrient movement through cell walls and many more processes. Therefore, it pays to make sure phosphorus does not become deficient in plants.

However, applying phosphorus as a crop nutrient can be tricky. Like all nutrients, phosphorus must be managed. In other words, just because phosphorus was applied to the soil does not mean that it is doing what you want it to do: feed the plant!  AgroLiquid founder, Douglas Cook, was known to say that all applied fertilizer is available, but not all applied fertilizer is usable. Sounds funny, but it’s true. What’s the difference? All fertilizer is available to plants — it’s right there for the taking. But it may not be usable.

In order for a nutrient to be usable, it must be close to the roots and it must be in a form that the plant can absorb. Nutrients like nitrogen can be lost to leaching or volatility before absorption. Potassium can be strongly held by clay in the soil and not able to be taken up by roots since it is not in the soil solution. Phosphorus too can become unusable. Phosphate is negatively charged and can react with, or be fixed, by positively charged elements in the soil (cations). Plants cannot take up these compounds of calcium phosphate, aluminum phosphate or iron phosphate. Estimates are that the crop will utilize only around 20% of applied phosphate fertilizer during the season after application, and in following years, the amount becomes progressively less as it reverts to mineral forms. Again, the nutrients are there and available, but they are not always usable.

This may not be a concern to growers because you cannot actually see the fate of phosphate molecules in the soil. If only a small percentage of your planted seed came up, you would probably be mad because you can see that loss. Similarly, only a small percentage of the applied phosphate is usable. However, you cannot see this, so it is not a concern.  But it should be.

 

 

 

 

Phosphate fertilizer works best if it is placed close to the seed at planting. In the picture at the left, it is apparent that phosphate fertilizer placement is affecting growth. Five rows of the plot had 5 gal/A of Pro-Germinator applied through the planter, and the sixth row had no planter fertilizer. The rows with the In-furrow placement are tasseling, whereas the 2×2 placement has yet to tassel. Close inspection shows that the corn with the 2×2 placement is taller than the row with no fertilizer, but it is behind the rows with the in-furrow placement. This shows that phosphorus placement for earliest root access affects plant growth and yield. Additional testing at the North Central Research Station has shown that in furrow placement can out-yield 2×2 placement by almost 5 bu/A.

Pro-Germinator has carbon encapsulation for protection against fixation losses that affect other forms of phosphate fertilizer. This is the  Flavonol Polymer Technology that AgroLiquid developed to prevent fixation losses and enable extended nutrient release into the growing season. This also increases crop safety and can be effective at lower rates than those of conventional fertilizer like 10-34-0. In this experiment from the North Central Research Station, the lower rate of Pro-Germinator enabled a higher corn yield than that with the higher rate of 10-34-0. Closer inspection shows larger ear size and the darker yellow corn indicates advanced maturity.

In order for phosphorus fertilizer to be most effective, it needs to be usable. Usability is increased by placement close to the seed row and protection from fixation losses. Pro-Germinator is the only fertilizer that does both.

 

Postharvest Fertility – Trees and Vines

By Dylan Rogers, Sales Account ManagerDylan Rogers, Sales Account Manager for Southern California

With almond and grape harvest underway here in California, it is easy to fall into the mindset that the finish line for yet another growing season is near. Unfortunately, that is not the case. In fact, the most important part of the growing season is still upon us. Postharvest irrigation and fertility can be the most crucial aspect of growing trees and vines. Growers, PCAs, and CCAs are always striving to increase yields and quality. Having a solid postharvest game plan plays a critical role in ensuring better yields and quality for next season’s crop.

After the stress of harvest, nitrogen, phosphorous, and potassium will begin to transition from leaves to spurs in almonds, and from leaves to roots and woody tissues in vines. In almonds, bud initiation and differentiation has already begun, so the fate of the 2020 crop is already underway. Water stress at this point in time will significantly reduce next year’s crop. Postharvest irrigation is also very important to ensure that the leaves stay active for as long as possible so they can continue photosynthesizing and storing much needed carbohydrates for next year’s crop. When dormancy breaks in early spring, trees and vines will be functioning solely on stored nutrients. Nutrient uptake from the soil is very minimal at this point due to cool soil temperatures as well as the lack of leaves. Adequate postharvest fertility to replenish nutrient reserves will ensure that your crop has the energy it needs to maximize production when dormancy breaks come spring.

Nitrogen (N)

Up to 20% of the total seasonal demand for nitrogen in almonds can be applied postharvest. This is also very similar for grapes. Postharvest nitrogen will help maintain leaf area and extend the time for photosynthesis to keep producing carbohydrates in the trees and vines. Postharvest N will also ensure that reserves are replenished and early shoot growth and leaf out will be strong in the spring. It is important to take in-season tissue samples into consideration when determining how much nitrogen to apply. Any soil-applied nitrogen in the nitrate form that is not taken up by the roots will be subject to leaching from rainfall and irrigations. Foliar-applied nitrogen is also a good choice for postharvest applications. It is common to use a fast acting nitrogen source in this situation, such as urea-based products.

Almonds ready for harvestPhosphorous (P)

The amount of phosphorous used by trees and vines is much less compared to the demand for nitrogen and potassium. However, this does not mean it is less important for optimal growth and yields. A postharvest application of phosphorous will promote healthy fall and spring root flushes, as well as ensure the trees and vines have a good energy source when dormancy breaks in the spring. Choosing a phosphorous fertilizer that is protected from tie up from cations in the soil is important and will ensure that it is free and available for the plant to uptake as needed.

Potassium (K)

Potassium demand in almonds and grapes is even higher than that of nitrogen. A postharvest application of potassium is essential in order to restore reserves, even more so if your yields were above average this season. Potassium is an important aspect in plant water relations and cell reproduction. If potassium reserves are deficient when dormancy breaks in the spring, new fruiting spurs will develop at a slower pace or even die prematurely as compared to a tree that has optimal potassium reserves. Root uptake is minimal at this point, so a soil application of potassium will serve to replenish K reserves in the soil. A postharvest foliar application of potassium is a great way to ensure you get the potassium into the trees and vines to replenish those reserves. Choosing a K product that is free of chlorides and hydroxides, as well as effective at penetrating the leaf cuticle and easily translocated once in the leaf will provide the greatest return on your fertilizer investment.

Zinc (Zn)

Zinc is a very important micronutrient that plays a major role in synthesizing auxins. These auxins ensure a uniform bud break and a good fruit set in the spring. Almonds are commonly zinc deficient. This is due to a number of reasons, including certain rootstocks that are not adequate at taking up zinc from the soil. Zinc deficiencies are also common in areas with alkaline soils. Zinc is fairly immobile in the soil so postharvest foliar applications are most effective at correcting deficiencies and restoring reserves.

Boron (B)

Collecting hull samples to send off for boron analysis should be a staple in your postharvest game plan. Hull samples are the most effective indicator of boron levels in almonds. Boron is very critical for development of flowers, specifically pollen development and viability. If the hull analysis shows less than 80 parts per million boron, the trees are deficient and are most likely losing yield potential. Postharvest foliar applications of boron are an effective way to correct deficiencies and restore boron levels in the tree.

As you complete this year’s harvest, let your mind shift gears and begin thinking about next year’s crop. Its fate is already underway and having a solid postharvest irrigation and fertility game plan will ensure your trees and vines go into dormancy with adequate nutrient reserves. With a good postharvest fertility program, your crop will be off to a great start come spring and you’ll be well on your way to improving yields and quality year after year.

Find a crop nutrition expert in your area to discuss your program.

California permanent crops

The Benefits of Soybean Foliar Fertilizer Application

John Leif, Field Agronomy Manager

The debate of the benefits of foliar fertilizer applications on soybeans has been ongoing for more than 20 years. Some of the benefits to foliar fertilizer applications include quick reaction to deficiency symptoms or low tissue analysis. Foliar feeding enables a bypass of soil issues [such as cold, infertile soil; nutrient fixation, drought; sodium, etc.] or insufficient root growth, which would cause soil-applied fertilizer to not be as readily absorbed. Foliar fertilizer has a relatively low cost, especially if nutrition is added to a foliar crop protection, such as fungicide, plant growth regulators, or herbicide application. It is also possible to target mid-season growth stages with specific nutrients.

Things To Consider

There are several things to consider when planning a foliar fertilizer program in soybeans. Nutrients must be taken in to the plant before the plant can utilize them, whether applied through the soil or as a foliar spray. When applied as a foliar spray, a nutrient must penetrate the leaf surface and be taken in to the leaf. Soybean leaves, as well as leaves of most plants, have a waxy layer at the surface known as the cuticle. The cuticle is present on the upper and lower sides of the leaf, but cuticle thickness is usually less on the underside of the leaf. The cuticle and related structures help protect the plant from extremes in temperature, humidity, and pest damage.

Leaves also have stomata, which regulate the exchange of carbon dioxide and water transpiration in the plant. Most of the stomata on soybean leaves are located on the lower side of the leaf. The absorption of nutrient solutions by the leaf surface may occur via the cuticle, cuticular cracks and imperfections, and the stomata.

The soybean plant is affected by a number of environmental conditions, and that can influence the effectiveness of the fertilizer application. Temperature and relative humidity have the most influence of any environmental conditions. Excessive heat and cold causes stomatal openings to close and restrict nutrient and water movement. Also, plant metabolism slows in these conditions, potentially limiting the ability of the plant to absorb and utilize nutrients. Therefore, it is important to apply foliar nutrition during optimal temperature ranges when plant photosynthesis and respiration are not inhibited. Ideal temperature range for corn and soybeans is 70-85° F.

High humidity delays the drying of spray droplets from application, giving the plant a longer time for optimal absorption. Stomata remain open for longer periods in higher humidity conditions. In dry, lower humidity regions, plants develop thicker waxy cuticles, which limit nutrient uptake through the leaf. Drought stress also can reduce the effectiveness of foliar fertilizer applications.

Application timing is a critical to the potential success of a foliar nutrient treatment.  It is important to match the nutrient application to the growth stage of the plant. For example, boron is an important nutrient for flowering and pod establishment in soybeans. A foliar application of boron should be applied no later than early flowering stages (R1 – R3) in order for the plant to benefit from that application. Nutrients such as potassium and manganese, however, are utilized by soybeans at many growth stages so the plant can benefit from a foliar treatment of those nutrients across a wider application window.

Minimize Yield Loss

Ideally, foliar nutrition should be a component of a complete crop nutrition program. However, foliar nutrition can be used to address nutrient deficiencies that are observed in the field. Early, accurate identification and treatment of nutrient deficiencies with foliar fertilizers will minimize the yield loss in that crop. It is generally understood that yield losses are possible when deficiency symptoms are visible and those losses cannot be reversed by foliar fertilizer, but the remaining yield potential can be protected with a foliar treatment.

Application techniques can also influence the success of a foliar fertilizer treatment. Complete coverage of the leaf area maximizes the stomata exposed to the nutrients for uptake. Small droplet sizes applied at high pressure allow the product to reach all plant surfaces. In some cases, surfactants can be used to improve droplet coverage as well.

Plant nutrients can be applied in combination with crop protection products. This saves on application costs and potential mechanical damage from driving through a field. It is important to read and follow the label(s) of all pesticides used in tank mix combination with crop nutrients.

Fertilizer product quality plays an important role in the effectiveness of a foliar nutrient application. Some fertilizer products are very effective as soil applied products but are not effective as foliar sprays. Certain nutrients, especially nitrogen and sulfur, can cause leaf burn and other crop damage if a product not designed for foliar application is used. It is also important to make sure water-soluble granular fertilizers are well mixed in the spray tank to provide adequate nutrition and avoid filter or nozzle plugging.

Minimize Risk

AgroLiquid’s Flavonol Polymer Technology™ makes many of our products effective when applied as foliar sprays. This technology utilizes naturally derived sources that are quickly broken down by plants and used as metabolites in foliar applications, making the nutrients available for the plant to uptake. Many AgroLiquid fertilizer products have been designed to be safe for foliar applications in soybeans, minimizing the risk of crop injury and improving the availability of those nutrients in the plant.

With higher yield goals, foliar feeding may provide optimal results. Timely applications of nutrients can help rectify some nutrient deficiencies, but more important, foliar applications can provide necessary nutrients at times of high demand for plants.

Using Almond Tree Fertilizer to Restore Potassium

almond tree fertilizer to prevent potassium deficiency

For every 1,000 pounds of almond kernels harvested, around 80 pounds of potassium (as K2O5) leaves the soil. This places enormous nutrient demands on the soil, year after year. Without additional nutrients, potassium deficiency can quickly affect yield and the health of the almond grove. However, many almond tree potassium fertilizer products also damage the health of the soil by leaving residual salts and chlorides while tying up nutrients. It is possible to restore potassium in the soil and even correct potassium deficiencies throughout the year using an agile almond tree fertilizer that is easy to apply.

Almond Tree Fertilizer Restoring Potassium Without Soil Damage

How Much Potassium is Available to My Almond Trees?

almond treeAlthough most soils contain large amounts of potassium, relatively small amounts of it are in a form plants can use. Consequently, growers should base management decisions on how much potassium is available when the plants need it, rather than on how much potassium is available in the soil.

Each almond orchard is a unique environment, and different soil types hold varying amounts of potassium and release it differently. This can make it tricky to manage K effectively.

“Growers who want to maximize yields need to stay on top of their K applications,” says David Doll, University of California Cooperative Extension nut pomology farm advisor for Merced County. “Otherwise, deficiencies will reduce return bloom and decrease spur longevity, which affects yields over time.”

Potassium uptake in almonds is linear, with as much as 70 to 80% of total uptake complete by mid-June. This means continuous potassium supplements will support the almond tree’s growth throughout the growing season, stimulating the growth of fruiting wood, more buds, and improved harvests. Different soil types present different challenges for maintaining potassium levels. Sandy soils and sandy loams cannot retain potassium as well as others, and require smaller, more frequent almond tree fertilizer applications. Heavier soils like clay hold on to nutrients longer, and don’t need as many applications.

Do My Almond Trees Have a Potassium Deficiency?

potassium deficiency in almonds
Leaf curling, scorching and discoloration at the margins is a sign of potassium deficiency in almonds.

Deficiencies develop gradually over time and visual symptoms can take years before they show up. Plants lacking in potassium often show delayed or stunted growth. Other deficiency signs include inward curling of leaves, discolored leaf tips and marginal scorching. When severe, potassium deficiencies can increase the loss of fruiting wood, which results in reduced crop loads.

Continued monitoring and fertilization in the orchard helps growers build and maintain K at levels where deficiencies are less of a concern. Regular soil testing can help almond growers identify nutrient trends over time. Additionally, annual leaf samples help growers keep track of K levels.

“Mid-July leaf samples work well because tissue levels are relatively stable at that time of year,” says Doll. “Take two to three leaves from five non-fruiting spurs for at least 15 to 20 trees across the block. Trees should be 100 feet apart. To maintain sufficient levels across the orchard, UC Davis recommends shooting for a target potassium level of 1.6 to 1.8 percent.

Flexible Application Methods for Almond Tree Fertilizers

irrigation system watering treesMaintaining optimal potassium levels for almonds requires almond tree fertilizer treatments at harvest and throughout the year. Almond tree fertilizers with multiple application options give growers the flexibility to accomplish this.

AgroLiquid fertilizers can be applied in many different ways. They can even be used in combination with each other or with other crop protection products, so they can be quickly and easily applied.

With the ability to mix our almond tree fertilizer with other crop protection products, you reduce the time and energy needed to feed your trees. This way, you can grow more almonds with larger size and higher quality, without adding extra tasks.

Almond Tree Fertilizer Products to Maintain Potassium and Soil Health

AgroLiquid has formulated high-efficiency liquid fertilizer for almonds to sustain the almond tree’s linear use of potassium throughout the season. Unlike other almond tree fertilizers, ours is chloride- and hydroxide-free, so it supports soil health, long-term sustainability, and won’t upset the soil’s salt index.

sure-KSure-K is a chloride- and hydroxide-free potassium fertilizer ideal for supporting orchards with high potassium requirements, like almonds. With a neutral pH, Sure-K helps to protect the health and longevity of the soil, while supplying essential potassium. It can be applied as a topdress, sidedress, foliar, or through fertigation, and it can be used with many crop protection products.

kalibrateKalibrate is similar to Sure-K, but supplies sulfur in addition to potassium. Similar to Sure-K, Kalibrate is chloride- and hydroxide-free, and it can be applied in a variety of ways. Kalibrate is ideal as an early-season potassium fertilizer to stimulate strong initial growth and production.

 

PRG logoPrG provides a full array of macronutrients, including nitrogen, phosphorus and potassium, as well as iron. PrG is ideal for trees that have not yet reached maturity. PrG is also ideal for stimulating growth and speeding up reproduction at the start of the season.

 

Let Us Design an Almond Tree Fertilizer Plan for You

The ideal AgroLiquid almond fertilizer plan is dependent on your location, climate, soil conditions, and goals with your crop. All of our fertilizer programs begin with a review of your soil samples and consultation with one of our expert agronomists. After our analysis, our team will provide you with a couple options that will help you meet your goals on a budget that won’t break the bank. Talk to an agronomist to get started.

Kentucky Corn Looking Great with AgroLiquid

So last week, Senior Sales Manager Galynn, SAM Rob and I went down to Hopkinsville, KY to visit the Security Seed & Chemical Research Farm.  It is a large facility where fertilizer plots are established each year to test different program, both old and new.  Fertilizer Agronomist Lang French met us at the plots to show us around.  AgroLiquid has been a standard program there for quite a few years now.  But that is challenged each year.  They do have really good looking corn down there.

inspecting corn

 The corn is in the silking stage now.  Here is a plot that received a preplant application of dry fertilizer (9-23-30).

corn in silking stage

 And right next to it is a plot that instead received a planter application of Pro-Germinator + Micro 500.  Notice that the silks are turning brown indicating that it is farther along in maturity.

corn silk turning brown

Lang said that they often see tassel emergence at least seven days earlier with AgroLiquid compared to dry treatments.  One of the many features explaining the high performance of AgroLiquid.  Go to their upcoming field day if you are in the neighborhood.

And if you want to see a video discussion of these plots (and who doesn’t?) go to @DrJerryCropDoc on Facebook.