Avocado Fertilizer Recommendations

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Our Recommendations for Avocado

• Lono – Yield

  Lono is Levity’s pioneering nitrogen fertilizer. Lono ensures that the nitrogen supplied is focussed on growing fruit rather than vegetation, it does this by supplying the nitrogen in ‘stabilized amine’ form which improves yield, photosynthesis, and root & fruit growth.

• Albina – Shelf Life

  Albina is a pioneering new calcium fertilizer that can reduce physiological disorders, improve flower set & fruit holding, and increase firmness and shelf life in avocado crops. Albina uses LoCal technology to help fruit absorb calcium, a nutrient that can improve quality but is poorly absorbed by developing fruits.

• Indra – Protect

  Indra helps avocado crops cope with stress caused by heat, cold, salinity, drought and high UV light. By protecting the avocado crop against these we are able to keep high yields & quality through unfavourable conditions.

• Damu – Bulk

  Damu helps avocado plants use their energy to bulk up the fruit rather than force late season leaf growth. It works by directing the flow of photosynthates in leaves towards the avocado fruit and roots, resulting in larger fruit.

Use Lono to Increase Yield & Prevent Alternate Year Yield Bearing

What is alternate year bearing?

Alternate Bearing is the tendency of avocado trees to have a year of high yield and Small avocados, followed by a year of low yield with larger avocados. This is a widespread and common problem amongst avocado and other fruit tree growers.

Why does alternate year yield bearing happen to avocado trees?

Avocado trees grow three crops at the same time: this year’s crop, flowers for the next crop, and budwood for the crop after that. To get consistent yields across all years the avocado tree must focus its growth equally on fruit (for this year), flowers (for next year), and shoots (vegetative growth).

Alternate Year Yield Bearing happens in avocado trees when the crop allocates too much resource on either the fruit, flowers or shoots (vegetative growth) and does not grow them all equally. By the tree focussing too much growth on fruit this year, it can have detrimental effects on the growth of flowers which affects the yield for next year.

Alternate Year Yield Bearing rarely occurs in nature, this asymmetrical growth between fruits, flowers and shoots is a consequence of the level and ‘form’ of Nitrogen we apply to crops.

Nitrogen taken up in ‘nitrate’ form is processed in leaves and causes the production of the growth hormone ‘auxin’, which emphasises vegetative growth. We see increased internode length, faster/uneven shoot growth and increased water shoot development & height (The Nitrate Effect).

Whereas nitrogen taken up in ‘amine’ form is processed in the roots and causes production of the growth hormone ‘cytokinin’, this emphasises fruit and flower development, root growth, shorter internodes and uniform shoot growth.

However, even when farmers apply nitrogen fertilizer in ‘amine’ form, the avocado crop is largely outcompeted for the amine nitrogen. The competing microorganisms convert the amine into ‘nitrate’, and consequently, even when farmers apply Nitrogen fertilizer in ‘amine’ form, the form of nitrogen taken up by the avocado crop is still ‘nitrate’ and therefore still favours heavy vegetative growth.

This means that the more nitrogen we feed the avocado crop, the more vegetative and unbalanced growth we get. When we consider this over several years, we see a ‘boom and bust’ cycle. This also results in most of the nitrogen we apply being pruned off each year, losing potential yield and wasting fertilizer input.

Our Solution

Lono

Our fertilizer Lono is formulated with our LimiN technology which supplies ‘Stabilized Anime Nitrogen’ to the avocado crop. Stabilized amine nitrogen supplies amine nitrogen to the crop in a way unrecognisable to microorganisms, and therefore the amine remains in amine form rather than being converted to nitrate. This means that the crop takes up most of its nitrogen in ‘amine’ form and therefore emphasises fruit and flower development and shorter internodes.

Using Lono to fertilize avocado crops alongside conventional nitrogen fertilizers helps the crop to allocate growth evenly between vegetative and reproductive (fruit & flowers) development.

Recommendations

Apply Lono throughout the season at 5L per Ha monthly by drip or foliar spray.

Use Albina to Improve Avocado Quality & Shelf Life

Calcium is a key nutrient in determining yield in avocado, as blossom end rot (main cause is Calcium deficiency) can result in losses from unmarketable fruit. Fruit firmness and flesh rigidity, both important for shelf-life, are also improved if calcium levels are high.

However, avocado farmers often get erratic results from calcium fertilizers. In this section we will discuss why this happens and how Albina overcomes the problem by allowing avocado fruit to absorb the calcium applied throughout the entire season.

Why calcium fertilizers give erratic results?

Calcium’s main role in avocadoes is to give cell walls strength and rigidity. Symptoms of deficiency include disintegration of cell walls and affected tissue collapse which causes cell walls to collapse. However, these problems occur due to localised deficiencies, this is why the symptoms of calcium deficiency such as internal blossom end rot usually affect fruits even when calcium levels in the leaves are good.

Avocado fruits calcium deficiency is not dictated by the amount of calcium applied or taken up, but rather, the fruits ability to transport and absorb calcium. This is why deficiencies occur even when conventional calcium fertilizers have been applied.

Let’s look at both calcium transport and calcium absorption in avocadoes to better understand what we can do to improve calcium levels.

Absorption of calcium is linked to presence of the auxin hormone. Tissues high in auxin absorb calcium easily, but tissues low in auxin have difficulty absorbing calcium no matter how much is available. This makes absorption of calcium rather than availability of calcium the main driver in Avocado fruits physiological disorders and shelf-life problems.

When we look at the physiology of the fruit, we can learn a little about best timings for reducing physiological disorders incidence. Auxin levels are highest in fruits between flowering and when the fruit is 5mm in size, this is the main period of cell division (which is powered by auxins).

As the fruit gets bigger it is focused on increasing the size of cells rather than creating cells, and auxin levels drop making it progressively harder to get calcium into fruit as it increases in size.

Given the physiology of avocados the best way to reduce blossom end rot is to focus on timing, placement and absorption rather than quantity and frequency of application.

Our Solution

Levity’s Albina fertilizer which uses LoCal Technology was designed with this in mind. LoCal technology enables the avocado fruit (naturally low in auxin) to absorb calcium in the absence of auxins. This means that Albina stimulates calcium transport into ripening fruit where conventional fertilizers cannot. Due to this efficiency, it is possible to get impressive results with very little input, because no excess calcium is applied and wasted.

Use Indra & Damu to Protect & Bulk

Boron is a difficult nutrient to get right, different crops have different ways of transporting and metabolising the nutrient. Avocado trees are even more difficult than most because they produce two types of sugars; one of which transports boron and the other does not.

To understand why the application of boron fertilizers can give ‘hit and miss’ results on avocado we need to understand:

1. How transpiration effects boron transport.
2. How photosynthesis effects boron transport.

Transpiration

Boron is transported from the roots and upwards through the plant as ‘boric acid’. Which is not phloem mobile. So, the plant uses the xylem to move the boric acid upwards via the transpiration stream. The foliage receives most of the boron, and here the outer canopy receives the majority of the nutrient, this is where the crop receives the most sunlight.

Consequently, anything which limits water transpiration from the avocado crop will negatively affect boron uptake. For instance, heat and salinity stress cause the crop to restrict water loss through transpiration by closing stomata, this therefore restricts boron uptake. So, agronomic practises and the weather have a larger effect on boron uptake than the level of boron supplied through fertilizer.

High temperatures, salinity stress, heat stress and drought all reduce transpiration, and therefore the avocado crops ability to move boron from the roots to the leaf. Preventing stress to our avocado crop is imperative to keep the supply of boron high.

Photosynthesis

Once the boron is in the in the foliage it is redistributed to fruits and flowers.

Avocado crops produce two kinds of sugars when they photosynthesise; simple C6 sugars (glucose, stored as starch in the fruit), and complex C7 sugars (D-mannoheptulose – transported as ‘perseitol’).

Avocado plants use perseitol to translocate boron into the fruits and flowers. Therefore, if the plant reduces the production of C7 sugars then supply of boron to the fruit and flowers lowers.

Growing conditions often effect the plants ability to photosynthesis and produce C6 & C7 sugars. For instance, if the avocado crop is subjected to an area of low light, then it will produce more C6 sugars and less C7 sugars, and therefore, less boron is supplied to the fruit and flowers.

If the foliage is producing a low level of perseitol, then boron supply to the fruits and flowers will be restricted regardless of how much boron is applied to the plant.

Our Solutions

Indra

Indra is our avocado fertilizer which improves both transpiration and photosynthesis during stressful conditions. Indra stimulates antioxidant production to protect the crop against stress.

Maintaining normal transpiration during stressful growing conditions allows boron to continue to be transported up to the foliage to be ready for translocation into the fruit and flowers. Maintaining normal photosynthesis during stressful growing conditions is important as it allows the avocado crop to produce the C7 sugars required to translocate the boron from the foliage to the fruit and flowers.

Damu

Damu is our innovative boron fertilizer which helps avocado crops translocate more boron into the fruit and flowers. Damu combines boron with stimulants to increase uptake speed and phloem loading, this allows small applications of Damu to be more effective than larger applications of other conventional boron products.

Foliar applied Damu improves avocado fruit and flower development & retention. It helps avocado crops grown in shade to maintain better boron transport from foliage to fruit and flower.

Summary

By using both Indra and Damu, farmers are able increase yields in favourable conditions and also maintain high yields during stressful weather conditions and agronomic systems which conventional products are less effective in.

Indra – use monthly during stress periods at 1 litre per Ha (1 pint per acre), can be applied foliar or through irrigation systems.

Damu – use during fruit and flower development periods every 4- 6 weeks applied foliar at 2 litres per Ha. Use adequate water for good coverage.