Shelf Life Starts at Fruit Set

Yara Crop Nutrition Sales Agronomist – Southern Queensland, Adam Kirk, says avocados need a regular source of nutrients, including nitrogen, calcium and boron, to maintain cellular integrity.

“Nitrogen has a direct influence on growth and yield,” he said.

“Applications must be carefully managed to prevent excessive vegetative growth at the expense of fruiting.

“Calcium plays an important role in cell structure and strength, which increases resilience to pressure from insects or disease, such as phytophthora root rot.

“Calcium is attracting growing attention from researchers and growers, not only to improve fruit quality, but as a means of improving storage and shelf life.

“Insufficient calcium leads to weaker cell walls and cell collapse.

“Boron is another common deficiency and multiple light applications throughout the year, particularly at flowering, help to improve the cellular integrity of plants and the efficiency of calcium application.

“High levels of calcium can increase tissue stiffness and the risk of cracking, whereas boron counteracts this by increasing tissue elasticity.”

YaraLiva calcium nitrate fertilisers deliver a rich source of fast-acting, plant-available nitrogen for fast uptake and soluble sources of calcium and boron for improved cell wall strength.

“Trees respond more quickly to nitrate than urea-based fertilisers,” Adam said.

“Nitrate is immediately available to the crop and is more mobile in the soil.

“Calcium nitrate is the most soluble form of calcium, making it immediately available for plant uptake.”

YaraLiva TROPICOTE (15.5% N + 18.8% Ca) and YaraLiva NITRABOR (15.5% N + 18.3% Ca + 0.3% B) are quality granular formulations suitable for field application.

The free-flowing, evenly-sized granules feature a unique coating technology to prevent moisture absorption during storage and handling, yet dissolve readily once in contact with moisture soil, humid conditions or night dew.
YaraLiva CALCINIT (15.5% N + 19% Ca) and YaraLiva CALCINIT B (15.5% N + 18.6% Ca + 0.1% B) are hydroponic grade water soluble calcium nitrate products. They are to be applied in the A tank in an A and B tank fertigation system or injected separately when fertigating a field crop.

Adam said a comprehensive crop nutrition program using quality fertilisers delivered important benefits right across the food chain.

“The use of quality YaraLiva calcium nitrate fertilisers improve fruit size, quality and marketable yield,” he says.

“Produce remains fresher for longer, thereby increasing shelf life.


“In turn, this delivers fresher, tastier and more nutritious fruit and vegetables to consumer.”

The use of YaraLiva fertilisers also offers important environmental benefits.

“Yara’s abatement technology produces almost 70% less greenhouse gas emissions during manufacture than nitrates produced in China using coal-powered energy sources,” Adam says.

“Likewise, nitrate fertilisers are intrinsically more efficient than ammonia fertilisers because the nitrogen content is already in a plant-available form.

“By comparison, the nitrogen in urea needs to be converted to ammonium and then into nitrate before it becomes available to the plants.

“Ammonium locks onto clay minerals and becomes immobile, meaning the plant roots have to grow actively towards the nutrient.

“All told, it is estimated that 20% of the nitrogen in ammonia is volatised before it can be utilised by the plant.

“This compares to just 0.7% for calcium nitrate fertilsers.”

Research shows that nitrates produces more yield per unit of nitrogen than UAN and urea.