Virtually all cells, tissues and organs in plants age and senesce.

Kendon Chemicals general manager Chris Story says senescence is actually regarded as an evolutionary acquired process which is critical for plant fitness.

And Mr Story says understanding its detailed molecular nature is not only fundamental but also pivotal for improvement of crop yield, nutritional density and post-harvest storage.

He says impressive progress has been made in recent years in revealing molecular regulatory mechanisms, which were previously unknown.

Senescence is the last stage of a developmental program in the plant and occurs in a co-ordinated way via enzymes and growth regulators.

“During senescence, leaf cells are subject to massive physiological and biochemical changes including a dramatic transition from anabolism to catabolism resulting in nutrient redistribution to newly developing organs (i.e. next year’s crop),” Mr Story says.

“Many growers we talk to tell us they’ve sprayed the calcium and boron mix once or twice and assume the tree is ready for the coming spring growth,” he says.

“However, a supply of all the trace elements is still crucial at this stage and cannot be underestimated.

“Research by John Kempf in the US, and other horticultural areas around the world, suggests most crops achieve less than 50 per cent of their potential genetic growth.

“At Kendon we believe you can improve the potential of the trees for the next season by using a post-harvest-pre-senescence foliar spray containing EDTA trace elements and definitely no nitrate at this stage.”

Mr Story says it is critical to spray before senescence, and while the leaves are still using the chlorophyll in the biochemistry within their leaves.

He adds the sugars and other metabolites produced at this stage of the life cycle of the tree all go the embryos for next year’s fruit and to the roots and out to the soil to the micro-flora that will play such a big role in the health of the tree in the next season.

“Now is the time to act, while the leaves are still green, meaning the chloroplasts will still be making chlorophyl or energy for the tree,” Mr Story says.

“For energy and nutrient production, and to redistribute those nutrients in the pre-senescence part of the cycle prior to falling, the leaves still need all the trace elements they required during the growth phase,” he explains.

“This is really important. Kendon High K Foliar contains all those EDTA trace elements required for this part of the life cycle.

“We recommend two sprays alternated with the calcium/boron mix.

“Remember that pre-senescence is the time the tree is setting up next year’s crop and this is an exciting time to nurture your trees and to improve yield and quality and to allow your trees to achieve their genetic potential.”

Mr Story says farmers and horticulturalists are an interesting group in society in that they have to continually think at least a year, and mostly two years – or seasons – ahead of the general public.

To overcome this limitation, farmers must prioritise proper fertilisation practices.

Every farmer aims to maximise yield and nutrient density, minimise pesticide usage and achieve visible crop quality.

Foliar fertilisers (fertilising the leaf) using EDTA chelated trace elements offer numerous advantages making them an excellent choice for growers:

• fertilising made simple -for all fruit and vegetable crops for all growing stages except at blossom time.
• quick nutrient absorption - nutrients, including trace elements, are rapidly absorbed by plants through their leaves and roots. With foliar fertilisers, some nutrients can reach the plant’s root system within an hour of application.
• leaf energy production - leaves act as mini solar panels, producing energy through photosynthesis. By optimising leaf health and energy production, crops can experience increased yield and quality.
• increased vigour - boosted nutrient density, better appearance of produce, improved storage quality.