The physiology of autumn remobilisation and senication’s role in shaping next year’s harvest
In the agronomy of perennial fruit and berry crops, there’s a fundamental rule that’s often overlooked once harvest is done: next year’s crop starts taking shape in the autumn of the current year. Once the fruit is picked, the plant’s life cycle doesn’t stop — it moves into a critically important phase of resource accumulation and redistribution, one that determines not just successful overwintering, but also the potential for flowering and fruiting the following season. Understanding the physiological mechanisms behind this process lets the agronomist actively manage orchard productivity using a tool such as senication.
A double timeline: next year’s crop is born in autumn
In perennial fruit crops, the formation of generative (flower) buds is a long, multi-stage process. Next year’s crop starts taking shape back in summer, running in parallel with the current fruit load, and isn’t complete until the following spring. There’s a clear phenological sequence to this: berry crops lay down their generative buds earliest, followed by stone fruit, with pome fruit doing so in July, August and September.
By the end of the growing season, the current season’s shoots already carry the rudiments of future inflorescences. But how far these develop, and whether they can deliver a full crop, depends directly on how well the plant is supplied with stored nutrients during autumn dormancy and early spring wake-up.
In early autumn, fruit plants’ nutrient demand rises again — this is when generative bud formation is finalised, and additional nutrient reserves are laid down in the tree’s tissues. These reserves become the “starting capital” the plant lives on in spring, before the root system ramps up active nutrient uptake from the soil.
The physiology of autumn outflow: remobilisation as a survival strategy
Once fruiting and harvest are over, the plant enters the remobilisation phase — a process in which nutrients accumulated in the vegetative organs (leaves, shoots) are actively transported into storage tissue: buds, wood and the root system. From a physiological standpoint, this is a natural mechanism for preparing for winter dormancy and spring regrowth.
Research on perennial fruit crops shows that nitrogen and carbon accumulate throughout the tree in autumn and are then sharply mobilised to fuel spring regrowth. The main storage form of nitrogen is amino acids, particularly arginine, which accumulate mainly in the roots. Most of the stored nitrogen remobilised into new organs in spring, however, is actually supplied by the trunk and shoots — up to 82.2% of the nitrogen that flows out of senescing leaves in autumn ends up stored in the trunk and shoots.
This process is critical to a successful start to spring growth. If the autumn outflow of nutrients into storage organs is incomplete, the plant enters spring with depleted reserves. Under those conditions, buds can wake up weak, flowering can be patchy, and fruit set can be prone to dropping. That’s exactly why sound management of autumn metabolism is the foundation for a “well-provisioned spring” and a strong crop the following year.
Senication as a tool for managing autumn outflow
Under natural conditions, remobilisation proceeds at whatever speed and completeness weather and the plant’s physiological state dictate. But agronomists have a tool available for actively driving this process: senication.
Senication (from the Latin senescere, “to age”) is a method for artificially accelerating the plant’s natural physiological ageing. Its purpose isn’t to dry down the green mass — it’s to optimise the outflow of nutrients from the leaves and stems into storage organs. Unlike desiccation, which is essentially harsh chemical drying, senication is a gentle, physiologically gradual process focused on the quality and completeness of reserve accumulation.
Applying senication in the post-harvest period serves the following goals:
Boosting assimilate outflow. Senication stimulants activate the enzymatic pathways of reutilisation, driving a more complete transfer of sugars and amino acids from the leaf canopy into the buds, wood and root system.
Building quality generative buds. Adequate reserve accumulation in bud tissue supports their full differentiation and a strong flowering potential the following season.
Raising winter hardiness. Plants that have built up an adequate reserve of carbohydrates and amino acids in their storage organs handle winter frosts and sharp temperature swings considerably better.
Securing a vigorous spring start. Nutrients stored in autumn become immediately available for use as buds wake up, supporting even flowering and vigorous growth.
Senication products: composition and mechanism of action
Various specialised products have been developed to implement a senication strategy in perennial crops. Their composition is balanced for the tasks of the autumn period.
These products work by stimulating the enzymatic pathways of reutilisation — the processes responsible for mobilising stored nutrients and converting them into transport forms. Senication agents boost the conversion of stored nutrients into plastic substances, speed up maturation, and drive the outflow of sugars and amino acids from the leaf canopy into the buds, wood and root system.
Application guidelines for perennial crops
For the best effect, senication in fruit crops is applied in the post-harvest period, before natural leaf fall begins.
The treatment is applied as a foliar spray, ensuring even coverage of the leaf surface. It’s important to carry out the treatment before the leaves begin yellowing naturally, while the plant’s transport systems are still fully functional and able to sustain an efficient outflow of assimilates.
Conclusion
Next year’s crop isn’t just a matter for spring — it’s the result of sound agronomic action in autumn. Post-harvest senication allows active management of the natural remobilisation processes, ensuring the most complete possible outflow of nutrients from the vegetative organs into storage tissue. The reserve built up this way becomes a reliable foundation for successful overwintering, even bud break in spring, and a strong crop ahead. Investing in autumn nutrition and managing physiological ageing is a direct contribution to the orchard’s productivity the following season.