Ask what cuts sugar production — not which bag to add

A plant is a solar factory. Light becomes sugars; sugars become leaves, roots, fruit, and seed. When yield is low, photosynthesis is weak, the growing window shortened, or resources are wasted.

The usual thieves: water stress that closes the leaf pores, heat that spoils set, missing nitrogen or magnesium in the green machinery, chewed or shaded leaves, and roots that cannot supply the factory.

Feed and water still matter. They are tools for the factory, not a substitute for light and green area. Other series cover soil tests and biology.

If bags rise and yield does not, the factory — not the label — is the question.

In this series

• Ask what cuts sugar production — not which bag to add
• A crop is only as good as its root system
• Maximise yield per drop, not drops per hectare
• Yield falls before the leaf wilts
• Fruit drop is the plant aborting when resources fail
• Architecture: every productive leaf needs light