Horn silica (501) for plant vitality & resilience
The contribution, measured
Time horizon: 1 season
How it contributes
It is the preparation used to reinforce light metabolism and photosynthesis, supporting ripening and canopy health.
What to measure for this pairing
Why this goal matters
Biodynamics seeks balanced, resilient vines through the silica preparations, medicinal plants (horsetail, nettle) and calendar work. The aim is a vine that ripens well and better withstands stress and disease.
Resilience comes mostly from the system as a whole — living soil, vigour balance, biodiversity — complemented by the preparations. Documenting the programme lets you assess the effect over seasons.
Goal indicators
Market & certification: Plant resilience underpins the reduction in interventions that biodynamics values.
How to apply the practice
- 1Dynamise in water for an hour at dawn.
- 2Spray as a fine mist over the canopy early in the morning.
- 3Apply sparingly, on fruit/flower days.
- 4Log rate, plot and date.
Frequently asked
Can 501 cause sunburn?
Applied in excess or in intense heat, the boost in light activity can worsen stress. That is why it is applied sparingly and early in the morning.
When is 501 applied?
Mostly in the ripening phase, early in the morning and on fruit/flower days, to support photosynthesis and fruit definition.
Same practice, other goals
Same goal, other practices — Plant
How GrapeFlow helps
The proof Demeter certification demands — logged by plot and date.
Biodynamic calendar
Root, leaf, flower and fruit days and the lunar phases in GrapeFlow, to plan preparation applications and work in step with the calendar.
Preparations & application log
Every application of 500, 501 and the other preparations logged by plot, date and rate — the history the Demeter audit asks for.
Tasting notes & analyses
Per-lot tastings and analyses over time, to relate the biodynamic programme to how the wine evolves.