In Biodynamic Wine, Monty Waldin explains concisely and clearly the theory behind biodynamics and gives detailed instructions on making and using biodynamic preparations. The founder of biodynamics, Rudolf Steiner, created nine biodynamic preparations from natural substances – cow manure, quartz and seven medicinal plants. The extract below gives a brief introduction to two of these, horn manure 500 and horn silica 501, and explains the benefits of using them in growing wine grapes.

For a long, healthy life, a vine’s requirements are similar to those of a house: deep foundations, a roof that withstands the elements and strong supporting walls in between. The three biodynamic field sprays – horn manure 500, horn silica 501 and common horsetail 508 – assist in providing those metaphorical needs. The horn manure 500 soil spray allows strong foundations to form via a strong and complex root system. The horn silica 501 atmosphere spray encourages strong and vertically erect fruiting wood.

Horn manure 500, or the horn dung or cow dung preparation as some call it, is the one preparation that those with only a passing interest in or awareness of biodynamics seem to have heard of. Horn manure may even be considered the nursery-slope biodynamic preparation, because having mastered how to make it – bury a cow horn filled with cow manure for six months over winter then dig it up and extract the manure from the horn – and understood why it is used and how it is used in the way that it is, the rest of biodynamic theory and practice no longer seems quite so impenetrable.

From a biodynamic perspective, manure is not simply vegetable matter that has broken down whilst passing through an animal’s digestive system but vegetable matter which has also been impregnated with an animal’s metabolic forces. Digestion releases energy as both intangible forces and tangible substances to nourish both the spiritual and physical body. Steiner said that by burying the manure in the horn the life (etheric) and soul (astral) forces already present in the manure can be further enlivened by the presence of the surrounding earth. Doing this in winter is quite deliberate. Winter is when the earth recharges itself on a substance level – think about all the potential for growth, visible only in summer, stored underground during winter in roots or seeds. Winter is also the moment when the earth recharges itself on a forces level by breathing in life-giving formative forces from the cosmic environment, which Steiner said play a formative role in shaping all living things. Horn manure 500 is not fertilizer per se but provides a highly concentrated, life-giving, fertilizing force. It contains unusually high levels of enzymes, organisms which act like a living oil for the biological wheels of life. When you think of manure horns lying underground you can imagine them as being like giant worm castings whose role is soil rejuvenation.

Horn silica 501, or horn quartz (horn silicum) as it is sometimes known, is the yin to horn manure’s yang. While horn manure 500 influences the lower part of the vine and its roots, horn silica 501 influences the upper part of the vine, namely its shoots, leaves and the wine grapes. Whilst horn manure 500 is sent to work when the afternoon sun is approaching the yardarm and sprayed in thick drops on the dark and heavily tangible earth to pull vine roots downwards, horn silica 501 is mistily wafted into the bright intangible atmosphere to yank the vine shoots upwards as the morning cockerels are clearing their collective throats. Steiner said that horn silica 501 complements and supports the influence coming from the soil as a result of the horn manure 500. Horn silica thus represents a concentration of the forces within sunlight. Horn manure 500 mobilizes matter in the plant which horn silica 501 forms and sculpts, working on the internal structure of plants, favouring their uprightness or verticality (more visibly erect vine shoots) and strengthening the outer cell walls (epidermis) of vine leaves and grapes. If horn manure 500 drives into wine a sense of place or terroir, the horn silica 501 ensures this sense of place tastes ripe.

It is tempting for biodynamic farmers in general and winegrowers in particular to focus overly on horn manure 500 at the expense of horn silica 501. There may be three reasons for this. The first is that because the organic movement has hammered into farmers the importance of soil health, horn manure 500 is seen as the all-in-one restorative for soils whose mineral balance and microflora have been adversely affected by conventional modern farming techniques. Second, spraying soil with a brownish-coloured ‘liquid manure’ which horn manure 500 can appear to resemble seems to make more sense to farmers than spraying what resembles glorified water over crops; after all, the contents of a bucket of stirred water and one containing horn silica 501 look essentially the same. Finally, winegrowers – nervy folks who generally get to make wine at most fifty occasions a lifetime – can’t always see why attracting warmth forces into their vineyards, which are invariably located in hot and especially sunny places anyway, is really necessary.

For winegrowers, horn silica 501 produces vines with more upright and less floppy shoot growth, shoots and leaves which show greater photosynthetic activity, healthier vines in general and grapes with riper flavours, balanced (meaning lower) sugar levels and enhanced nutritional quality. Modern wines contain significantly more alcohol than their predecessors. Climate change and the mania (which has now peaked, it seems) for planting cool-climate grapes like Chardonnay and Merlot in unsuitably hot areas where they can quickly over-ripen are two causes. Another is that old wineries lacked temperature control so grapes were picked earlier out of necessity, their lower levels of fermentable sugar (potential alcohol) helping prevent tanks overheating and leading to incomplete fermentations and vinegary wines. But another key reason why contemporary grapes – even from cool-climate varieties grown in cool climates – contain higher sugars is the advent of soluble fertilizers. These feed vines direct rather than via the soil as compost does. Fertilizers promote sugar rather than flavour accumulation, meaning grapes which used to taste ripe at 13.5% ABV now need to be 15% for comparable flavour intensity. In conventional vineyards it is usual to see grapes being picked before a single leaf has fallen, but in biodynamic vineyards grapes should attain flavour ripeness only as the leaves are already starting to fall as nature intended. Horn silica 501 contributes to an alignment of flavour and sugar accumulation, leading to clearer expression of terroir.

Taken from Biodynamic Wine by Monty Waldin published by Académie du Vin Library. It is available here at a 20% off discount for a limited time.

Photo: © Monty Waldin Cow manure is the best all-round manure because generally it contains all the mineral and trace elements needed for wine production