Liquid Manures | Liquid manures are made by leaving plant material to decompose and ferment in water over a period of days, weeks or even months. Typically wine-growers fill old barrels with around 100 to 200 litres of rain water, plunge as many armfuls as they can of whatever it is they are macerating in the water (5-10kgs is normal), then leave the mixture to warm in the sun. This is called passive brewing. Wrapping the plant material or animal manure in cheesecloth or using wooden batons will keep it submerged. A set of Biodynamic compost preparations 502-507 can be added prior to the soaking period. For this the five solid biodynamic preparations 502-506 can be placed in balls of compost wrapped in a cheesecloth and either dropped in directly or suspended using string from a cross bar. The valerian 507 liquid can be dripped in directly. The growth of beneficial micro-organisms can be encouraged in liquid manures by adding a similar range of foods to those used in compost teas, then aerating to encourage the microbes to reproduce whilst making the liquid manure smell nicer. Bouchet (2003, p.156) says liquid manures smell strongly even when diluted 1:10 in fresh water for use on the soil or 1:20 for use on vine leaves, and must be used with care on vineyards after flowering if the taste of the wine is not to be impaired. Excessive use of liquid manures, especially those which have not been aerated, is discouraged in wine-growing. See plant-based sprays.

Bibliography 

François Bouchet., L’Agriculture Bio-Dynamique (Deux Versants, Paris, 2003), p.156.

Monty Waldin., Biodynamic Gardening (Dorling Kindersley, 2015).

Monty Waldin., Biodynamic Wine (Infinite Ideas, 2016).