Stinging Nettle Liquid Manure is a plant-based spray, the most commonly used liquid manure in organic and Biodynamic vineyards. It is made from the stems and leaves of stinging nettle which are cut before or at the beginning of flowering (Sattler et al: 1992, p.77). Its effect is similar to but more powerful than the fresh tea version of stinging nettle. Stinging nettle liquid manure is generally sprayed on the soil or on vines as a pick-me-up after early spring frost and to prevent early season chlorosis. It combines especially well with horn manure 500 when used as a soil spray. As a mite repellent the cold extract (see essential oils) or tea form of stinging nettle is more effective than the liquid manure. Courtney (1998, p.5) advises using this liquid manure with care “as overuse, say, more than twice in a growing season, can cause the plants…to be more subject to fungus attacks, in the same way that happens when one uses too much raw, uncomposted manure.”
Bibliography
Friedrich Sattler., and Eckard von Wistinghausen, Bio-Dynamic Farming Practice (Bio-Dynamic Agricultural Association UK, 1992) trans. by A. Meuss, p.77.
Hugh Courtney., Applied Biodynamics 24/1998, p.5
Monty Waldin., Biodynamic Gardening (Dorling Kindersley, 2015).
Monty Waldin., Biodynamic Wine (Infinite Ideas, 2016).