Horn manure 500P (Thun)

What is horn manure 500P?

Horn manure 500P, sometimes called “prepared horn manure”, is a further step from classical horn manure 500 developed by Maria Thun in the 1970s. The difference lies in the application, not in the making: 500P is horn manure to which the six compost preparations 502 to 507 (and sometimes valerian in addition) are added in small pinches during the stirring. The idea behind it: what otherwise reaches the field only by way of the compost is brought straight onto it with the horn manure — a collective preparation in a single application.

500P is thus a pragmatic concentrate for practice, not a new preparation in the sense of the Steiner canon.

Origin and context

Maria Thun had worked since the 1950s on empirical and experimental refinements of the biodynamic method. 500P arose from the observation that many farms — those in conversion above all, or with thin compost husbandry — were not using the compost preparations regularly enough. Thun proposed 500P as a simplification fit for everyday use: anyone stirring horn manure anyway can take the effect of the compost preparations along in the same operation.

Making it and using it

The making of plain horn manure 500 stays unchanged: cow dung in the cow horn, buried over winter, lifted in spring. The preparing happens only at the stirring: before the hour of stirring, about one gram each of the six compost preparations (yarrow, chamomile, stinging nettle, oak bark, dandelion, valerian) is put into the water — often valerian as well, as an additional warmth. Then stir and spread as usual.

Quantities and volume of water correspond to classical horn manure (see spreading the preparations). 500P is mostly used in spring, when the compost preparations are meant to work into the soil impulse in any case.

Demeter status

500P is not listed explicitly as a preparation in its own right in the Demeter standard. The classical applications — horn manure on its own, compost preparations in the compost — are the standardised form. Anyone using 500P does so by their own decision on the farm; the farm stays in keeping with Demeter as long as classical horn manure is spread regularly and the compost preparations are used in the compost as intended.