In the winter months we work to improve the fertility of our soils with organic matter, since we are believers in organic and regenerative agriculture for all the different vineyard plots. In Tres Piedras we continue to fertilize as before in our historic Fuentecén vineyards, in the Ribera del Duero Burgalesa. We bury the manure from sheep, cows and horses from organic farms in the center of the vineyard rows. Livestock farms that also support the business fabric, provide jobs for local families living in the surrounding environment and whose passage through the mountains continuously clears the forest mass to avoid fires in summer. The use of manure is undoubtedly one of the most beneficial practices in a circular way.
The properties that winegrowers grant to manure, and especially sheep manure, are many. It is, surely, the best organic fertilizer for the vineyard. It helps us replenish nutrients and improve the biological activity of our soils. We work with a composted manure that destroys possible diseases that are later buried in a “hole” every four vines between the rows of the vineyard, contributing about 10 centimeters of manure. This method was the most traditional until 1975.
Manure creates long-term soil fertility. Its effects are usually present for about four to five years. The soil accumulates humic substances of slow degradation, improving water retention, regulating the pH and temperature of the soils.
Fertilizer in the past
Some had the opinion that the manure was reflected in the wine by a greater degree and color, and that it was perceived in the ripe grape bunches from the harvest.
As sheep manure was not abundant or cheap, that of draught animals was used instead (from donkeys and oxen since horses were expensive and scarce). Useful formulas were sought out with the entry of the herd into the vineyard, or fertilizers were made from rotting vegetables. Some exchanged pruning products for manure, or simply bought a number of garbage carts.
The formulas for applying the “sirle” (cattle excrement) were very varied. In each house there was a “femera” or “himera”, where all the products that could be transformed into fertilizer were put. With a moldboard, two narrow furrows were made in the vine and then the strip; With the hoe the earth was removed and the manure was added. Others made a “hoya” every four vines. The fertilization was done every 4, 5, 7 or 8 years (today we usually do it every three years). It was also made in a central open trench with the bravan and in it the compost was added and buried. The most common was the hole in the center of the rows every four strains.
The entry of the animals into the vineyard was also a form of fertilization. With regard to smaller animals, such as flocks of sheep, there were different opinions as to allowing their entry into the vineyards. In most of the towns the entry of cattle was allowed towards the end of the harvest until the first of March. The owners who did not want them to enter their vineyard had to put a sign or mark for the shepherds, signaling that they could not enter.
In general, and although many vine growers had a flock to have compost, the entry of the flocks has always been negatively valued, although today the value of sheep excrement is recognized, especially for the growth of the vines.
In the case of regular and systematic entry of the flock, the shepherd compensated the owner with the gift of a lamb for Christmas or other festivities. The fertilization, when it was carried out, was spaced out in time so as not to burn the strain. The lighting hole was used to deposit the compostable garbage that was later covered when it was time.