Fertilising the vines is achieved by ploughing fertiliser into the ground between the rows of vines. Sergi and Anton plough fertiliser into alternate rows so that one side of the vines gets fertiliser each year. Next spring, they will do the same down the other side, and so on. This is not simply to save time, but rather that some of the elements used in the fertiliser are absorbed into the soil very slowly, and there will still be goodness in the earth from last year. Ploughing the fertiliser in gets it close to the vines roots, and avoids provoking excessive weed growth on the surface.

Calculating the quantity of fertiliser per vine is a rather more complicated affair than may appear at first sight. In principle, they try to give each vine around 200 grams, but as the granules fall freely into the plough, it requires a delicate combination of the size of the hole at the base of the funnel and the forward speed of the tractor to ensure that each vine gets the correct dosage. In the photo on the right you can see the blue-grey granules as they pour into the blade of the plough. Although there are now much more sophisticated machines available, this is still the most used machine in the area due to its simplicity and robustness.

The exact composition of the fertiliser varies from year to year - more nitrogen for more vigorous growth, other minerals influence the vine in different ways. This year, on the recommendation of the oenologist at the Vila-Rodona cooperative, they are using a slightly higher potassium content that should give the grapes a slightly higher sugar content. As potassium is absorbed by the soil very slowly, this is done in November/December, whereas the nitrogen contents (much more quickly absorbed) are spread in March. Overdoing the dosage of a largely nitrogen based fertiliser would result in a larger crop of lower quality grapes, and may have other undesirable effects on the grapes. The vines would produce much more foliage, which in both impedes the ripening process, and greatly increases the risk of fungi attacking the grapes.