- Planting and complantation
Today, we no longer plant. Instead, we only replant (after grubbing) or complant (also called racottage, which consists of replacing dead vine trunks in situ) because we do not have enough new soil that has not yet been cultivated in our appellations.
As explained above, we replant after the soil has undergone a long period of biological regeneration. After uprooting the old vines and removing the large roots of vines that are then recycled as firewood, a succession of various crops are planted to restore the soil’s potential which was more or less eroded by single-crop farming. This can also be an opportunity for correcting any imbalances in the mineral composition revealed by analysing the soil (0-30 cm) or subsoil (30-60 cm). We then proceed with what we call “deep manuring”, which aims to compensate for any deficits occurring in all or part of the life cycle of the future replanted vines. We systematically use certified natural mineral fertilisers that are compatible with organic agriculture standards. Since introducing our method for regenerating the soil prior to planting, we generally have not needed to add much organic fertiliser, which proves its effectiveness. The total proportion of organic matter (OM) prior to planting now ranges between 2.0 and 2.5%, which is not very high, but is nevertheless sufficient for the vine, provided that good soil management is ensured afterwards. We have to overcompensate for the annual loss of humus by carefully controlling cover crops, the natural return of organic matter, and regular compensatory fertilising for a rapid, but not excessive input. The Carbon/Nitrogen ratio (C/N) of the fertiliser must be between 10 and 15 in order to maintain good biological activity without adding minerals too quickly (C/N <9) or coming to a standstill for too long (C/N>20) and possibly causing a lack of available nitrogen for the vine. The objective of having organic matter content that is in proportion to that of the fine elements (Organic Matter/fine silts + clays > 0.15), ranging between 2.2 and 3.5% (over 0-30 cm, with a free/bonded OM proportion of 70:30), is reached gradually over the course of two to five years. If compensation is needed, we must use an organic fertiliser combining plant carbon and animal nitrogen (composted straw manure, complex compost) in balanced proportions, without burying the fertiliser too deep to ensure it remains active.
The planting is conducted using rooted grafts provided by the vine nurseries, which are either organic or non-organic, depending on the availability on the market, but this issue is not very important because the vineyard will in any case be managed according to the Agro-Synergic approach. However, the type of graft is an issue of concern because the grafts have yielded varying levels of quality for several years now. Our Bordeaux grape varieties have not been as affected by this as Syrah, for example, which has been much more problematic due to evident antagonism to certain rootstock clones and the grafting method (omega graft), which is now widely used. The poor formation of a graft can have dramatic consequences, which are unfortunately difficult to control, since they are sometimes revealed several years later. However, the technique used to perform an omega graft is structurally inadequate. To begin with, the contact area for the cambial tissues is very small and fragile, since plants with the same diameter and shape should be used. Worse still, this grafting technique, which has been mechanised for efficiency purposes, consists of taking a cross-sectional cut of the plants, which tears the fibres and causes necrosis, yet only a clean, oblique cut is suitable for the plants. In addition, the male and female plants used in Omega grafting give the impression that they are strong, but since the affected tissues that are joined together are the pith and xylem (wood), they can neither be bonded nor regenerated, due to the flawed vascularisation. As a result, the vineyard plots with grape varieties that are most sensitive to these fungi are decimated and ready to be torn out, whereas the least sensitive varieties are in an advanced state of deterioration. The mechanical grafting of grapevines therefore reduces the life expectancy of modern-day vineyards.
We therefore miss the whip and tongue, cleft and in situ grafting methods used for former plantings (we started by planting the rootstock in the ground and then performed the graft in situ one or two years later with a cleft or whip and tongue graft, depending on the diameter of the stock; we planted our oldest plots from 1970 this way). This grafting method is much less interesting for vine nurseries because it is not as profitable, but I believe it is much more interesting in the end for winegrowers.
- In the medium term, we plan to schedule our replanting and complantation plans by ordering the rooted grafts we need well in advance from craftsmen who are able to perform this desired ancestral technique, rather than working with large industrial groups. Another option is in situ grafting, which we used up until the 1970s and which provides excellent results, but requires a little more patience.