Humic acids in viticulture
Humic acids in viticulture
How the agricultural turnaround succeeds even on steep vineyard sites
Viticulture is under massive pressure in Germany and the EU. The effects of climate change and the EU agricultural policy with its farm-to-fork strategy are not making things easy for winegrowers. The winegrowers need constructive solutions.
Climate, soil, good wine - a sensitive triangular relationship
Wine is particularly sensitive to climate and soil. Even the slightest changes affect the quality and quantity of the sweet grapes and present the winemaker with various challenges. The vines, which love warmth and light, find optimal conditions on the sunny slopes of the vineyard, for example. At the same time, direct sunlight on unprotected soil increases water loss through evaporation.
Especially on long steep slopes, the fertile topsoil is also endangered by water erosion. Weather extremes such as heavy rainfall carry nutrients in the topsoil away from the vines through surface runoff - water does not seep away and cannot be stored by the soil. Countermeasures such as erosion walls, useful slope vegetation and active humus management preserve the fertile topsoil.
The most important issues in viticulture are therefore water retention capacity and stability of the soil structure.
Well-combined - Efficient humus management with Leonardite and nutritive humus
Integrated viticulture as a hybrid method between organic and conventional offers excellent approaches here. Matthias Porten of DLR Moselle in Germany recommends in this context a humus economy that combines permanent humus (Leonardite) and nutrient humus (green cuttings, manure, marc) in viticulture. In this way, a successive humus build-up is achieved even in challenging vineyards.
Humus formation in steep slopes
Especially in difficult locations the humus content is of special importance. A humus-rich soil works like a sponge. It absorbs water and stores it over a long period of time. In this way, even Lift-up water from deeper layers of the earth can be better used by the wine. The compounds in this sponge, the so-called clay-humus complexes, are very stable and therefore less susceptible to erosion. This is especially advantageous in steep vineyard sites, as heavy rain and storms can do less damage to the topsoil.
Humus - a substance with multiple functions
A further advantage of permanent humus: After the addition of fertilizer, the nutrients are fixed in the soil by the carbon components humic and fulvic acids contain in Leonardite and remain there long-term stability. Additions of Leonardite in the lower vine area lead to an increased ability of the crumb to store and release nitrogen to the vines. The desired C/N ratio of 10:1 represents the optimal balance for nitrogen supply and activation of soil life. The result: sustainable humus formation and healthy plant growth.
In order to be able to meet the challenges of soil fertility and erosion control for viticulture in the coming years in a sustainable manner, it is recommended to build up humus or at least to maintain it in the soil. Leonardite containing humic acid is very well suited as an integral part of such a management concept in viticulture.
What is your strategy in the fight against increasing humus loss? How do you protect your grapes from drought and heat?