There are several reasons for that all linked with the ‘terroir’. ‘Terroir’ is a simple French word to describe climate, soil and human actions/factors on the vine growing.
Climate
The climate in Maharashtra is more continental than Bangalore, means that temperature gets very warm in summer (April, May), up to 40-45 deg. On the contrary, Bangalore temperature is much more constant over the year, around 25-30 and up to 35 deg during summer. Heat unit is what we could call the quantity of energy from the sun per day that the plant gets. There are consequently more heat units in Maharashtra, thus ripeness comes faster, few days less than in Bangalore.
Rain is also coming earlier in Maharashtra, first rains come in April. That could spoil the crop by development of rot on grapes and dilute the concentration of sugar and others components in the berries.
Soil
The soil in Maharashtra is dark, compared to Bangalore soil which is brown-red. Dark color gets warmer from sun light and induces senescence of roots in surface and could affect the end of maturation in extreme instances. That is also one of the reasons why temperature is higher in Maharashtra.
Human intervention
Knowing the previous points, we can adapt the production to those climate and soil by pruning one month earlier, in order to escape from the big summer heat and the earliest rains. On the other in Bangalore, we keep the harvest period in April, to get the optimum maturation of the grapes according to our own microclimate.
One more important point for this time difference is that unlike Maharashtra, Karnataka apart from a South-West monsoon (which gets over by 15th Sept.), also gets the North-East Monsoon, which is from 1st Oct - 15th Nov. In fact, in our earlier history, we never pruned before 15th Nov & then sometimes harvest went upto end May. As we improved our viticulture practices, we started pruning on 1st Nov to bring the harvest forward. We are adjusting the maturation period of our grapes to the optimal period of sun, thus the development of required flavors and sugar is easier and homogeneity of crop is insured.
Thibaut Verdenal
- Grover Wine Maker