Towards the harvest between drought, Easter frosts and hail: but the Italian vineyard resists

In the Italian vineyard, it is already time for balances, because with the end of July is approaching, inexorable and expected, the preparations for a harvest accompanied by good premises and by a situation, on the whole, positive, as it is told by the report, Region by Region, of Assoenologi, Ismea and Uiv. Starting from the Center-North, delays in the flowering will determine a delay in the harvesting of one week, because of the negative thermal anomalies recorded in April and May.
Crucial moments of the vintage were, in a negative way, the frosts of the week just after Easter of April 7, 8 and 15, with minimum temperatures going down even more than 4 degrees below zero: damages were initially very important, then some vineyards, where the vegetative state was still at the beginning, resumed in a pretty regular way, however at a productive level there are differences not only from area to area, but also from vineyard to vineyard. In many of the affected areas - from Tuscany to Sardinia, from Umbria to the Adriatic regions as well as Foggia - damages have been important and did not allow a new budding, whereas in other areas losses have been partially reabsorbed.
Some further problems are linked to the fluctuating climatic trends of June and July, when important thunderstorms occurred, accompanied by exceptional hail storms, especially in the North East. At the same time, Central Italy is facing scarce water resources and exceptional peaks in temperature, especially in Tuscany, but also in the South, especially in Salento. Heterogeneous are also the indications related to a possible advance or delay in the ripening of grapes compared to what can be considered as the “norm”. In short, a mix of issues that have reduced production expectations, although it is still too early to give quantitative indications that, as always, Assoenologi, Ismea and Uiv will discuss in the September report.
At a regional level, the report on the climatic and vegetative trend signed by Assoenologi, Ismea and Uiv, starts from Friuli Venezia Giulia, where dry autumn and particularly rainy winter, associated with extraordinary snowfalls in the mountains, certainly influenced the vegetative delay of the vine that this year started towards mid-April. The exceptional April frost hit the Region creating some isolated damages in the valley floors and in the areas near water courses. Problems were very limited because the vegetation was just developed on early varieties such as Glera and Chardonnay. At the beginning of June the flowering started and thanks to favorable climatic conditions it took place in the best way. During the growth of bunches, there have been limited attacks of downy mildew, especially in vineyards with little aeration: however, the overall sanitary conditions did not cause any concern. The current hot and windy climate, accompanied by African anticyclonic fronts, leads to some drought problems in the hills and the need for emergency irrigation especially in vineyards cultivated on loose soils.
In Trentino Alto Adige the situation is good: the vegetative cycle and the phenological phases are so far regular. Apart from some minor frost damage to early-ripening varieties, such as Chardonnay and Marzemino, no other problems have emerged to date. The intense hailstorms of July 22 mainly affected the Rotalian plain, for a total of about 500 hectares of vineyards, and also Val di Cembra, but it is necessary to wait in order to understand the real damages. Spring temperatures, lower than usual, caused a vegetative delay estimated in 10 days in low altitude vineyards of Alto Adige, more regular in vineyards above 4-500 meters of altitude. The warmth of the last weeks is making up in part the delay accumulated in April and May, even though the beginning of the harvest could be delayed compared to the previous one.
In the western area of Veneto, after a spring that has seen a return of cold weather and scattered frosts, sprouting has been delayed up to 15 days. Today this delay is between 7 and 10 days. The start of the vegetative cycle in the eastern part of the country has been delayed compared to last year, and during the first period of the vegetative cycle, there have been abundant rainfalls and temperatures below the seasonal average, while in some areas the high humidity has caused attacks of fungal diseases. The weather situation then stabilized and from May on, temperatures reached normal values. In the months of May and June the passage of disturbances created weather phenomena even of intensity, affecting the territory of the Central Eastern Veneto in a random way, with hailstorms that in very limited areas caused significant production losses. Currently, the ripening of early grapes, also due to the current temperatures, is expected between late August and early September with a delay of about 10-15 days compared to the 2020 harvest. It is already evident a decrease of bunches on early varieties, such as Pinot, Chardonnay, whereas for Glera the number of bunches, which are very elongated and scattered, reflects the average.
In all the wine areas of Lombardy, there is a good condition of the physiological and sanitary condition of vineyards, despite the strong hailstorm which affected hundreds of hectares in the north-eastern side of Oltrepò Pavese, already affected by spring frosts. Even in Franciacorta, some areas were affected by the frost at the beginning of April, and the situation got worse after the violent hailstorms of the second half of July which mainly affected Adro, Erbusco, Calino, Capriolo, Passirano and Monterotondo. Although the correct estimation of damages is to be quantified in the next weeks, healthy bunches are enjoying a good vegetative state, also thanks to the last rains, which rebalanced the water regime. Fortunately, the Lombardy side of Lake Garda has been spared from the late frosts as well as from the extreme weather events which have hit the Veronese side during the last week.
In Piedmont, there is a rather heterogeneous panorama but in general terms, it is profiled a harvest in “normal” times. Frosts after Easter have affected many vineyards, with a patchy distribution, however, damages are still localized. There was a pretty cold climate until the end of May, followed by a month of June among the hottest months of the year with a rainfall definitely limited, at the limit of water stress manifestation, especially in the south of the region. Thunderstorms with hail at the end of June affected the North of the Region, but also the South, in Roero and in the surroundings of Albese.
In Emilia Romagna, after a winter with modest rainfalls and quite high temperatures for the period, the vegetative recovery for all varieties was fast, from March 27, when the maximum temperatures rose above 20 degrees, to March 31 at 26 degrees. The damage caused by the April frosts immediately appeared very important, especially in the valley floors: in the first weeks of April, there were cold temperatures, especially at night, which not only caused cold damage to some vines (Lambrusco Grasparossa in the foothills of Modena) but also delayed vegetation by about 10 days. On the whole, the quantitative damage was mitigated thanks to the recovery of the plants, with the growth of many shoots only partially necrotized after the frost, and also for the emission of bunches from secondary shoots. From a phytosanitary point of view, grapes are generally excellent. In the non-irrigated hillsides it is possible to see foliar damages due to water stress, and in this sense rains at the beginning of the veraison will be fundamental, when the plant has a strong need of water: currently, drought is the real unknown factor.
In Tuscany, the last months of 2020 and the first months of 2021 showed abundant rainfall, which provided the vineyards with an excellent starting water supply. The first buds of Sangiovese appeared between the end of March and the beginning of April, with a slight delay on the 2020 vintage. The second half of April brought with it a sudden lowering of temperatures with intense frosts (down to -7/-8 degrees) which affected the valley floor and vineyards below 100 meters above sea level. With the return of warm weather in May, vines could develop with good vigor, recovering the delay of development caused by late frosts. The flowering, between May 20 and 25, benefited from a dry and slightly windy climate which led to an excellent fruit setting. The climate tended to be clear in May and June, limiting the development of diseases and ensuring the excellent health of the plants. The presence of important winter water reserves postponed possible water stress to the second half of July, allowing a good growth of berries. Currently, we are starting to see light signs of veraison in the warmest areas of Tuscany, which suggest a harvest in line with the period. Here and there are some initial problems related to drought, however, they are not worrying too much.
Similar is the situation in Umbria where, after the important losses caused by frost in some areas, currently there is a good health of vineyards with some well-founded worries because of the prolonged absence of rainfalls. Remaining in Central Italy, it is reported a normal development of the vineyards in Latium with about one week in advance. Frosts did not create great losses of product, whereas now high temperatures are worrying because they favor pathogenic attacks, such as powdery mildew.
In the Marche region, the winter season was warmer than normal, as has been the case for several years now, but with more abundant rainfall than normal, especially in December and January, little rain in February, as well as throughout the spring with a negative record of rainfall that has not been recorded since 1961. Except for sporadic events, limited rainfall even in June, and only in July were recorded expected and healthy rainfall. As far as temperatures are concerned, after the negative anomalies of March and April, the value of May was substantially in line, the average temperature “exploded” again in the month of June in which it exceeded by 3 degrees the reference norm of the period 1981-2010. The budding of the main varieties took place with a delay of 7-10 days on 2020. A delay that the vineyard is recovering, as verified in the first surveys of the ongoing veraison, is also a consequence of the thermal peaks alternated to the rains, which are regulating the metabolism of the vine. The situation of diseases is pretty good because of the absence of downy mildew and moth while powdery mildew has appeared in some areas. In a few days, it is expected the veraison of early grapes, while the vegetative level, a little bit low compared to the norm, is generally regular and of good vigor.
Going down towards South, in Abruzzo and Molise there were scarce rainfalls until April and in the spring months therefore young vineyards suffered a lot, at least where there was no possibility to irrigate. From the end of April until the middle of July there was no relevant rainfall and vine showed once again its great capacity of adaptation and resilience to extreme situations, being able, from a physiological point of view, to react and adapt to conditions of scarce water and sudden heat stroke, modulating the rhythm of growth of the various phenological phases. Currently, all vines, both early and traditional, have a phenological delay of 5-7 days. The high temperatures of the last weeks (first half of July) have practically stopped the vegetative growth; only the early varieties have started the veraison while the traditional varieties are still in the phase of berry growth.
In Campania, the vineyard experienced rather mild winter temperatures, which continued with almost one degree above average until the beginning of March, and with abundant rainfall, leading to a good vegetative recovery, slowed down however by the important drop in temperatures at the beginning of April, with snowfalls at high altitudes and some frosts lower down. From May on, temperatures were slightly higher than average, with a prolonged absence of rain, limiting the development of diseases and allowing a good flowering and fruit set. The rapid transition to the pre-closing phase of the bunch, which had a lot of flower residues, determined the development of bunches that tended to be more sparse. With the rains of mid-July accompanied by a drop in temperatures, a delay of 7-10 days on the phenological phases of the vine is confirmed at the moment. In general terms, climatic conditions allowed the management of vineyards without any particular problem.
Going down to Apulia, the situation is absolutely under control from a phytopathological point of view. Also the vegetative development is good with very luxuriant vineyards even though these last weeks have raised the attention on the persistence of drought and excessive heat. At the moment the only certainty is that the vintage is going towards a consistent delay in ripening. The first surveys on Chardonnay indicate a vintage delayed of about 10 days in comparison to last year, but also in comparison to the average of the last 20 years.
In Calabria, despite the adversities caused by frosts, vineyards are in an optimal vegetative state even though harvesting forecasts are very non homogeneous, even from vineyard to vineyard of the same area: at the moment, 10 days of anticipation are expected.
The Sicilian vineyard is also in good health, where, after a winter once again generous from the rainfall point of view, in particular during the months of February and March, which saw accumulations above 200 mm, spring was definitely dry with a limited number of events and quantitatively not significant. In particular, the month of April was highly anomalous, during which rainfall was absolutely negligible, with an average accumulation of 3 mm, the absolute climatic minimum. In the second half of June, moreover, temperatures were very high, with peaks up to 45° C (45° F) in many areas of the island, leading to some scalding of the most exposed bunches. During the delicate phases of fruit setting rains were practically absent, limiting to just two events, with negligible quantities. In this period, temperatures have lowered, slightly reducing the percentage of fruit setting in some varieties. Infections, both Peronospora and more dangerous powdery mildew, have been limited and of little importance, producing only some localized outbreaks. In general, where treatments have been done with care, given the current climatic trend, it is expected an excellent vintage, both for quantity and quality.
Lastly, Sardinia, which had a good supply of water, as from January to March there were abundant rainfalls. From March to now, on the contrary, there have been very few rainfalls, limited to some areas, which are creating some problems in non-irrigated vineyards. From a climatic point of view, the sore point has been the frosts of April 8-9, which have strongly affected the northern part of Sardinia, in particular the area of Alghero and Gallura, where 40-50% of the vineyards have been damaged, milder in the area of Oristano and in all the valleys of the island. The higher temperatures and lower rainfall in recent months have instead favored a better health status of the grapes with the almost total absence of downy mildew and limited attacks of powdery mildew, currently offering healthy grapes throughout the territory. From a phenological point of view, there was initial anticipation, subsequently reduced by the phenomenon of April frosts and by the high temperatures of June and July, which in turn created stress phenomena to the plants, bringing the phenological cycle of the plant back in line with the other vintages. At present, it is believed the beginning of the harvest will be in line with last year's, with the sparkling wines to be harvested within the first week of August, with a very positive forecast in terms of quality.