
May in the northern hemisphere is when nature is at its most enigmatic: hawthorns are garlanded with clouds of frothy blossom, birds are in full song and hedgerows and allotments alike flourish in the emerging heat of early summer. But, these idyllic signposts aside, for the winemaker it's no month for lazing and dreaming. Here's where the hard few months leading to harvest begin, and they must prepare for the challenges of the growing season, whether potential sunburn, excess vegetative growth, pest control or even a late frost.
The other side of the globe, meanwhile, is experiencing an equally important change: the days are slowly shortening, temperatures have begun to gently drop, and winemakers and their vines are preparing for the sun to relinquish its powers of warmth and sunlight for another year. The toil of harvest is over and – if all has gone to plan – healthy grapes are now undergoing their near-magical metamorphosis from fruit to ferment in oak barrel or steel tank. The pace of life in the vineyard is slowing, nearing to a hush: it's time to prepare for winter.
But while nature begins its slumber, activity in the vineyard doesn't completely shut down: preparations for next year's vintage are well underway, fuelling the vines with the nutrients they'll need to emerge next spring; well-fed, rested and ready for the process of producing ripe, healthy fruit for the new vintage. And with the hottest succession of years on record transforming springs and autumns around the world, growers are increasingly preparing for the freak weather events that now punctuate the traditional ebb and flow of the winemaker's year.
We asked four growers across two hemispheres what May looks like for them.
Northern Hemisphere: New shoots and darling buds
In the vineyard: In early spring, sap begins to rise in the vines and buds will begin to emerge. By May flowering will have begun, with flowers gradually growing bigger until they're ready for pollination and fertilisation, culminating (with any luck) in a crop of healthy fruit.
Christina Wess - Wachau, Austria

While burgeoning green shoots lend nature a sense of invincibility, the threat of damage to new buds lingers ominously in the vineyard at this time of year. 'In spring it can actually be a very sensitive time, because it's when flowering begins,' says Christina Wess, whose joint venture with father Rainer Wess has been producing some of Austria's most exciting wines (no mean feat in a country whose wines are so ripe for discovery). 'While it's a very special time because the vine is 'opening' up so that new grapes can eventually emerge on the other side, it also means that diseases could enter the bud very easily during the flowering and could cause a lot of harm, especially the mildew fungus which is most likely to infect the vine during flowering.' Monitoring vines to make sure there's a good amount of air flowing through is crucial to preventing the onset of these diseases, which can easily ruin or taint a whole crop.
'The neuburger grape, for example,' says Christina 'is a very old and temperamental grape variety. The clusters are very dense and as we don't want any botrytis influence on our wines, it presents a big challenge in keeping the air flowing and rot at bay. This year we'll be managing the berry clusters by using our spraying machine filled just with air (not with any chemicals), spraying during flowering, so the chance of botrytis is minimised naturally.'
Apostolos Thymiopoulos - Naoussa, Greece

'Nature respects you if you respect nature' is the philosophy of Greek winemaker Apostolos Thymiopuolos, a proponent of biodynamic methods who maintains that a deep respect of the soil is the key to creating wines with real character. It's this belief that lies at the heart of his springtime preparations.
By the time May rolls around, Apostolos has already done much of the hard work that will get the vines into good shape for bud-break and flowering to come, undertaking yield-taming pruning, which will encourage smaller yields of more concentrated berries – 'crucial,' says Apostolos 'for a very productive variety such as xinomavro and best avoided on cold days because the wood is harder when temperatures are low and the risk of damaging during pruning is high'. This process is followed by the application of nutrientrich composts ensuring the vines are thriving in time for the growing season.
'Organic principles combined with a use of biodynamic practices gives us a real advantage. By completely avoiding pesticides and chemical fertilizers, we allow the growth of micro-flora, making the soil healthy and well aerated. This means that the roots tend to go deep into the soil to find water and other necessary elements; deep roots make the vine durable and tolerant to other hazards later in the year.'
Southern Hemisphere: A vintage of heat and smoke
In the vineyard: It's a bitter irony that as winemakers return to a way of agriculture that's more attuned to the ebb and flow of the seasons that Mother Nature herself is shifting dramatically out of kilter from traditional farming patterns. It's in the southern hemisphere that the effects of our warming planet are being most profoundly felt, as the devastating recent bushfires in Australia have proven.
Mac Forbes - Yarra Valley, Victoria, Australia

'Obviously Australia was devastated by the fires over Christmas,' says Mac Forbes, the man behind our Blind Spot range and his own Mac Forbes label wines. 'However, in the Yarra Valley we had an extraordinary harvest with cooler temperatures, regular rain and perfect balance in the vines. We did also have a bit of smoke hang around the valley, so we just need to keep assessing the wines for any signs of smoke taint. Fingers crossed our babies are going to be ok. We certainly tried numerous approaches to minimise any pick up of such compounds.'
In autumn and winter, we're already working really hard to build greater soil health: we're busy applying undervine compost as well as reseeding any mid rows with perennial grasses or some clover undervine that will naturally die off in spring. We'll also conduct soil analysis and begin pruning.
Towards the end of the process, as the cellar gently warms in early spring, we really start to see the wines come to life. At this stage we begin preparation of bottling of rieslings and give the pinot and chardonnay wines longer to wake. Sometimes doing nothing is the most powerful thing. Something we humans find very hard to do. It's a bit like cooking with great produce. Don't mess around with it too much!'
Cristóbal Undurraga - Colchagua Valley, Chile

Just as humans turn to nutrient-dense foods to see us through the biting winds and lashing rains of autumn and winter, so too does the soil: 'The vines have worked all spring and summer season to produce these unique grapes, so it needs to be fed,' says Cristóbal Undurraga, who spent many years at his family winery, Undurraga, before setting up his new venture, Viña Koyle, in Chile's Colchagua valley.
'In this way, we return a hand back to the soil that is the vine's source of food. The biodynamic compost we prepare in our vineyard is the balanced nutrients we give to increase the soil biological life, to make them strong and healthy to go to sleep well fed during the recess cycle.' Cristóbal's vineyards have seen unprecedented unsettled weather conditions, meaning the grapes need thorough assessment pre-vinification to make sure the very best wine can be made from them.
'The decision and preparations that we will undertake in the winemaking process will depend on what each grape variety turns out like after the harvest season,' says Cristóbal. For example, 2019 has been the most extreme year of a ten year cycle of dryness. This has resulted in very fatigued vines with low yields, terribly affected by the past 2019 winter, the driest winter of Koyle's 14 years of history, where we had 50% less water than the driest year before, and with 20% of the rain that we expected. Considering this, the yields will be dramatically low and the concentration very intense, making this season a very special one, but one where we have to fine tune both viticulture and vinification.
Making sure the winery itself is fit for purpose is probably the least glamorous aspect of autumn preparations, but vitally important. 'For the vinification process all of our stainless-steel tanks, barrels, foudres and concrete eggs must be scrupulously clean. Most essential of all is to make sure we've got a robust winemaking team. During the year we are three winemakers in charge of the winery, but during the harvest time and vinification process we reinforce our team with six more winemakers who will help in each process of the vinification, to make sure the wine is perfect.'