After last years late May frosts we invested in 360 frost candles to cover the full vineyard in case we had a late visit from the cold again. On one hand, we really wanted to light the candles to see if they worked and to get to take some rather impressive late-night snaps but of course, we’d much rather jack frost stayed away. But early this may we saw budburst across half of the vineyard followed by a rather dooming forecast of frosty nights. This meant it was all hands on deck to get the candles set out across the bud burst sections ready to protect this year’s buds if the forecast proved right. Luckily until the buds on the vines burst they have a protective woolly layer to keep them safe from cold nights, so only half our crop was at risk from the cold night’s forecast.
Typically, the frost usually hits in the early hours, so we were aiming for an early night ready for a 3 am alert from the vineyards weather sensor when the sub-zero temperatures were imminent and it was time to light the candles. But that alert came at 10 pm… meaning no sleep for us and a frantic rush to get to the vines and light the candles to hold the decreasing temperature above -1. By 11:30 the frost candles were lit across the sections and working to fight the cold already at -2. Brilliantly it worked, we had thermometers throughout the vines and we could see the temperature was held at 0 in the vines as the air temperature surrounding us continued to plummet. In the end, we spent most of the night below -3 and even reaching -4.5 but through lighting a few more candles when needed the vines stayed at a frost-free 0 degrees until sunrise. You’d think that would mean time for us to all have a snooze and catch up after a long night, but being a small family team it was straight in a cold shower, a few strong coffees and time to run our kitchen and bottle and gift shop. It’s safe to say that was probably the longest day we’ve had and it wasn’t over.
We continued to battle the frost for 2 more nights but thankfully we managed to take shifts and all get at least a few hours sleep to keep us going in the days. The following nights still plummeted to below -3 and started to stretch how many hours of frost candles we had left to burn. By the final night, we only had 4hrs left and sadly we hit -2 by midnight. This meant we had to save the candles for the coldest hours between 3-6:30 am, leaving the vines exposed to -2 temperatures for 3 hours. With the remaining candles, we were able to successfully battle against the early morning drop to below -3 limiting any damage caused. But this meant we did see about 10% of damage to this year’s buds but it is a long way ahead of the 75% we could have had without any protection. 75% damage would of resulted in a loss of over £150,000 in bottles, so it’s safe to say the frost candles proved themselves and next year we will be getting well stocked up ready to battle with the cold!
But what actually are frost candles?
Frost candles or bougies have been used for decades across the globe to protect vines from damaging frosts. The candles we used this year are from Crop Candle Co, a new UK based startup making eco-friendly candles from vegetable wax. The tins are also refillable, so from next year, we will be able to use the same base and slide in a new candle cartridge. Limiting waste and helping to make battling the frosts as eco friendly as we can. The candles work by burning at high temperatures, causing warming to the surrounding 5m of the candle and also helping with airflow to keep the frost moving and away from the vines.
As you can see above our Rondo buds are still looking happy and are continuing to open after the frosts hit. But having now used all of the frost candles at our disposal we just have to keep our fingers crossed that the long-range forecasts are true and we continue to have warmer weather through May.
Join us to go far beyond the bottle and learn about the other challenges of growing vines in Devon on our wine tasting & vineyard tour experience.