Chris Cooper and Rob Saunders, vine specialists in the Hutchinsons Horticultural team, discuss the season to date in vineyards.
The hot summer of 2018 broke all UK records for grape production, but such a “monster vintage” will mean growers should be thinking ahead to ensure next year’s crops have a chance of repeating the performance. Thinking ahead involves controlling any weeds, creating a feed plan based on the analysis of soil samples from the vineyard and protecting vines from trunk diseases.
Weed control – Kerb Flo (propyzamide) is approved for use within the vine row and as a residual it will control established weeds including grass weeds, Black Nightshade, Creeping Buttercup, Black Bindweed, Knotgrass, Redshank, Fat-hen and Chickweed. The product can only be applied between 1 October to 31 Jan. Contact-acting herbicides such as some formulations of diquat and glyphosate are used for burning off weeds within the rows. Shark (carfentrazone – ethyl) and Finalsan (pelargonic acid) are also approved for use under vines but Autumnal use can give poor results unless used in mixtures.
Out of season is the time to take soil samples and plan to correct any obvious deficiencies. Get the sampling done early to allow time for analysis and putting together a nutrient plan for next spring. With the bumper crop this year, there is more likely to be a need for correction. Sampling can be done using precision farming techniques such as Omnia.
Grapevine trunk diseases (GTD) can infect via pruning wounds. Symptoms to look for (and areas to be marked out) are where you see sudden death of the vine, poor vigour in the cane and cane bleaching. Pruning, already underway in some vineyards, should be avoided in wet conditions, as this encourages spore and mycelial growth. Garlic barrier (from Solufeed) with its new organic certification has been used in vineyards to seal cuts for three pruning seasons. Data from trials worldwide, specifically in Australia and the US, support its useful effects reducing pathogen entry via new pruning cuts.
Nativo 75WG (tebuconazole and trifloxystrobin) received an EAMU in October in for use on wine grapes at a dose rate of 0.18 kg/ha and can be used early in the season to give additional protection against GTD’s.
On 22 November, Denbies Wine Estate hosts the inaugural WineGB technical conference organised by the Viticultural Working Group. It has a great line up of speakers, one of which will be Rob Saunders talking about Spotted Wing Drosophila – An industry perspective of current findings and future implications. We look forward to seeing you there.