Trellis
Potential for Organic Winegrowers
By Arnie Esterer
Overview
Markko Vineyard started in 1968 as a winegrower to demonstrate the potential for vinifera in the new to be Lake Erie appellation. As a cooperator of Dr Konstantin Frank, his clones and cultural practice were adapted to produce here in the most natural and organic environment possible. Special attention focuses on winter survival. Then to produce estate wines, which reveal with minimal intervention the unique character and terrior for his five great vinifera – Riesling, Chardonnay, Cabernet Sauvignon, Pinot Noir, and Pinot Gris. And finally to market these wines which hopefully capture the essence and character of each variety and vintage to the waiting wine world. This calls for building understanding, demand, and reputation for Lake Erie as a premium wine-growing region of the world. The primary parameter for that requires finding the one or two grape varieties, which can consistently produce fine to great wine.
Markko Trellis
Easily the vine trellis and canopy management control the most vital factors for successful grape growing. So the potential starts here in the vineyard. The evolution of the Markko Trellis over thirty-five years offers a promising system for Lake Erie vineyards, especially those going organic
The early trials started with a mid-wire Casenave pruning where the bi-lateral cordon tied spur-cane wood up to a higher wire. The spur-cane fruiting position used the Macon variation. But the cane tying became costly between 1975 -1985, when severe winter injury and bud kill required many more canes to compensate for damage. So in the early 1980’s with help from Rene Romberger at OARDC Wooster, the bi-lateral cordon was raised to 54 inches.
With the same four spur-cane fruiting positions on the arms, it becomes a no-tie system modeled on the French and German Sylvoz and no-tie pendel bogen. As the buds break and shoots grow the fruiting canes droop as determined by each cultivar’s growth habit. Pinot Gris, Riesling, and Merlot canes droop down while Chardonnay and Pinot Noir canes come down moderately and Cabernet Frank and Sauvignon hold almost to the horizontal plane into the row. The canopy develops differently for each as the shoots and leaves position themselves to the sun. Canopy management standardizes and varies only slightly between cultivars. The higher cordon adds benefits of a warmer micro-climate spring, fall and winter, better air flow and leaf exposure, more ergonomic canopy management and picking zone, open foliage for better spray penetration, and most importantly requires no tying of fruiting canes. The only spring tying required depends on securing trunks and cordon arms to the trellis wire.
One disadvantage of the Markko Trellis arises when the trucks and cordons die and need replacement. This happened only once after the winter of 1993-4 when the vineyard temperature dropped to an all time record low -23° F on January 19. The vines grew back to full production for ’95 vintage, but the cost required cutting out the dead trunks and arms, and then took more than the normal man-hours for the next two to three years to rebuild the cordon. The fall mound-up and deep snow protected the graft zone and trunks up 20 inches.
Canopy Management
Before pruning begins do statistical study for winter bud kill. Use the Dr Vincent Petrucci summary of Russian winterkill categories to establish a years pruning procedure for each cultivar if necessary.
Normal pruning calls for four cane fruiting positions with two bud spurs each and two extra spurs in case of winter injury. Normal pruning leaves 44 buds on 4 x 8 bud canes and 6 x 2 bud spurs. Spacing canes 18 inches apart and to alternating sides of the trellis improves canopy development. For weak vines leave 20 or less buds. Pruning cuttings drop into the mound-up trench and the grape hoe buries them when taking away the mound before bud break. After bud break rub-off adventitious buds, unwanted succors and unfruitful shoots. After bloom start pulling basal leaves around fruit clusters. Beginning mid-July start hedging canopy shoots approximately 24 inches out from the trellis and/or 9 leaves out from the last grape bunch. If shading begins from excessive vigor or many laterals, additional hedging benefits the crop with more air and sunlight. Hedge the tops between 72 and 78 inches above ground and also the bottom canopy at 18 inch up from the ground. The controlled canopy allows better air flow and spray penetration.
Soil & Weed Management
Under-trellis work starts in March thru April with hoe-away of the winter mound.
This uncovers the graft, buries the prunings in the trench, levels the floor, and disrupts the weeds. Before bloom in May the last of the mound comes down and controls early small weeds. During late June, July and early August, the grape-hoe undercuts weeds and loosens the soil about 18 inches each side of the vines. The grape-hoe does the first mound-up mid August on for final weed control before harvest. The dual disc plow like the one at the grape branch does the final mound-up for winter graft protection. This also leaves the trench in which to bury the prunings from next spring.
Spring disking may be needed to level the floor after mound take away and early cover crop suppression. Management of row middles allows weeds and grass to grow and monthly mowing controls growth. Bi-annual studies by Brookside Labs show soil status and recommendations for fertilizer. For the past two years composted mulch spread down all rows started to follow the recommendations of Dr Harry Hoitink for more organic fertilization practice.