VINE TRAINING VINE TRAINING
L. Peter Christensen Fresno County Farm Advisor
Developing a strong and well-formed vine framework and root systen. is the most important goal in vineyard establishment. This is largely achieved through proper vine training procedures during the first four years.
FIRST YEAR. Normally no training is attempted. The main objective is to develop the root system.
At the end of the growing season, during dormancy, the vines are pruned back. Prune to the strongest, well-placed shoot and cut back to two buds. Figure 1.
There are occasional attempts to train vines up stakes the same year they are planted, but usually with disappointing results. The amount of reserves in cuttings or rootings just doesn't provide enough vine vigor to train up a strong, straight shoot to the required height on all vines. The necessary removal of some shoots and leaf area in premature training may actually lessen total root development the first year.
SECOND YEAR. Developing the trunk.
Direct all the growth into a single shoot to train up the stake for the permanent trunk. The remainder of the framework will come from lateral branching near its top.
It is often necessary to hoe or shovel some soil away from each vine before growth begins. This clears away enough soil to make suckering easier, especially the removal of those shoots which arise from near or below the normal soil surface.
After the longest shoots have grown 6 to 8 inches, sucker off all but 2 or 3 upright growing shoocs. Retain shoots which are growing near the stake and can be easily tied over to the stake. Once the longest and best positioned shoot can be easily tied onto the stake without breaking it out, make the first tie. Figure 2.
Tie up the main shoot periodically to prevent shoot breakage and to assure a straight trunk -- about every 10 days.
The extra 1 or 2 shoots serve as spares in case of loss of the originally selected main shoot. However, once the main shoot is 12" long and is securely tied, break out the remaining shoots. Figure 3.
Some growers prefer to delay the beginning of training until the shoots are 12"-18". They then sucker off to a couple of shoots, tie one and take off the spare immediately.
Bilateral cordon training. This system is used for most spur-pruned wine and table grape varieties. Cane pruned varieties, such as Thompson Seedless and Calmeria, are sometimes trained to a short cordon. These short cordons, 10"-14" in length, serve as the permanent renewal area for fruiting canes. However, some growers have experienced difficulty in maintaining a satisfactory renewal zone in such Thompson Seedless vines because of shading out of renewal wood.
Cordons are formed from two lateral shoots or branch canes near the top of the trunk. The main shoot (trunk) is topped when it has grov^ 12"-18" beyond the first '(cordon) wire. Make the cut about 2" below the wire. Figure C-A. This assures that Che trunk v;ill divide several inches below the cordon wire so that the shoots will come up in a gradual bend and not a sharp bend down or over to the wire. Some growers prefer to cut through a node just below the wire. This kills the bud, but leaves a dead stub at the top to tie firmly to the stake, using twine with a clove-hitch tie,
Always make sure that the cop of the vine is tied to the same side of the stake as the wire attachment. The shoots are then in position to be attached directly up to the wire and not bent around the stake over to the wire.
Always top the vine to produce the lateral shoots for uniform cordons. If the main shoot growing up the stake is merely tied down to one side for a cordon, the opposite cordon must come from a smaller lateral shoot. This results in a permanently stronger side and weaker side on cordon trained vines.
Lateral shoots developing from the lower portion of the trunk are removed as they develop. As soon as two top lateral shoots are selected for the cordons and tied to the wire, remove all the remaining lateral shoots down the trunk. Figure C-5.
Tie the two remaining lateral shoots several times as they develop along the wire to keep them straight. Figure C-6. No further training is then necessary for the remainder of the growing season except wrapping or tying growth to keep it supported on the wire.
Head training. This system is used for cane-pruned vines, such as Thompson Seedless, Zante Currant, Fiesta, Black Monukka, Almeria and Calmeria.
Head training for spur priming is rarely practiced in establishing new vineyards today.
The main.shoot is topped when it has grown 12"-18" beyond the "heading-out" point. Cut the shoot 10" below the first wire or cane wire. Tie it securely. Lateral shoots developing from the lower 2/3 of the trunk -- bottom 24"-32" -- are removed, leaving at least 5 lateral shoots at the top. Figure H-5. Wrap this lateral shoot growth loosely onto the wire as it develops to keep it supported on the wire. Figure H-6.
THIRD YEAR.
Overcropping is the most serious error during vine training. It can lead to permanently weakened vines and uneven and poorly distributed spur development. This is controlled by proper pruning, crown suckering and sometimes cluster thinning.
Bilateral cordon training. At the end of the growing season, during dormancy, the two lateral shoots or branch canes are cut back to a proper length. Figure C-7. Unfortunately, no single recommendation can be made for pruning length on all varietlea. It must be adjusted to the variety and vine vigor.
Wine varieties - In most wine grape vineyards, gradually extend the cordons over a 2 to 3 year period, especially with the highly fruitful varieties Rubired and Royalty and those of low vigor.
The only clear cut exception is French Colombard. Extend a vigorous vine of this variety fully in one year.
The following chart groups wine varieties into recommended pruning lengths and bud numbers during cordon establishment:
2 Length of 1st step cordon annual cordon development and length extensions thereafter Poor Moderate Good (maximisn growth growth growth range)
"3-step cordon varieties" cane diam. cv i"-3/8" %" + Muscat of Alexandria, Petite Sirah, Ruby length spur 6"-8" 12"-18" 6"-8" Cabernet, Tinta Madeira, only Royalty, Zinfandel no. buds on 4-6 7-10 4-6 wire (each side)
"2-step cordon varieties" cane diam. ^ ^"-3/8"'U -'1 ^ Rubired, Chenin blanc, Carignane, Palomino, length 6"-8" 12"-18" 22"-24" no. buds on 4 6-8 9-12 6-8 wire (each side) "1-, or 2-step cordon cane diam. 3/8 5/8" + varieties" French Colombard, Emerald length 6"-8" 12"-24" 30"-42" 12"-18" Riesling, Grenache no. buds on 4-6 7-10 10-14 7-9 wire (each side) Exceptions include; Extend French Colombard cordons -V and over in diameter fully in 1-step; the 2-step varieties with cordons 3/4" in diameter and larger are fully extended in 1-step; and the 3-step varieties with cordons 3/4" and over in diameter are extended in 2-steps, Always prune to a bottom bud on the ends of the branch canes if they are to be extended the next year. The shoot from this bud grows from the underside of cane in the direction of the cordon. It makes a straight and eas^'-to-tie cordon extension. It is usually best not to leave spurs the first year the cordon is on the wire. These spurs must come from lateral shoots which are usually uneven in development and in spacing along the branch cane. By cutting all the laterals off, the main (axillary) buds on the branch canes push more evenly and at the same level. The permanent spurs are selected at one time the following year. Exceptions are vines with extreme vigor, such as French Colombard. Leave 1-bud spurs where the branch canes are 5/8" or more in diameter. This helps avoid "blank" areas along the branch canes where buds get "buried" in the fast-growing, large diameter wood. 3 DEVELOPING THE TRUNK CORDON AND HEAD TRAINING yf ii WINTER FIRST YEAR EARLY-MID APRIL MID- LATE APRIL 2nd YEAR 2nd YEAR HEAD AFTER SUCKERINe AFTER SUCKERING TRAINING CANE PRUNING At" '— i: H-4 H-8 — H- 6 LATERAL SHOOTS ■>1 ' MID-LATE MAY MID JUNE AUGUST 2nd YEAR 2nd YEAR End YEAR WINTER WINTER 2nd - 3rd YEAR 3rd - 4fh YEAR AFTER PRUNING AFTER PRUNING CORDON TRAINII^ SPUR PRUNING C-5 ,vlateral shoots MID MAY EARLY JUNE 2nd YEAR 2nd YEAR p«a. C - 7 C- 6 WINTER AOOUST 2nd- 3rd YEAR 2nd YEAR Normal crown suckering in early to mid-April follows these pruning procedures. Rub off all shoots arising from the main trunk up to above the bend of the cordons. This leaves an open, suckered area about 8" wide where the cordons are separated. Also remove any shoots arising from the underside of the branch canes. This procedure not only controls crop during training, but also reduces pruning costs throughout the vineyard's life. Crown suckering permanently removes growing points In unwanted areas which are difficult to completely eliminate in pruning. This is particularly true in the "brushy" varieties Rubired, Royalty, Salvador, and Muscat of Alexandria which will continue to push shoots from nodes not originally suckered out. Table grape varieties - Most table grape growers prefer to judiciously crown sucker during vine training, leaving only those shoots desired for next year's spurs. This greatly limits the crop and permanently removes unwanted growing points in future years. This strict crop controlling allows for 1-step full cordon training in most vineyards; the cordons are pruned back to the point where they are at least 3/8" thick. During early to mid-April, remove all shoots from the underside of the cordon. Retain shoots spaced at intervals of 4"-6" along the cordon. Use caution when training Emperor cordons. Slightly weak vines have a tendency to push end buds only. If the cordon is left too long, there may be permanent blank areas. Cordons of questionable vines should be cut back enough to assure adequate bud break or cut back to the stake to delay cordon development until the vine is stronger. Head training, cane pruning. For vigorous vines prune back to 2 short (10 to 12 buds), well-placed canes and to 2 or 3 well-placed, 2-bud renewal spurs. Figure H-7. Leave only 1 short cane plus about 3 spurs on low to moderately vigorous vines and no canes and 2 to 4 spurs on weak vines. In April remove all shoots arising from the lower 2/3 of the trunk. FOURTH YEAR. Bilateral cordon training, spur pruning. Prune off all shoots except those left for spurs. Determine your spur spacing from the anticipated full cordon lengths and the anticipated total number of spurs per vine. Try to select only those spurs growing upright. Spurs left on the side or underside of the cordon to fill in blank areas should be pruned to only 1 or 2 buds, leaving a bud oriented for vertical growth. Provide for a 6" spacing between the cordon ends of adjoining vines. Remove any shoots arising from the "crotch" where the trunk divides, leaving a 6" to 9" spur- free area. Figure C-8. Head training cane pruning. Prune back to 4 well-placed 12-15 bud canes and 4 to 5 well-placed renewal spurs on vigorous vines. Figure H-8. Leave only 2 to 3 canes plus renewal spurs on low to moderately vigorous vines and none to 1 cane plus renewal spurs on weak vines. FIFTH YEAR. Usually the only training needed is the completion of cordon extensions in replants, weak vines, or varieties of modest vigor. 4 TYING TECHNIQUES AND MATERIALS Tying new cordons at end of ^.econd growing sea.scn, A practical method of tying the cane branches on the cordon wire is to wrap them one to one-and-a-half times around the wire after pruning. This tends to straighten the cane branches and reduces the number of ties needed to support and straighten them. If wrapped more, they may be eventually girdled by the wire and the wire more subject to breakage as the cordons thicken. A good approach is to make a tight tie with twine at the end of a full-length cordon. This girdles the last intemode, giving the desired spur-free area between the ends of adjoining cordons. Materials. Twine or vinyl tape are most widely used. Twine should be tied loose enough to prevent shoot girdling and usually must be cut free and retied for the next season to allow for growth in diameter. Vinyl tape stretches somewhat with vine expansion. It is particularly useful in tying cordons during training. Adjustable plastic ties are satisfactory in all vineyards. However, adjustable aluminum ties are not recommended for wine grape vineyards as they are too easily removed' during machine harvest. Coated wire ties, such as twist-eins, should be used with caution. They can easily girdle a rapidly expanding cane or shoot if not tied loosely and not removed after one growing season. 5 Farm & Home Advisors Office 1720 So. Maple Ave. Fresno, CA 93702 Run June 18, 1976 Rerun June 23, 1978 600 copies Rerun February 11, 1981 250 copies Rerun July 14, 1981 150 copies Rerun Febiniary 24, 1982 300 copies The University of California Cooperative Extension in comDiiance with the oivii Mients Act ot iy64. Title IX ol the Education Amendments of 1572. and the Renabilitalicn *ct of 1973 does not oiscnminate on the basis of race, creed, relipicn, color, national origin sex or mental or physical ha.nd cap in any of its programs or activties Inouiines regardi'j tn s policy may be directed to: Affirmative Aclior. Officer, Cooperative Extension, 317 University Hall. University of California. Berkeiev. California 94720. 14151 642-f!orn CO-OPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS, U.S Deportment of Agriculture, University of Colifornio, ond County of fretno Co-operctmc.