Whip Grafting

Bluefford G. Hancock, George Ray McEachern, and Larry A. Stein
Texas Agricultural Extension Service

WHIP GRAFTING (also called splice or tongue grafting) is one of the oldest methods of asexual plant propagation known. It is the predominant propagation method used on apples and is widely used on pear. Although most grapes are grown from cuttings in this country, whip grafting is the standard when they are propagated. Whip grafting has been the primary method employed in propagating pecan nursery stock in the southeastern United States. This technique is also used to some extent in the Southeast and west to Louisiana for top-working larger pecan trees on the above-ground portions. Since successful whip grafting is closely correlated to the presence of high humidity, this method has not been used widely in the drier sections of Oklahoma, New Mexico and Texas. A major strong point for whip grafting nursery stock is the smooth and straight trees that are produced by this method.

Step 1. Seedling rootstocks, 1 to 2 years of age, are usually used for whip grafting purposes. The diameter at the upper portion of the root generally ranges from 3/8 to 3/4 inch, however, stocks up to 1 inch in diameter can be used. The season for whip grafting is February to early or mid March in most areas, or while the stock is dormant.

Step 2. Select 1-year graft or scion wood in the dormant season. Size should correspond to size of available root stocks. Each graft stick should contain at least two sets of buds. Graftwood should be selected and stored in late January. A knife with a thin blade shaped as shown above and made from high-quality steel is desirable for whip grafting. Make sure that the knife will take a fine edge and hold it under a heavy work load. 

Step 3. Expose about 4 to 6 inches of the upper portion of the tap root. Where only a few trees are involved, the entire process of soil removal may be accomplished by the use of a hoe. However, if the graft is secured with poly tape, the graft can be placed above the soil line as well. Grafter is poised to make initial slanting cut on rootstock. Note the slight angle of the knife blade. The stock of the seedling rootstock fits into the groove or notch formed by the thumb and forefinger of the knife-hand. This serves to stabilize the stock and to provide a guide as the cut is made. 

Step 4. Pull the knife upward with the blade angled about 45 degrees, making a smooth and straight diagonal cut. This slanting straight-plane cut should be 2 to 3 inches long. Try to make this cut with one stroke of the knife.

Step 5. Place the knife at a spot on the slant cut approximately one third of the distance from the tip to the heel (or bottom) of the cut. Make a “tongue” cut by working the knife blade downward for a distance of 1 to 1 1/2 inches. Take care to prevent splitting the stock. Use fore-finger of the left hand to brace the stock. Note in the inset that the cut is neither parallel to the grain of the stock nor to the slanting cut, but is actually between the two.

Step 6. Hold the scion wood securely in the left hand, but with care to prevent injury to the buds. Place knife at an angle to the scion and make a slanting cut (see inset) by pushing the blade away from the body. This straight-plane cut should be made as similar to the cut on the rootstock as possible.

Step 7. Make the “tongue” cut on the scion by placing the knife blade at a point about one-third of the distance down from the tip. Pull the blade downward at an angle that is about halfway between the grain of the scion and plane of the slant cut. (See inset.) Note that the thumb of the knife hand serves as a guide for a controlled cut, while the forefinger of the left hand stabilizes the scion. 

Step 8. Slip the plane cut surface of the scion down to the slant cut of the stock until the two “tongue” cuts mesh together. The cambium layers of the stock and scion must be aligned if a union is to be obtained. An uneven or wavy cut will result in gaps between the two surfaces. If the two cuts are made properly, the stock and scion will appear to be one. (See inset.)

Step 9. Wrap the graft securely with masking tape or a special grafting tape. Polyethylene budding tape may be used for this wrap, but may require cutting at a later date to prevent girdling. Make certain that the cambium layers of the scion and stock remain aligned during the wrapping process. Note in the inset that the wrap extends from below the graft union to a point slightly above. This is essential to prevent drying of the cut surfaces before callousing takes place.

Step 10. Firm moist topsoil around the whip graft to prevent drying. Ideally, the soil should cover all of the taped area with the lower bud group on the scion exposed. The cut surface at the top of the scion stick may be coated with orange shellac or with wax to prevent excessive drying. Of course, if the graft was placed above the soil line, this step would not be necessary. Remember, regardless if the graft is placed above or below the soil, the tape which originally secured the graft must be removed. This can be done as late as one year, but preferably after 3 to 4 months.

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