Tree Grafting

Tree Grafting

Tree grafting is an ancient horticultural technique that involves joining two plant parts so they grow as one. Grafting allows growers to combine the desirable traits of two different plants. The “scion” is the upper part of the combined plant that will produce fruit or foliage, and the “rootstock”, or the lower part of the combined plant, consists of the root system.

The Side-Veneer Graft
The side-veneer graft is a specific method used primarily for conifers, evergreens, or “top- working” established trees. Unlike other grafts where the top of the rootstock is removed immediately, the veneer graft is performed on the side of the stem. This allows the rootstock to keep its leaves initially, providing the energy needed to heal the union before the original top is eventually pruned away.

1. Preparation and Timing
• When: Best performed in late winter or early spring (when the rootstock is just waking up). 
• Rootstock: A healthy, established potted conifer (usually 1-2 years old) with a stem diameter similar to or slightly larger than your scion. 
• Scion: A 4-6 inch long piece of dormant, terminal (uncut tip) growth from your desired conifer variety, about the thickness of a pencil.

2. Tools Needed
• Grafting Knife: Must be razor-sharp and sterilized with isopropyl alcohol.
• Binding: Grafting tape, rubber budding strips or rubber bands.
• Sealant: Grafting wax or wound sealer (optional, depending on the tape used).

3. Step-by-Step Procedure

Step 1: Prepare the rootstock:
• Select a smooth, branch-free area on the stem of the rootstock, preferably near the base.
• Using your sharp grafting knife, make a long, shallow downward cut about 1-1.5 inches long through the bark, just barely nicking into the wood. Leave the flap in place.

Step 2: Shape the scion:
• You want the base of the scion to closely match the cut surface of the rootstock.
• Make a long, flat, sloping cut on one side of the base of the scion. This cut should be equal in length and angle to the exposed cut on the rootstock.

Step 3: Joining the rootstock and scion:
• Insert the scion into the flap of the rootstock.
• Alignment: Ensure the cambium layers (the thin green layer under the bark) of both the scion and the rootstock meet on at least one side. If the scion is thinner than the rootstock, offset it to one side so the green lines touch.

Step 4: Securing the graft:
• Wrap the union tightly with grafting tape or rubber strips. Start from the bottom and wrap upward like shingles on a roof to keep water out.
• Ensure the scion is held firmly against the rootstock so no air gaps remain.
• Seal the graft area with grafting wax or wound sealant.

After Care: Keep the grafted plant in a shaded, humid area for 4-6 weeks. Once the union is calloused and the scion shows new growth, gradually prune back the top of the rootstock over several weeks to redirect all energy in the new scion. Don’t allow the soil to dry out, but keep water off the grafted area. Your grafted tree is ready to plant when the graft is fully healed, rootstock shoot is fully removed and the scion shows vigorous, sustained growth.