Pruners possess a small, curved set of blades that are designed to cleanly and easily slice through small branches and shoots in trees, bushes and plants. Correctly sharpened pruner blades won't tear or otherwise damage the branch, allowing it to heal properly and reducing the risk of rot or insect damage.
Clean the pruner blades of any dirt, rust or tree sap. Use a rag soaked in mineral spirits to remove sap.
Open the pruner blades completely.
Begin sharpening the blades. Place the end of the sharpening stone on the outside of one of the blades, where it meets the other blade.
Push the stone away from the base of the blade toward the tip of the blade. At the same time slide the stone up and off of the cutting edge of the pruner blade. Repeat this process several times.
Sharpen the other pruner blade in the same manner.
Clean the newly sharpened blades with a rag and mineral oil. This will remove any metal filings left behind as well as protect the blade from oxidation due to moisture.