Maintaining garden shears with regular cleaning and care preserves their sharpness and extends their lifespan. Clean, sharp blades create smooth cuts that allow plants to heal faster, reducing the chance of infection from plant pathogens. Neglecting this maintenance leads to sticky, dull blades that crush plant tissue, promoting the spread of disease. A simple routine of cleaning, sterilizing, restoring, sharpening, and oiling is necessary to keep your shears working like new.
Initial Cleaning and Sterilization
The first step after using your shears involves removing debris, soil, and sap. Scrub the blades with warm, soapy water and a stiff nylon brush, paying close attention to the rivet or pivot point where sap tends to accumulate. For sticky plant resins, apply a solvent like mineral spirits, turpentine, or a citrus-based cleaner to a cloth and wipe the blades clean before rinsing them thoroughly. Removing this material is necessary because it prevents sterilizing agents from contacting microbial cells on the metal surface.
After cleaning, sterilizing the shears kills lingering plant pathogens and prevents disease transmission. Isopropyl rubbing alcohol (at least 70%) is a highly effective, quick-acting disinfectant applied with a spray bottle or damp cloth. A 10% solution of household chlorine bleach (one part bleach to nine parts water) is another option, but the tools must soak for 10 minutes and then be thoroughly rinsed to prevent corrosion. A 3% hydrogen peroxide solution is also effective and does not require rinsing, as it leaves no corrosive residue.
Restorative Care: Dealing with Rust and Pitting
For older or neglected shears, corrosion removal is a more intensive task than routine cleaning and must be addressed before sharpening. Rust, formed by the oxidation of iron due to moisture exposure, can be removed through abrasive or chemical means. Simple abrasion with a wire brush or fine-grit steel wool can lift surface rust from the metal.
For established corrosion and pitting, an acidic soak helps dissolve the rust. Submerging the rusted metal parts in white distilled vinegar for 12 to 24 hours allows the acid to break down the iron oxide. After soaking, a scrub pad or toothbrush can easily remove the remaining rust particles. Once the rust is removed, the blades must be rinsed with clean water and dried completely to prevent flash rust formation, which occurs quickly on high-carbon steel blades.
Sharpening the Blades
Sharp shears make clean cuts. To sharpen the blades, secure the shears, often by clamping them in a table vise, to ensure stability. For bypass shears, typically only the cutting blade requires sharpening.
The correct sharpening angle, or bevel, for most hand pruners is generally between 20 and 25 degrees; maintaining this factory angle avoids damaging the blade’s geometry. Use a whetstone or a small mill file and move it in long, even strokes across the cutting edge, moving from the hilt to the tip. As you sharpen the beveled side, a slight ridge of metal, called a burr, will form on the flat side of the blade. Remove this burr by laying the stone flat against the back side of the blade and making one or two light passes.
Oiling and Proper Storage
Once the blades are clean, sterilized, and sharp, a final protective step involving oiling is required. A light machine oil, such as mineral oil or 3-in-1 Oil, should be applied to the blade surfaces to create a thin barrier that repels moisture and prevents new rust. Applying a few drops of oil directly to the pivot point and gently working the shears ensures smooth operation and lubricates the moving parts.
Linseed oil is an alternative non-toxic option that can also be used to coat the metal and any wooden handles. Proper storage is necessary to minimize moisture exposure, which is the primary cause of rust. Shears should be stored in a dry location, such as hung on a pegboard, or kept in a container of sand mixed with a protective oil, which keeps the blades dry and lightly lubricated.