Understanding galvanised steel: natural changes and normal ageing

The zinc coating and its natural change

Haws steel watering cans are protected by a zinc coating applied through galvanising. When the can leaves the factory, the zinc surface is bright and reflective. From that point onwards, it begins to oxidise naturally — forming a zinc oxide layer that actually provides the corrosion protection to both the zinc and the steel beneath.

This is not a fault. It's how the protection works.

What to expect as the can ages

As the zinc oxidises, the surface appearance gradually changes. The bright metallic finish mellows to shades of grey. If your can is exposed to regular wetting, this change typically accelerates. Water droplets can leave lighter or darker marks, and repeated wetting creates a mottled grey appearance. Over time with continued use, the surface usually darkens and becomes more uniform in colour, though some variation is normal.

Areas that you handle frequently — the handles, cross stays, or the upper spout — may gradually soften and brighten. This occurs through physical contact rather than chemical change, and is a sign of long-term use rather than a defect.

Paint chips at high-contact areas

If your can has a painted finish on galvanised steel, the same oxidation process occurs underneath. Paint may chip or scratch, particularly at the base where the can sits on hard ground, or at protruding edges like the handle, neck, or spout.

Where paint is removed but the zinc layer remains intact, the zinc continues to protect the steel. Even if both paint and zinc are removed through wear or impact, the surrounding zinc can provide limited protection to exposed steel until it is depleted.

Paint chips and worn edges are normal consequences of use. They do not indicate a structural problem or failure.

Surface marks and staining

You may notice areas of uneven appearance, marks where water has dried, or staining from mineral content in your water. These are all normal surface changes from exposure to moisture and handling.

None of these changes affect the can's ability to hold water or function in use. The protection remains intact.

What's not normal

Contact us if your can is leaking from the base or seams, if there are visible cracks, or if large areas of rust are visible beneath the galvanising. These indicate structural damage rather than normal surface ageing.