Why pans reward a little routine care

There is something deeply satisfying about opening a palette that is ready to go: pans sitting clean in their wells, mixing areas clear, a fresh sheet of paper within reach. Watercolour pans are essentially small cakes of pigment, gum arabic and a humectant such as honey or glycerine, pressed and dried. They are far more robust than many of us fear, but they have three quiet enemies: prolonged soaking, gritty contamination and damp storage.

The good news is that ten minutes at the end of a painting session is usually all it takes to keep a palette in working order for years. What follows is a practical routine that suits everything from a battered enamel tin to a wooden box palette kept on the studio shelf.

Everyday habits at the end of a session

The most important habit is simply not to walk away from a wet palette. Paint left standing in mixing wells dries in hard rings that lift as flakes into your next wash, and water trapped under a closed lid encourages mould.

• Tip away any standing water, then blot the mixing wells with a corner of kitchen roll rather than rinsing the whole palette.
• Wipe each pan lightly with a damp, soft brush or a barely moist cloth. You want to remove loosened pigment, not scrub the surface flat.
• Dry the rim and hinges of a metal tin with a cloth. Hinges are the first place rust takes hold, and a gritty hinge will eventually work loose.
• Leave the palette open to air for an hour or two before closing it. If you paint in the evening, leave the lid ajar overnight and close it in the morning.
• Never leave a wooden palette sitting in water. The wood swells, the joints separate and the varnish lifts.

How to clean a watercolour palette properly

A deep clean every few weeks keeps colours honest, particularly if you use strong staining pigments or work with cadmiums and ultramarines that can muddy one another.

Use lukewarm water and a soft sponge. A drop of washing-up liquid lifts stubborn pigment from ceramic and plastic, and a dedicated nail brush is useful for the corners of mixing wells. Avoid scouring pads and cream cleansers entirely: scratches hold colour, stain the surface and make future cleaning harder rather than easier.

If a plastic palette has taken on a permanent tint, soak it for fifteen minutes in a solution of one part white vinegar to four parts water, then rinse well. Do not use this on metal tins or painted surfaces, and never on wooden palettes. White porcelain and enamel palettes can be cleaned with a little bicarbonate of soda on a cloth, but treat chipped enamel gently, as the exposed metal beneath will rust.

Remove half pans only when you need to. Ease them out with a fingernail or a blunt palette knife, working from the edge. If pans sit in a metal tin with a white enamel interior, avoid levering against the enamel. Once the palette is clean, dry it upside down on a tea towel so water drains away from the wells, and leave it to air completely before reloading.

Reviving dried, cracked or reluctant pans

Cracks, shrinkage and a dull, chalky surface are entirely normal. A cracked pan still works perfectly well; the crack simply gives your brush an extra edge to pick up colour.

To revive a pan that has gone hard, add two or three drops of clean water and leave it for ten minutes. Resist the urge to flood it. Water sitting on a pan for hours softens the binder and turns the surface to sludge, and tipping the palette to drain will carry pigment into neighbouring wells.

If a pan is crumbly and will not hold together, a pinhead of gum arabic worked in with a damp brush will restore cohesion, while a single drop of glycerine or honey improves rewettability in very dry conditions. Add these sparingly, a little at a time. Overdoing it leaves you with a sticky pan that never quite dries.

Mould appears as a white or greyish fuzz and is more common in UK winters, when a palette sits in a cold spare room. Remove the affected pan, clean the well with a dilute alcohol wipe, and let everything dry thoroughly. If mould has worked into the pan itself, replace it rather than risk contaminating the rest of your colours.

Storing your kit between painting sessions

Storage matters as much as cleaning. Keep palettes somewhere dry and temperate, not in a shed, garage or conservatory where temperatures swing. A small silica gel sachet tucked into a storage box will mop up the damp that our climate generously provides.

Store a tin flat rather than upright, so half pans stay seated in their wells. If space forces you to stand it on edge, a rubber band around the tin keeps the lid from springing and the pans from sliding. Wooden box palettes prefer a shelf away from direct sunlight, which will dry and split the timber over time. Finally, keep a swatch chart of your colours with the palette. It saves guessing which pan is which when lids are labelled faintly or not at all.

Travelling and outdoor sketching

A small travel tin, a folded piece of kitchen roll and a water bottle are all you need. Wipe each pan before you close up, empty the water reservoir rather than carrying it home, and never leave a damp palette in a warm car: the heat encourages mould and can crack the pans.

Back at home, give the kit a full clean and an overnight dry before it goes back on the shelf. That one habit alone will keep your colours fresh, your palette sound and your materials always ready for the next sketch.