Some advice about wood care
Nothing lasts forever, but wood is tough stuff. With proper wood care, things made of wood will stay looking good indefinitely, and can improve with age. Kitchen ware has been made of wood for centuries, and people value antique bowls for their aged appearance.
Using a bowl
My bowls and other work have a moisture-resistant (but not waterproof) oiled finish. You can put a bowl to hard practical use and let it slowly develop a surface that reflects its history. Don’t put it in the dishwasher or keep it in the fridge. Don’t leave moist food in the bowl after use, and try not to let fruit go soft in the bowl, or it may stain. Use the bowl, hand wash it, and dry it quickly with a towel. Occasionally re-oil or wax it. Repeated over the years, this will give a bowl a patina that will become part of its charm. Friction from a dry towel will improve the surface shine and help get rid of any superficial water marks.
If you want to keep the piece in as-new condition, protect it from knocks and scratches. Don’t expose it to liquids, because water affects the finish. If you keep the bowl dry, it will need nothing more than perhaps an occasional rub with wax polish. Some wood species change colour slowly with time. Some fade, and others become darker and richer. Strong light will accelerate this, but no wood care will prevent it completely.
Refreshing the finish
If, in spite of your best efforts at wood care, the surface of the bowl becomes dull, you can apply further coats of oil to refresh or brighten the surface. If necessary, first wash the bowl with mild detergent to remove dirt and wax, and dry thoroughly. Then just follow the instructions on the can. I use a non-toxic, food-safe, plant-based drying oil such as Rustin’s Danish oil to protect the wood and show off the colour and grain. The oil penetrates the wood and hardens as it dries. It gives a durable finish that starts beneath the surface. It stands up to use very well, though contact with water may cause it to lose its shine. This is the finish I recommend for bowls that don’t have frequent contact with water. For ones that do, try mineral oil as suggested below.
The problem with wooden salad bowls is that oily salad dressings can soak in. No wood finish will prevent this in the long term. And non-drying vegetable oils such as olive oil eventually go sour. Clean the bowl immediately after use to remove oil and food residues and keep it fresh for as long as possible. Wash the bowl by hand, or if necessary scrub it with mild detergent, but don’t let it soak in water. Immediately dry the bowl thoroughly with a towel, and make sure the air can get to it when you put it away. The bowl will keep its attractive appearance, but with frequent washing it will lose its surface shine. A quick way to restore it is to wipe on a little food grade mineral oil similar to this product. It soaks in, but won’t go sour in the wood. It improves water resistance a bit, but it doesn’t dry in the wood. Oil near the surface will wash off with detergent, but can be reapplied as often as necessary. Because it stays liquid it can attract dust and dirt over time, so I only recommend it for bowls that will get washed often.
If food stains a salad bowl, the stains will slowly fade, or at least blend in with later ones.
You can remove scratches, superficial stains and small dents. Rub along the line of the grain with very fine abrasive paper, lubricated with finishing oil. Wipe off surplus oil before it dries. Some bowls are fragile, such as those with bark retained at the rim, and parts may break if subjected to rough handling. They can usually be repaired quite effectively with a little superglue.