Sharp for as long as you own it.

Most of what keeps a knife sharp happens in the thirty seconds after you finish cooking.

Rinse the blade under warm water with a soft sponge and a drop of washing-up liquid. Wipe from the spine towards the edge, never along the edge with your fingers wrapped round it. Dry it with a towel and put it away. Leaving it wet in the sink or on the draining board is how knives meet other metal, and how they get knocked.

All of our blades are stainless, which forgives a lot. Stainless still means stains less. Acid from citrus, tomatoes and onions can mark the steel if it sits there, so when you are cutting them, give the blade a wipe between jobs.

The dishwasher is the one hard rule. The heat and detergent are hard on the wooden handle, and every knock against the rack takes a little off the edge.

A small upgrade. Linen is absorbent and dries quickly between uses, which is what you want from the towel that dries your knife. Our stonewashed linen tea towels are heavyweight European linen, made for exactly this job.

A Japanese edge is thin and hard. That is why it glides through a tomato, and why it dislikes anything harder than itself.

Glass, marble, slate, ceramic plates and stone worktops are all harder than the steel, and they dull an edge in days. Wood gives a little under the blade and closes again behind it. Aomori hiba, the Japanese cypress long used for shrines and temples, is just soft enough to spare the edge. Walnut sits close to it: firm enough to last for years, forgiving enough for a thin blade.

Let the knife do the work. Push it forward or draw it back through the food rather than pressing straight down. Keep the blade upright. Twisting or levering, through a pumpkin or a block of hard cheese, puts sideways force on a thin edge, and that is how chips happen. Bones and frozen food belong to a cleaver.

One habit worth breaking: sweeping chopped food off the board with the edge. Turn the knife over and use the spine. Scraping with the edge rolls it over, a little every time.

A loose knife in a drawer meets every other piece of metal in it, every time the drawer opens.

A magnetic stand or a wall rack keeps the edge touching nothing at all, and keeps the knife where you can see it. Put the knife on spine first and then lay the blade flat. To take it off, roll the spine away from the wood first, so the edge never slides across the surface.

If a knife has to live in a drawer, give it a wooden sheath or an edge guard, and keep it on its own.

Our magnetic knife stand and wall racks are made in solid wood with the magnets hidden inside, so the blade rests flat against the wood. Both are covered by the same lifetime guarantee as the knives.

Every Oishya knife arrives sharp. With daily cooking you will feel that fade over a few months.

The signs are small. The tip skates on a tomato skin instead of biting. Onions crunch rather than part. Herbs bruise. That is the moment for the stone, well before the knife feels blunt.

Leave the honing rod in the drawer. Rods are made for softer European steel; Japanese steel is too hard for them, and a rod is more likely to chip the edge than straighten it. A whetstone takes off a tiny amount of steel and builds a fresh edge, and it is easier than it looks.

Your first session, step by step.

Knife School walks you through it properly, over a few short emails. Start Knife School.

Our handles are made by hand in Poland, from stabilised maple burl and bog oak.

Stabilising fills the wood with resin, so it copes with a damp kitchen far better than raw wood would. It still likes to be dried after washing, and it still dislikes a long soak.

Every so often, put a few drops of camellia oil on a soft cloth and work it into the handle. Camellia is the traditional choice in Japan; food-safe mineral oil works too. Leave it ten minutes, then wipe off the excess. Avoid cooking oils, which turn rancid in the grain.