Vegetable-tanned leather is not a fragile material, but it does respond to how it is kept. A leather-covered book that is stored in a dry room, handled regularly, and conditioned once or twice a year will develop a patina that makes it look better at twenty years than it did at one. A leather book left in a damp drawer or on a sunny windowsill will crack and fade. The difference is small habits.

What vegetable tanning means

Vegetable tanning uses plant-based tannins, typically from oak bark or mimosa, to convert the raw hide into leather. The process takes weeks rather than hours, which is why vegetable-tanned leather costs more than chrome-tanned leather. The result is a firmer, denser leather that absorbs oils and develops a patina with use. It is the traditional material for bookbinding and it is what we use on all our leather-covered commissions.

Cleaning the surface

For light dust and surface dirt, a soft dry cloth is enough. For more ingrained dirt, a slightly damp cloth with a tiny amount of pure saddle soap worked into a lather will clean the surface without stripping the oils. Wipe off any soap residue with a clean damp cloth and let the leather dry naturally away from direct heat. Do not use household cleaning products, alcohol wipes, or anything with a strong solvent.

Conditioning: when and what

Leather needs conditioning when it starts to feel dry or slightly stiff. In most UK homes, this is once or twice a year. We use a small amount of Renaissance Wax, which is a microcrystalline wax used in museum conservation. Apply a thin coat with a soft cloth, let it sit for ten minutes, and buff gently. Neatsfoot oil is an alternative but it darkens the leather noticeably, which some people like and others do not. Avoid mink oil and petroleum-based products.

Storage and environment

Leather does not like extremes. A room that is consistently dry and warm will dry out the leather over time. A room that is damp will encourage mould, which appears as a grey-white bloom on the surface and is difficult to remove completely. Aim for a stable environment: a bookshelf in a living room is usually fine. Avoid windowsills, attic storage, and anywhere near a radiator. If you are storing a leather book for a long period, wrap it loosely in acid-free tissue.

What to do if the cover cracks

Small surface cracks in vegetable-tanned leather can often be stabilised with a thin application of leather consolidant, available from conservation suppliers. Deep cracks that go through to the board are harder to address at home and are worth bringing to a bookbinder. We assess leather damage as part of our standard repair service. Sometimes a cracked cover can be consolidated and retained; sometimes it needs to be replaced. We will tell you honestly which is the case.

Leather that is looked after properly is one of the most durable covering materials in bookbinding. A little attention twice a year is genuinely all it takes.