How do you look after curtains without taking them down?

Routine curtain care comes down to a vacuum cleaner, a nozzle and three precautions. The right ones matter.

• Turn the power down. This is the point that matters most. A curtain is a light, unsupported, free-hanging fabric: at full suction it gets pulled into the nozzle, the weave stretches, and on a sheer voile it runs. Use the adjustment dial, or crack open the vent valve on the handle.
• A soft-bristle brush, never a rotary brush. A turbo brush snags the fabric and pulls threads out of a voile in a second.
• Always top to bottom. Dust settles downward, and the hem is where it collects. Starting at the bottom just re-covers what you have already cleaned.
• Both faces. The room-facing side picks up smells and grease from the room; the window-facing side picks up incoming dust and condensation. On a lined curtain, the lining is often dirtier than the visible fabric.
• One hand behind the fabric. Placing your palm flat on the other side gives the fabric something to press against, so the suction actually works instead of just deforming it.

On an embossed fabric or one with metallic thread, place a fine mesh between the nozzle and the fabric. You vacuum through it, with no direct contact.

Take the bottom of a curtain between thumb and forefinger and roll it. On a two-year-old Marrakech villa curtain that has never been maintained, you will feel grit.

The bottom hem is a perfect trap: it is a fold of fabric, often lined and sometimes weighted with a lead cord, sitting exactly where sand settles. Sand comes in through a half-open window, slides down the folds, and builds up in this fold, from which it cannot work its way back out on its own.

Three consequences, in the order they appear:

• Weight. A loaded hem pulls on the full height of the fabric and changes how the folds hang.
• Abrasion. Every time the curtain moves, the grains rub against the inside of the fold and cut the hem threads from within. This is why a curtain almost always fails at the bottom first.
• Staining. Sand holds onto condensation running down the glass. The combination produces the typical grey marks along the bottom of a curtain.

The move that fixes it: open the hem fold by hand and run the flat nozzle inside it, along the full width, once a quarter. It takes five minutes per curtain, and it is what nobody does. The bottom of curtains in a medina riad needs the same care, and more often: damp from the old walls adds to the sand.

It is the instinctive move, and it gives the impression that something has happened. In reality, it just moves the problem elsewhere.

Whatever comes out of a shaken curtain ends up suspended in the room's air. Some of it settles on horizontal surfaces — furniture, rugs, sofa seats — and some returns to the curtain within the hour. On a heavy curtain, the shaking also strains the hanging points: the hooks pull on the heading tape, and a pleated heading ends up deformed.

What works instead, in order:

1. Close the window before starting, so you do not push dust back into the fabric.
2. Vacuum as described above, slowly, section by section.
3. Open it right up afterwards, once the work is done, to ventilate the room.

One special case is worth noting: the vertical steam refresher. It relaxes the folds and works well on a pleated heading. It cleans nothing — steam does not extract anything — and it adds moisture to fabric that sometimes touches a damp window sill. Useful for shape, to be avoided as a cleaning method.

The curtain is clean, it slides badly, and it is dirty again within a few weeks. The cause is above it.

A track and its rail concentrate three deposits nobody goes looking for: dust that sticks to the lubricant on the runners, corrosion on metal fittings in damp rooms, and ambient grease film in an open kitchen or living room. This deposit falls back onto the top of the curtain with every movement, which is why the heading of a curtain gets dirty faster than its middle.

What is easy to do, once or twice a year:

• Run a dry microfibre cloth along the groove of the rail, over its full length.
• Clean the rings and runners one by one — a lightly damp cloth, dried immediately.
• Check the wall fixings and tighten anything that has worked loose. A track with play in it distorts how the curtain hangs and eventually pulls out.
• Never oil-lubricate. Oil captures dust and turns the rail into a black paste that stains the top of the fabric. If a rail is sticking, it needs cleaning, not greasing.

A bent rail or a fixing that has pulled out is a job for a fitter: better to have it put right before it gives way under the weight of a lined curtain.

The rhythm depends on exposure, not the calendar. Three scenarios cover most Marrakech homes.

Standard exposure, window rarely opened, upper floor: monthly vacuuming of both faces, the hem opened with the flat nozzle once a quarter, a deep treatment once a year.

Villa with open bays, ground floor, garden or a building site nearby: vacuuming every two weeks, the hem monthly, a deep treatment twice a year.

Open kitchen or a room where people smoke: the curtain acts as a vertical air filter and becomes the fabric in the house that holds onto a smell the longest. Deep treatment twice a year, and weekly vacuuming of the room-facing side.

One seasonal marker applies to everyone: after a chergui episode, the sandstorm wind deposits in a few days what a normal quarter brings. That is the moment for a full vacuum, hem included, without waiting for the usual rhythm.

And the best time for a deep treatment is just before the season when windows stay closed: that is when smells trapped in the fabric become noticeable, as explained in our guide to damp smells in fabric.

This is why a curtain is cared for on its track, and it is worth explaining in detail because it is counter-intuitive.

Differential shrinkage. A lined curtain pairs two fabrics of different composition, sewn together. When wet, they do not react the same way: one shrinks more than the other. The curtain does not shrink evenly, it buckles. Once rehung, it never hangs straight again, and no amount of adjustment fixes it without redoing the seams.

Shaped pleats. On a pleated heading, the pleats are formed, stitched and sometimes heat-set. Handled flat, they flatten out, and each one has to be reshaped by hand.

Length. Lose two to three centimetres over the height of a curtain and it no longer touches the floor — which is immediately visible in a room.

Taking it down in the first place. On a high track, that needs stable access and two people. It is the moment a rail comes loose or a ceiling gets damaged.

Treating it in place removes all four risks: the curtain is vacuumed on both faces, spot pre-treated where needed, then treated with vertical, low-flow hot-water extraction from top to bottom, with the water immediately recovered on each pass. It dries hanging, in its shape. It is the same low-moisture logic used on mattress treatment, for the same reason: whatever goes in has to be able to come back out.

This needs to be recognised for what it is, because no cleaning corrects it, and it would be dishonest to charge for a treatment while implying otherwise.

On an exposed façade, ultraviolet light attacks the fabric's dye. The degradation is progressive, directional and permanent: a lighter vertical band on the part of the curtain that stays exposed when it is open, a faded edge on the outer fold, one face paler than the other.

On natural fibres, UV also attacks the fibre itself, which becomes brittle and tears when handled — an old curtain that "turns to dust" when taken down was destroyed by the sun, not by dirt.

The practical distinction: a stain is darker, fading is lighter. A treatment can make the first disappear, never the second.

What slows the process: a lining — its primary function, well before light-blocking —, a blind or an outer sheer acting as a screen, and simply not leaving a curtain half-open in the same spot all the time.

Before a deep treatment, photograph the curtain open, in daylight: the faded band reads more clearly before than after, and you will know from the start what to expect from the cleaning. The rugs and sofas in the same room catch the same sand and follow the same calendar — see rug cleaning at home and sofa cleaning.