How to get rid of mould on curtains and blinds

Published by Aurala Naturals. Last updated 2026.

To get rid of mould on curtains and blinds, take the fabric down and wash it, spot-treat any stubborn marks, and dry it fully in sun or moving air before you rehang it. Wipe hard blinds with a damp cloth and a natural cleaner. Then fix the real cause: window condensation and still, humid air trapped against cold glass.

Why do curtains and blinds grow mould?

Curtains and blinds hang in the one part of a room where mould has almost everything it needs. They sit against windows, and glass is usually the coldest surface in the room. On cool nights, warm indoor air meets that cold glass and the water vapour in it turns back into liquid, the same way a cold drink sweats on a hot day. That film of water runs down the pane and onto whatever fabric is touching or sitting near it.

Fabric then holds the moisture. Curtains, roman blinds and cellular blinds are absorbent, so they stay damp long after the glass itself has dried. A closed curtain also traps still air, creating a narrow pocket between the cloth and the window where humid air has nowhere to move. Mould spores are already drifting through every room, and they only need a damp surface and something to feed on before they settle and grow. Dust, fabric fibres and the sizing woven into the cloth give them plenty to feed on. If you want the underlying physics, it helps to understand how indoor air reaches its dew point and wets cold glass.

A few common situations make it far worse:

• Bedrooms, where everyday living adds water to the air overnight and the window stays shut till morning.
• Rooms that are closed up for days, so the damp air is never replaced with drier air.
• Heavy blockout curtains, which are dense and slow to dry once they take on moisture.
• Windows that are rarely opened, so condensation builds night after night.
• Fabric that hangs long enough to rest directly on a wet sill.

How do you clean mould off fabric curtains?

Fabric curtains can almost always be cleaned, as long as you treat them promptly and dry them properly. Work outside if you can, so loose mould spores do not settle elsewhere in the room, and wear gloves. Always check the care label first, because some linings and blockout coatings will not survive a hot wash.

1. Take the curtains down and shake or vacuum the loose surface growth off outdoors, using a soft brush attachment rather than a bare nozzle.
2. Spot-test your cleaner on a hidden corner, such as the underside of the hem, to check the fabric holds its colour.
3. Wash them. Machine-washable curtains do well on the warmest wash the label allows. For delicate fabrics, soak and hand wash instead of risking the machine.
4. Treat any marks that remain. A paste of a mild cleaner dabbed on the stain and left for a while lifts most surface discolouration, and repeating that is kinder to the weave than scrubbing hard.
5. Dry them fully. Sun and moving air are your best tools, and sunlight helps fade any leftover shadow. Do not rehang curtains while they are even slightly damp.

Be honest with yourself about badly affected curtains. Once mould has grown deep into the weave of an old or cheap fabric, washing may lighten the mark without lifting it out, and the fibres can stay weakened. If the staining is heavy and set, replacing the curtain is often the more sensible outcome. No cleaner keeps mould gone on its own anyway, so the point of washing is to reset the surface, then fix the moisture so it stays clear.

How do you clean mould off blinds?

Blinds vary a lot, so the material decides the method. The good news is that hard blinds are usually far quicker to deal with than curtains, because the mould sits on the surface instead of soaking in.

• Aluminium and vinyl venetians, and vinyl rollers: wipe each slat with a damp cloth and a natural cleaner, go over it again with clean water, and dry it. These are the easiest of all.
• Fabric roller and roman blinds: lower them fully, vacuum off the loose growth, then spot-clean the marks with a barely damp cloth. Avoid soaking, because the backing can warp or stain.
• Cellular and honeycomb blinds: vacuum inside the cells and spot-clean gently. Their folded structure traps damp air, so they tend to need the most attention.
• Timber venetians: wipe with a slightly damp cloth only, never wet, because water swells and splits the timber.

Whatever the blind, dry it fully in the open position with air moving past it before you close it again. A gentle natural cleaner suits this ongoing wiping well, and it slots into the same room-by-room mould routine you use elsewhere in the home.

What should you avoid when cleaning mouldy curtains and blinds?

A handful of common mistakes let mould walk straight back, or spread it around the room:

• Rehanging fabric while it is still slightly damp, which restarts the growth within days.
• Scrubbing dry mould hard indoors, which flicks spores into the air and onto nearby surfaces. Dampen the area or vacuum it first, and work outside where you can.
• Soaking timber venetians or the backing of roman blinds, which warps and stains them.
• Cleaning the fabric but ignoring the window, so the same condensation simply feeds the next patch.
• Reaching for straight bleach on coloured curtains, which strips the colour and, on porous fabric, often bleaches the stain pale while leaving the root growth behind.

How do you stop mould coming back on curtains and blinds?

Cleaning only buys you time. Curtains and blinds will grow mould again within weeks if the window behind them keeps producing condensation, so real prevention is about managing water and air rather than out-cleaning the problem. The single most useful habit is dealing with the moisture on the glass each morning.

Manage the condensation first. On cold mornings, wipe the water off the glass and the ledge before it can wick into the fabric, and check that no water is pooling on the sill. The painted sills and frames just below the fabric often grow mould first and then pass it upward, so keeping them dry protects the curtains too.

Then improve the airflow, because still air is what lets a damp curtain stay damp. Open the window for a while each day, leave a gap between the curtains and the glass instead of pressing them flat against it, and pull blinds fully up during daylight so the fabric can dry out. Running an extractor fan or opening the room up after showering and cooking lowers the humidity that feeds the whole cycle. For a whole-home approach to drying the air out, our step-by-step guide to stopping mould before it starts pulls these habits together.

Finally, keep the fabric off the cold surface. Tie curtains back so they do not rest against wet glass or a damp sill, choose lighter, more breathable fabrics for rooms that suffer badly, and wash the curtains in problem rooms each season rather than waiting for marks to appear. Against cold, south-facing bedroom windows and inside wardrobes on external walls, a little space and a little air movement make a big difference.

There is no product that removes mould once and keeps it away on its own, and anyone who promises that is not being straight with you. What actually works is the loop above: clean the fabric, dry the air, and keep a gentle natural cleaner on hand for the regular wipe-downs that stop growth taking hold again. First Light, our six-oil essential-oil blend, is not a cleaner. Clean the fabric and blinds first, then use First Light to help keep mould from settling back: run a few drops in a diffuser so the oils carry through the air and meet spores before they settle, or mist a few drops in water over hard surfaces you have already cleaned, like the sill and window frame. It works in the air and where it lands on a surface. Lab tested: 99.2% reduction in black mould on direct contact. If you would like the Australian-made system, our range pairs First Light with the waterless diffuser that runs it.