Clothes Moths and Felting Wool: How to Protect Your Wool
We love working with wool because it is a natural fibre. Clothes moths like it too. They are simply doing what comes naturally, but their larvae can damage stored wool.
If you find moths amongst your supplies, you do not necessarily need to throw everything away. Here is how to check your wool and what to do next.
Is It a Clothes Moth?
Not every moth you see indoors feeds on wool. Two species to watch for in the UK are the common clothes moth, usually plain golden, and the case-bearing clothes moth, which has greyer wings with darker spots.
It is their larvae, not the adult moths, that damage wool. The larvae feed on keratin, a protein found in animal fibres.
What should you look for? Small, cream-coloured larvae, fine webbing between the fibres, little cases or damaged wool.
If you notice moths around your wool storage, check everything nearby.
Another clothes moth that can damage wool
The case-bearing clothes moth is worth knowing about too. Its larvae make little portable cases out of silk and fibres, so you might find a case tucked into your wool before you spot an adult moth.
These moths do not damage wool
Not every moth you find indoors is a clothes moth. The two moths pictured below do not damage wool. One feeds on stored food, while the other feeds on plants.
Pantry moth – does not damage woolIts larvae eat stored foods such as cereals and flour. Look for the two-tone wings.
These are just two examples. If you are unsure what you have found, the Natural History Museum has an identification guide.
Found Moths in Your Wool? Here Is What to Do
First, put any wool you think might be affected into a sealed bag, away from the rest of your collection. There are two useful ways to treat it without insecticides.
Option 1: Wash Your Wool at 60°C
Hot water is an effective way to kill clothes moths and their eggs and larvae. Wool does not felt simply because it gets hot. Moisture together with friction and agitation is what causes felting.
- Submerge the loose wool gently in water at approximately 60°C.
- Leave it for 20–30 minutes, keeping the water close to 60°C.
- Do not stir, rub or agitate the wool.
- Drain gently and allow it to dry completely.
If rinsing, avoid sudden changes in water temperature. Take care when handling hot water.
Some dyed wool may release excess dye into the water. This is normal with certain types of wool and does not necessarily affect the finished colour. Test a small amount first and wash different colours separately.
Option 2: Freeze Your Wool
Freezing works well for delicate fibres and finished needle felted projects. Seal the wool in a freezer bag and keep it at −18°C or colder for at least two weeks. For bulky loose wool, use smaller, flatter bundles rather than tightly packed bags, so the cold reaches the centre. Let the wool return to room temperature while still sealed to prevent condensation.
Do not forget the storage area. Vacuum shelves, drawers and corners thoroughly. Empty the vacuum contents into a sealed bag and put it in the outside bin.
How to Store Your Wool
Good storage makes a big difference.
- Use sealed containers. Plastic boxes with well-fitting lids are ideal.
- Keep wool dry. Never store damp wool in sealed bags.
- Check your collection. Pay particular attention to wool that has been sitting unused for months.
- Keep storage areas clean. Vacuum regularly, including corners and gaps.
- Check new wool. Particularly second-hand fleece or wool from unknown sources.
Two Types of Clothes Moth Monitor
Moth monitors use pheromones to attract male clothes moths onto a sticky surface. They are useful for noticing activity around your wool, but they do not treat eggs or larvae.
Cardboard moth traps (pack of 10) are single-use. Each one lasts up to four months; replace the whole trap when it is due, or sooner if the sticky surface becomes dusty or full.
Personally, I prefer these. They are easy to fold into shape and put in different places around the wool. They do not have an end-of-life indicator, so I write the date I put each one out on a little note. That way, I know when to replace it.
Reusable plastic moth monitor comes with a sticky insert lasting about eight weeks. Keep the plastic holder and replace only the insert when it is time.
I like that there is less to throw away. The end-of-life indicator is handy too, because it shows when the insert needs changing. We also sell the replacement sticky inserts in packs of two.
Cedar, Lavender and Moth Treatments
Cedarwood and lavender contain fragrant natural oils. Their scent can put some adult clothes moths off settling and laying eggs nearby, which is why people have traditionally kept them with wool and clothing. As the scent fades, any deterrent effect may fade too.
They are a useful extra precaution, but they do not kill eggs or larvae or guarantee protection. Sealed storage and regular checks are still the most important things.
We are adding these wool-storage accessories to The Felt Box:
- Cedarwood balls for boxes and drawers. Check the scent every two to three months. When it fades, lightly sand the wood or add a drop or two of cedarwood essential oil. You can keep reusing the balls.
- Lavender bags for wool storage. Check them every two to three months, or sooner if the scent fades. Squeeze the pouch gently to release more fragrance, then add a drop or two of lavender essential oil if needed.
- Wooden oil diffuser to hold a few drops of cedarwood or lavender oil beside stored wool. Top up when the scent fades.
These items are coming soon; we will add their links when they are ready to buy. Checking the scent every two to three months is our practical reminder, not a scientifically proven period of moth protection for these products. Let oils soak in fully, keep them off the wool to avoid marks, and keep essential oils away from children and pets.
When You Need a Moth Killer
For an established problem, our Acana Max Hanging Moth Control (2 Pack) is an insecticide treatment designed for enclosed wardrobes and clothing storage. Unlike a monitoring trap, it is intended to treat a moth infestation when used as directed.
⚠ Insecticide warning: Hanging moth killers release insecticide even inside closed wardrobes. Follow the pack instructions, keep away from children and pets (particularly cats), and dispose of used units as directed. Insecticides can harm other insects and aquatic wildlife if released into the environment. Never apply them directly to loose wool unless the label specifically permits it.
For loose wool, washing or freezing as described above avoids insecticides.
Our Experience with Carded New Zealand Wool
Here is something interesting we have noticed over many years of working with wool: we have never encountered moths in our Carded New Zealand wool range.
We suspect this might have something to do with the dyeing and processing. This range retains a little excess dye. When wet felting, you will notice some colour running into the water, although the wool itself keeps its colour.
We wonder whether these remaining dyes or processing residues make the wool less attractive to moths. This is only our own theory, not something we have scientifically tested.
We certainly would not describe any wool as moth-proof, but it is an observation we thought worth sharing.
Can You Still Use Wool After Finding Moths?
Often, yes! Once the wool has been properly treated, you can usually continue using it if the fibres are still in good condition.
Remove badly damaged sections and make sure everything is clean and dry before storing it again.
For more information, see English Heritage's advice on clothes moths. If you have questions about wool purchased from us, please get in touch.