There is only a handful of medieval treaties that address the problem of moth control, a French one and two English ones. Not unexpectedly, their public was the upper classes rather than poor peasants.

Le Ménagier de Paris, anonymous, 1393

Titled in English The Goodman of Paris (1928), and more recently The Good Wife's Guide (2009), le Ménagier is a guidebook describing the proper behaviour of a young wife and the management of a bourgeois household. The Ménagier includes moral prescriptions for women, recipes, remedies, and various tips and tricks for running the household. All of this has made it a gold mine for historians, who have used it for countless studies on medieval life. Here is what it says about the prevention of cloth-eating moths in a rich household (translation Greco and Rose, 2009):

You and the Beguine [the wife's companion/governess], at the proper season, have your women air out, shake out, and inspect your sheets, coverlets, clothing, furs, skins, and suchlike. Be aware and inform your women that to protect your furs and garments, one should air them often in order to avoid moth damage. Since such vermin breed in the humidity of the fall and winter and the larvae hatch in the summer, air out the furs and other garments in the sun on fair, dry days. If a dark, damp cloud comes and descends on your garments and you fold them in that condition, this air enveloped and folded into your garments will engender worse vermin than before. For this reason, choose continuous dry weather. As soon as you see stormy conditions coming, before it reaches you, have your garments brought inside, shaken out to remove most of the dust and then cleaned and beaten using dry sticks.

Boke of Nurture, John Russell, circa 1460-1470

written by the "Usher and Marshal to Humphrey, Duke of Gloucester", this book of domestic economy is mostly concerned with food, but contains a few pages on the office of chamberlain (with notes about bathroom hygiene) and on managing his lord's wardrobes. Again, we're not talking about peasants. Here it is, written in glorious 15th century English:

IN þe warderobe ye must muche entende besily the robes to kepe well / & also to brusche þem clenly; with the ende of a soft brusche ye brusche þem clenly, and yet ouer moche bruschynge werethe cloth lyghtly. Lett neuer wollyñ cloth ne furre passe a seuenyght to be vnbrossheñ & shakyñ / tend þerto aright, for moughtes be redy euer in þem to gendur & aliȝt; þerfore to drapery / & skynnery euer haue ye a sight.

So: brush your clothes clean with a soft brush, and never let woolen cloth more than a week in a chest without being brushed and shaken out, otherwise the moths (moughtes) will breed (gendur).

Ortus sanitatis, Jakob Meydenbach, 1491 and The noble lyfe & natures of man, of bestes, serpentys, fowles & fisshes yt be moste knowen, Laurence Andrews, 1521

The first book is a natural history encyclopaedia written in Latin and published in Mainz, Germany in 1491. The second book is an English translation printed in London of the chapter of the first book dedicated to land animals (Tractatus de animalibus vitam in terris ducentium). Here is the relevant page of the Noble lyfe..., which shows a person looking sadly at her/his moth-eaten clothes. The Latin version is here. The "Moths" entry is shown between a woodworm and a bird-eating snake. Here is the text of the English version:

The Motte bredethe amonge clothes tyll that they have byten it a sonder / & it is a maniable worm, and yet it hydeth him in ye clothe that it can scantly be sene / & it bredethe gladly in clothes that haue ben in an euyll ayre, or in a rayn or myst, and so layde vp without hanging in the sonne or other swete ayre after.

The Operacyon. The erbes that be bitter & well smellinge is good to be layde amonge suche clothes / as the baye leuis, cypres wode.

The first part of the text contains more or less the same information and advice given in the Ménagier and the Boke of Nurture: moths naturally breed in clothes, notably when they are kept in damp conditions, and it is recommended to expose the clothes to the sun or "other sweet air". The second part introduces potential insecticides or at least insect repellents: bitter and good-smelling plants to be "laid among such clothes", such as laurel (bay leaf) and cypress wood. In the original Latin version, books were also protected: Knight (2016) notes that fragant plants were also used to protect books, which were increasingly made of recycled linen and thus targeted by pests.

The addition of plant-based insect repellents seems to have been more and more common starting in the late 15th century. As we enter the modern period, references to plants and plant products become widespread.

One piece of advice that appears reguarly from the 16th century onward is the following, written by Latin author Cato the Elder in his farming manual De agri cultura (circa 160 BC), which contains the following entry (translation Ernest Brehaut, 1933):

XCVIII. To keep moths from touching clothes (Vestimenta ne tineæ tangant). Boil [olive] oil dregs down to half and dress with them the bottom of the chest and the outside and the feet and the corners. When it had dried, put the clothes in it. If you do this, moths will do no injury.

Cato's recommendation appeared in several 16th century compilations of Roman books of agricultural husbandry, such as the De rustica published by Johan Gymnich in Cologne in 1536, and it would be repeated in numerous household manuals in the following centuries, like for instance in Thomas Lupton's A Thousand Notable Things of Sundrie Sorts (1631):

To keep cloths from moths. 94. If you seeth the dregs or mother, or foam of Oyle to the halfe, and therewith annoint the bottome, corners and feet of any Chest or Presse , the clothes, that you lay therein, Shall never be hurt with Mothes. So that it bee dry before you put therein your clothes

Over the years, numerous plants would be considered to be suitable as moth repellent.

Rosemary (Salvia rosemarinus Spenn.) in Banckes' herbal (1525), the first herbal published in England:

Take the floures and put them in a chest among your clothes or among bokes, and moughtes shall not hurt them.

Sumac (possibly the Mediterranean species Rhus coriaria L.) in An herbal for the Bible by Levinus Lemnius (English translation, 1587)

Like also and of kin to this wilde Myrtle, is another kinde of shrub or low plant, called Pseudomyrtus, of a pleasant smell and somwhat strong withall, whose leaves and wood being dried, are used to be laide in wardrobs and presses to perfume clothes and keepe them from Moths. Pseudomyrtus, called also Rhus, or Sumach.

Bog myrtle (Myrica gale L.) in The Herball Or Generall Historie of Plantes by John Gerard (1597):

The whole shrub fruit and al being laid among clothes, keepeth them from moths and wormes.

Wormwood (Artemisia absinthium L.) is often cited in the 17th century texts, such as the English Physitian, by the great botanist and physician Nicholas Culpeper (1652), who wrote this amusing and slightly philosophical piece:

I was once in the Tower [of London] and viewed the Wardrobe; and there was a great many fine Clothes, (I can give them no other title, for I was never neither Linnen nor Woollen Draper) yet as brave as they looked, my opinion was the Moths might consume them, (yea, Henry the eighth his Cod-piece.) Moths are under the dominion of Mars, his herb Wormwood, being laid among at Clothes will make a Moth scorn to meddle with the Cloth, as much as a Lion scorns to meddle with a Mouse, or an Eagle a fly.

Other plants cited in the 16-17th century European literature (herbals and domestic manuals) include cotton flowers, lemon powder, lavender, amaranth, "florentine iris" etc. The recommendation of taking the clothes out to hang and beat them in the sun was often repeated, and it could be found in compilations of religious metaphors and similes, such as the Storehouse of Similes of Robert Cawdry (1609):

As woollen cloth must be often beaten and brushed , lest moths breed in it: even so spiritual moths and worms - to wit, wickedness, sin , and abomination - have the less power to breed in us if we be well brushed and beaten in time with trouble, affliction, and adversity.

This short list of tips and tricks gives us a summary idea of how rich people could protect their clothes from vermins. The main piece of advice is simply to air the clothes frequently (weekly) and have them hang in the sun and shaken up. This was not a bad recommendation, considering that rich households had servants to do that, and not so many clothes compared to a modern one. Good clothes were expensive, and people took great care of them. Opening your clothes chest(s) once a week to make sure that there were no moths breeding there could have been a routine job, and less wealthy people, who had even less clothes, could certainly do that too. Starting in the late medieval period, people were told put a variety of fragrant plants - whatever they could find probably - in their clothes (and books) chests in the hope that they would repel the insects.

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