This is an excerpt from "Miller's Treasure or Not? How to Compare & Value American Quilts" by Stella Rubin, now out of print.
The question most frequently asked of an antique "How can I wash my quilt?" The wise advisor offers no single answer. Each quilt must be considered on the basis of age, fabrics, and general condition. In some instances, washing a quilt can do more harm than good. The quilt owner must maintain a fine balance between the risks of washing an antique quilt versus allowing stains to remain that may do continuing damage to the fabrics. Washing is not out of the question, but neither is it necessarily the only or best choice.
Under no circumstances should dry cleaning be considered for cotton or linen quilts. The process will usually not remove stains on these fabrics, and chemical residue may cause further long term damage. With silk, velvet, or wool quilts, on the other hand, dry cleaning may be the only cleaning choice.
Often, a quilt can be sufficiently freshened by airing it for a day. Ideally, this is done outdoors, away from direct sunlight. For several reasons, it is advisable to do this at least once a year. First, it offers the opportunity to examine a quilt for damage. Second, it necessitates refolding the quilt for storage. Creases can become permanent if the quilt is folded in the same way for long periods. Not least of all, airing a quilt that is usually stored presents an opportunity to enjoy it.
Surface dirt can be removed by gently vacuuming over the quilt. The nozzle should be placed several inches above the quilt; it should not be used directly on it. For greater protection, a fine, clean, mesh screening can be placed over the entire quilt. Vacuuming is the safest method for cleaning quilts with glazed fabrics or with materials that are not colorfast.
The demands of washing an antique quilt defy generalization. An esteemed colleague, Xenia Cord, when asked advice about cleaning a quilt, replied "When one feels the need to wash one, the best thing to do is to lie down until the urge passes." Many people do wash their own quilts, but they face inherent risks in doing so. Dyes were not always as stable as those to which we are accustomed today. In addition, it may be close to impossible to determine the conditions to which the quilt has been subjected and how they will affect wet cleaning. The earlier the vintage of the quilt, the more unknowns exist. When done without sufficient care and knowledge, wet cleaning can cause tremendous damage. If your quilt is of great sentimental and/or monetary value, you may be better served to err on the side of caution. Consult a local museum to locate a professional conservator who has the facilities and expertise to do the job properly.
Should you decide to wash your quilt, you will first need to test each fabric in it for colorfastness. Use water from an eyedropper to wet the fabric. Blot it with a soft white cloth. Only if no color shows on the blotting cloth is it safe to proceed with wet cleaning. Use a gentle washing solution in warm water.
Machine washing is not recommended. Ideally, you should wash a quilt in a vat large enough so that the piece can be laid out flat- this usually means washing the quilt in a bathtub. Even so, you'll probably have to fold the quilt, which makes it cumbersome to rinse. It is not uncommon to have to rinse it as many as half a dozen times to remove all of the soap. Removing the quilt from the tub requires support beneath it. The weight of the water makes the quilt very heavy, and the fabrics may incur damage if not properly supported. For the same reason, experts advise against hanging the quilt on a line to dry. It should be laid out flat and blotted above and below with clean cloth towels. Fans can be helpful in drying the quilt more quickly. Never place an antique quilt in a dryer.
Light is one of the greatest enemies of textiles. It can cause the fibers to break down and fade- -both irreversible forms of damage. Natural ultraviolet light is the most damaging, but even long periods of artificial light, particularly fluorescent, can do harm. For maximum protection, quilts, like all textiles, need to be kept in moderate temperatures and humidity. Avoid storing them in the basement or the attic. Too much humidity can cause the growth of mold and mildew. Silverfish and other insects thrive in damp areas. Too hot or dry an environment can cause fabrics to become overdry and brittle.
Quilts should also be stored with as few folds as Possible. One of the best ways to avoid unnecessary folding Is to roll the quilt around a cardboard tube that is at least 3 inches in diameter and several inches longer than the quilt. The tube should be covered with acid-free tissue paper or a well-washed sheet of cotton or muslin upon which the quilt is then rolled with the top facing inward. This minimizes the strain on the stitching.
If the quilt must be stored folded on a shelf, in a blanket chest, or in a cardboard box, take care that the fabric does not touch the wood or paper. These materials contain acids that can stain the quilt. Again, several layers of acid-free tissue paper or a washed sheet of cotton or muslin provides excellent protection. Sharp creases are best avoided by crumpling acid-free tissue inside the folds to round them out. Do not stack many quilts on top of each other, for their weight can also create sharp creases. Commercially available acid-free boxes easily provide separate storage for each quilt.
A spare bed is one of the best places to store an antique quilt. Place it fully open on the bed, either pattern-side down or up, and cover it with a sheet to avoid exposure to light. The mattress provides even support and makes it unnecessary to fold the fabric.
Sealed plastic bags are to be avoided at all costs. They prevent fabrics from breathing and can trap harmful moisture. While moth balls are helpful in preventing insect damage to a wool quilt in a sealed blanket chest, care must be taken to make sure that the mothballs do not come in direct contact with the fabric.
In sum, the greatest enemies of quilts are light, extremes of temperature and humidity, and bugs. All can be avoided with minimal care and cost to lengthen the life of your antique quilt.