Here I will share my experience which I have gathered over many-many years of collecting all sorts of vintage dresses (and not just!).
I will try to keep it simple and easy to follow.
STORAGE
1. Direct sunlight is not good. This means that leaving your wardrobe open when a shoulder of a dress is sticking out is not a good thing to do - it might fade.
2. Keep moisture away.
This is not an easy task but there is a good solution - if you do not wear some dresses often, fold them nicely and put them in a thick paper bag which should be closed properly.
The paper bag should go into some sort of a container where moisture cannot get into, a big plastic box would be great.
3. No accidental chemicals - once I washed the floor and a few drops of water with the floor polish got into a fantastic silk gown and the fabric lost its color on the places where the water got to. Was a good lesson for me to learn!
4. No pets hair or food/drink stains. It is a natural process when organic things are taken apart by tiny organisms, this way Nature recycles us all :) and in order to keep your dresses away from this process for as long as possible make sure that they are free of pets hair (which contains attractive bits for the amoebas) and food stains. If amoebas find something yummy on your dress they might get carried away and eat a bit of fabric as well.
5. Keeping dresses tightly close to one another could result in color transfer.
6. Avoid using hangers for most of your beauties - the shoulders can stretch to an irreversible (and not pretty) state. The safest way - a nicely folded dress on a shelf (hanging shelf closet organizer is a good option).
7. A pouch with dried lavender is the best choice to keep moth away from your woolen dresses. Have several of those in your wardrobe - they last for months (at least). You can use chemicals but inhaling them is never good for a human or a pet.
8. If you have babies in the house make sure that they cannot get to your vintage beauties - babies love trying most fragile dresses on, running around in them and leaving a handful of tears in the fabric.
9. Our adorable pets. Once I was visiting a friend of mine and later it turned out that her lovely dog made himself comfortable sleeping on my extremely rare vintage coat for the whole evening. It took me several hours to clean the coat off hundreds of hairs and dry-cleaning had to be done to get rind of the dog smell. BTW, my coat was chosen over tens of others - the cute doggy had a very picky taste :)
10. Time to time dresses should be taken out of storage and left on open air to refresh for several hours (just avoid direct sunlight).
CLEANING
1. Silk jersey should be always dry-cleaned - this is done to avoid color bleed and loosing the shape of the dress as it might stretch unevenly.
2. Vintage prints on poly can still have color run while being washed so the very best way I found to clean them is to wash them by hand with a bit of gentle liquid soap and some sort of chemical to prevent color transfer, then rinse very-very-very well until the water becomes completely clear, then get rid of the water excess (large towels are the best) and dry outside on a sunny windy day. Phew, that is not easy but doable! And you will not have to do it every time, most likely once just after the purchase.
P.S. Bright acid colors will most likely run and might transfer to other parts of the print - so fast hand washing, proper rinsing and quick drying should do the trick. If not sure - dry-cleaners then!
3. Not all silks and wools must go to dry-cleaners (but it is preferred option unless you have a dryer and a special chemical to do the same at home).
Search the internet for "home dry-cleaning", you might be surprised how much money and time you can save. Don't forget to follow the instructions :)
4. Stains. Most of the stains come out to more or less degree, but some will not. Even after you have tried all possible methods. Consider dying. Modern dyes are easy to use (just follow the instructions without being too creative!) and also the pain of dying poly is no longer with us, there are new products that make it easy and cost under 5 dollars.
5. If you have to take a stain out try to do it with a piece of cotton wool or a soft cotton cloth, rub the stain gently as vigorous rubbing can result in a hole in the fabric - no, we don't want that.
5. Sometimes body smells seem to be impossible to take out, even with the best chemicals on the market. Try a simple method - dissolve several table spoons of plain white vinegar in a bucket of water and soak your dress in it for a few minutes. Then rinse and dry. Two or three rounds will take care of the hardest cases but usually one is enough for most.
6. If possible try to avoid using the washing machine as the spinning might get your dress out of shape. If you must use it then spin the dress wrapped in a thick towel or two.
7. Fabric softeners do cause color to run.
IRONING
1. Get yourself an iron shoe - the best invention for irons ever! You can then iron anything without leaving shiny marks, I never use my iron without one. Try to buy a quality one as cheapies might have little bits of plastic sticking our and this can cause snags. Also, don't forget to take it off time to time to clean off accumulated dust.
2. Glossy silks tend to get water stains if water is sprayed on them during ironing.
3. I use a spraying bottle which I fill with water and a drop of essential oil for deodorizing.
4. A sleeve ironing board is a great helper.
5. Most dresses are ironed the best when just a little bit dump.
6. Have a spare ironing board cover as there is a tiny possibility of dye transfer during ironing a dress and you will not want to risk to transfer this color to another dress!
MENDING
1. Bonding iron-on tapes are wonderful!
2. Minor alterations can do miracles, consider them if you have exhausted all possible options to keep the original state. And the best is to have it done by a professional unless you are just as good yourself :)
3. The hardest mends are moth bites and holes on knit wool. So the very best option is to keep to nasty insect away!
4. Runs and ladders in jerseys should be taken care of as soon as found - otherwise they might become larger. Invisible mending iron-on is great. The same is the best option for holes in chiffon.
5. Appliqués, matching buttons, ribbons and all sorts of embellishments can cover visible repairs.
6. Spare fabric from the inner seams can be used for patching.
7. If you have to do some mending, try to stay away from washing as washing can make the damage worse. Mend first - then wash.
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I hope that at least a bit of this information will help you to enjoy your beauties longer!