How Do I Prep New Cloth Diapers?

By April Duffy •  Updated: 07/05/24 •  10 min read

After you’ve decided you’re on board with cloth diapers, bought some new ones, and taken a minute to marvel at their cuteness, it’s time to get them ready for baby.

So how do you “prep” [prepare] new cloth diapers for use? Most of the time, you can prep your new diapers with just a simple wash with hot water and detergent. That’s it. But there are a few circumstances where a few washes are needed, which I go into below.

Why Do I Have to Wash Them if They’re New?

You need to prepare cloth diapers for your baby by washing them for a few reasons, depending on what you’re prepping:

  1. Especially with diapers manufactured far away and shipped long distances in boxes and crates, you want to wash them to get any chemicals, dust, etc. off of them before putting them on your baby. As I like to say, you want to wash the manufacturer’s lunch off them.
  2. In the case of hemp, you want to wash the fabric several times before use so that the diaper is at its maximum absorbency when it’s on the baby. This will prevent cloth diaper leaks.
  3. To adhere to any manufacturer warranties. When a diaper is new and under warranty, you want to follow the directions that come with the diaper exactly, to avoid any situation where you have a problem with the diaper but they tell you that you voided your warranty so they won’t help you. It’s rare (cloth people are awesome in general) but why take the chance?

Wait, Don’t I Have to Wash All Natural Fiber Diapers a Ton of Times?

There is a lot of misinformation out there about how to prep new diapers, and some of it just doesn’t make sense. A lot of the misinformation has to do with prepping “natural fibers.”

I mentioned above that hemp needs special preparation, but you’ll often hear recommendations for multiple washes for all fibers believed to be natural, which include cotton, bamboo, and hemp. And I do mean multiple washes; sometimes to the point of insanity.

Take this example, which I read on a cloth diaper Facebook group I belong to, which is so extreme I had to take a screenshot because I don’t think anyone would believe me without it!

Note: I’ve blacked out people’s names for privacy purposes as this involves a real person out there somewhere who was not the poster of the comment.

This is so wrong, for SO MANY reasons, but let’s take a step back and look at each “natural” fiber to discuss how to prep it.

How to Prep Hemp Diapers

While it’s true that hemp fabric does need to be washed multiple times to reach its maximum absorbency, it certainly does NOT need to be washed 78 times, and even 7-8 times is pushing it.

I know from experience, as do many cloth diaper parents, that washing hemp not only makes it softer but it makes it more absorbent. Often in the cloth diaper community, this is said to be because of “natural oils” in the fibers, but outside of cloth diaper websites, I couldn’t find any confirmation of this theory.

With that said, I was able to find some information from Hemp Traders, who claim to be the largest supplier of hemp fiber products in the country, that might explain what we all know to be true.

As Hemp Traders explains here, “Because of the highly porous nature of the hemp fiber (i.e., magnified under a microscope it’s filled with lots of holes) hemp dries extremely quickly naturally (in the open air) or is easily tumble-dried.
“Each time hemp is washed it constantly reveals new surfaces, usually becoming softer with use. Given reasonable care it will render a lifetime of service.”

I usually recommend washing it 3-4 times before your first use, which will get it good enough for a small baby.

Hot water is great for hemp. As Hemp Traders states here, “Hemp generally will get softer with use and after each wash…. Another way to soften hemp is to do a hot water wash followed by a tumble dry, repeat these two steps two or three times.

Do I Have to Dry Between Washings?

I often get asked by those prepping hemp if they need to dry between washing cycles. As the quote from Hemp Traders points out, it can help soften the fabric, which in turn makes it more absorbent, so I do recommend drying in between washes.

As hemp is washed more and grows softer and softer, the absorbency will continue to grow, right along with your little one.

How to Prep Bamboo Diapers

Often, when talking about prepping natural fiber diapers, people will also say that bamboo fabric has natural oils in it just like they claim for hemp. This can’t be the case because bamboo is not really a natural fiber in most cases.

As the Federal Trade Commission explains here, “The soft textiles you see labeled ‘bamboo’ don’t contain any part of the bamboo plant. They are made from bamboo that has been processed into rayon using toxic chemicals.
“When bamboo is processed into rayon, no trace of the original plant is left… If a company claims its product is made with bamboo, it should have reliable scientific evidence to show it’s made with bamboo fiber.” (source)

For this reason, I recommend prepping bamboo inserts just as you would a synthetic insert, which as you’ll read below means washing once with hot water and soap.

How to Prep Cotton Diapers

Once again, I can’t find anything about cotton and “natural oils” outside of the cloth diaper space.

What I COULD find, was several references to washing cotton towels before their first use for absorbency. Several hotel suppliers, newspapers, and even Martha Stewart explain that many towels come with fabric softeners in them (making them nice and fluffy for shoppers) which inhibit their absorption. There’s also some reference to opening up the fibers of towels to maximize their absorption.

As Martha explains here, “Be sure to wash your towels before you use them, as this will open up the fibers. “If the fibers aren’t open they won’t be as absorbent,” says the team from Garnet Hill. New towels are often coated in fabric softeners so they’re nice and plush for shoppers, but these softeners prevent towels from soaking up water.”

Since cloth diaper makers know that absorbency is key they aren’t silly enough to put fabric softeners on their products, therefore washing once with hot water and soap is sufficient to prep cotton diapers.

How to Prep Microfiber Diapers (and other Synthetic Materials)

Microfiber inserts, charcoal bamboo inserts (which are most often microfiber wrapped in fleece), and the fleece or microsuede linings used in pocket diapers.

Synthetic fabrics don’t need any special preparation other than washing the manufacturer’s lunch off of them.

This is widely accepted in the cloth community, and proven by experience. Almost all of the synthetic materials used in cloth diapering are not for absorption, with the exception of microfiber (and charcoal bamboo), and my research into microfiber has found no special care instructions for microfiber other than making sure not to use fabric softeners of course and drying on medium heat or lower if you’re using a dryer to dry your cloth diapers.

This all means that washing once with hot water and soap is sufficient to prep microfiver and other synthetic diaper inserts and pocket diapers.

How to Prep Cloth Diaper Covers

Cloth Diaper covers are made from laminated polyester (PUL or TPU), elastics, and either velcro or snaps.

Just like all the polyester products included in the synthetics section, diaper covers can be prepped by washing once with hot water and soap.

How to Prep Wool Diaper Covers

Prepping wool is a whole different process, that requires lanoline and gentle hand washing.

For instructions, head over to my wool cover 101 post here.

Do I Need to Wash Everything Separately?

No, there is no need to separate inserts from covers, hemp from microfiber, etc.

There are two reasons people sometimes think they need to separate things when prepping diapers:

  1. Some cloth diaper blogs say that segregating synthetic (polyester) fibers is needed so they do not retain any of the plant oils from the natural fibers. But as we learned above, that’s unproven for hemp and wrong for bamboo.
  2. The directions that come with the diaper are super confusing (especially with diapers from China). They may say, ‘separate before washing’ or something, which is very confusing, but what is often meant here is just that you need to remove the insert from the diaper cover before washing, which is true.

One caveat: One thing you do have to do if you’re washing everything together is to make sure you’re washing and drying at a temperature that’s ok for synthetics or diaper covers, if you’re washing them with your natural fiber inserts.

Always default to the gentlest cycle needed for any diaper included in the load.

What Wash Routine Should I Use to Prep New Cloth Diapers?

When prepping your new diapers, you don’t need to use your regular cloth diaper wash routine, since this load of diapers will not be heavily soiled (ie. full of human waste) and dry. Instead, you can skip your initial rinse and lower your detergent amount slightly. Since this is only one wash, of relatively clean diapers, don’t sweat it too much.

How to Prep Pre-loved Diapers

As you can imagine, used diapers have their own special needs when it comes to getting them ready for a new baby.

I have written a full post about how to sanitize and prepare used diapers for your baby here, so go check that out for all your pre-loved diapers.


Ok, so let’s simplify all this; how do you prep new cloth diapers for use? Wash all of your diapers in hot water (but not boiling) with detergent to prep them. One wash and either line or tumble drying are needed for everything EXCEPT hemp. Hemp needs to be washed and dried in a dryer 3-4 times to reach high absorbency.

If you’re looking into prepping new cloth diapers, you’ll want to use a good cloth diaper detergent. If you’re not sure what a good cloth diaper detergent is, click here.


Can (or Should) I Boil my Cloth Diapers?

No. Seriously, do not boil your cloth diapers.

Boiling is not necessary for natural fabrics and will possibly melt some synthetic fabrics, snaps, and elastics.

While it was common back when diapers were basically flat (single layer) cotton sheets, cloth diapers today aren’t made to handle that kind of treatment, nor do they need to thanks to modern washing machines.

Can I Wash My Couple New Diapers With Other Laundry?

Yes. Go for it!

There are a few things to keep in mind, like making sure you use the right detergent, etc. Here’s some info on washing diapers with other laundry if you want to know more.

April Duffy

April is the founder of Cloth Diapers for Beginners and author of The Cloth Diaper Wash & Care Handbook. Since 2015, April has helped well over 75,000 parents and caregivers cloth diaper their children through this website, her book, her YouTube Channel, and the Cloth Diapers for Beginners Facebook Group.