Wool Vs. Cotton: What it Takes to be a Summer Fiber
Or, Do I have to start using cotton now that the season has changed?
I apologize for not posting last week. I was recovering from an awful respiratory cold and decided to take my own advice (see my last post) for once!
I am almost exclusively a wool and acrylic yarn girlie. It’s what has been readily available to me in stores and has given me the best knitting/crocheting experience. But neither are considered “Summer” fibers. Acrylic definitely is not humidity friendly — plastic doesn’t breathe.
But wool breathes and it has moisture-wicking capabilities. It’s these very characteristics that make it beneficial in both warm and cool weather! So why isn’t it considered a “Summer” yarn?
One way to find out is to see what makes cotton a Summer yarn and compare the two fibers. According to a Textile Fibers booklet by Cotton Incorporated I found a pdf of online, cotton has a few unique characteristics that lend it to humid weather.
One such characteristic is that cotton fibers actually get stronger when wet. This is why it is such a great yarn to make items like dishcloths, towels, and bathmats. It also absorbs moisture at rates of 24% - 27% (of its weight) in extremely humid weather1. Which makes it rather moisture-wicking when worn as a garment. I also learned that mercerized cotton is stronger than non-processed cotton.
As this resource was created by “Big Cotton” (if you will), it didn’t have much information on wool and other protein-based natural fibers. It did spend much more time on manmade fibers and many different ways that is made, but that wasn’t the comparison I am trying to make. I went looking for some more information from a less cotton-biased source.
I found some from “Big Wool” (if you will), or American Wool a division of the American Sheep Industry Association, Inc. I figured if I could use one biased source, why not use an equally biased source from the “opposing” side?
Of course, that’s not to say that we must pit wool and cotton against each other at all times. But I am trying to compare and contrast the two fibers’ characteristics, so I’m not really sure what else I could use to label each side.
Anyway, what I learned was that wool (of undefined origin, so let us assume sheep wool) can absorb up to 30% of its weight in moisture2 — which is very close to what cotton can do. Interesting. This source was explicit in saying how wool uses moisture from both the body and the environment to help regulate temperature:
Wool always absorbs moisture from the atmosphere of greater humidity and releases it to the drier environment as it creates a balance in moisture conditions. This characteristic makes wool a versatile all-season fabric. Wool absorbs perspiration; thus it keeps a layer of dry air next to the skin which, in turn, helps to hold in body heat. As wool absorbs atmospheric moisture, the hydrogen bond of water is broken and chemically reacts with molecules of the wool to generate heat. … The same principle of moisture contact on the skin acts to protect against hot weather as well. The body cools itself naturally with the evaporation of perspiration. Wool expedites this process by absorbing perspiration and keeping the same dry air next to the skin. This is why wool clothing is worn throughout the desert regions of the world where it’s hot during the day and cool at night.
— American Wool3
But what if the atmosphere of the body and the atmosphere of the environment one is in is of similar humidity? Here in Maine, the heat from the Summer is always worsened by high humidity levels. We don’t have a dry heat like those who live in a desert. That wasn’t made clear and frankly, I didn’t find a whole lot of information about that scenario.
I will admit, I did not research this as thoroughly as I would a paper for a college class or writing a whole book on cotton versus fiber (despite my citations). But what I gathered from the many online articles I read through and videos I watched, was that people typically use terms like “cozy”, “warm”, and “insulating” when describing wool even while talking about the moisture-wicking properties and how great it is at keeping you dry when you sweat. Conversely, for cotton, terms like “cool”, “light”, and “breathable”. So I feel that, for the most part, wool being a “Winter” fiber and cotton being a “Summer” fiber has to do more with peoples’ preconceived notions of each fiber. It is a societal thing that stems from influence from the fashion industry and (in the U.S.) the cotton/wool industries.
I am currently making my Tolsta Tank (designed by Rebecca Clow of Creabea Designs) in a wool yarn. This is something that isn’t recommended for Summer knits. Since I ripped out the Wide Leg Shorts (by KnitCroAddict) and have my Lindy Chain (Knit Picks / We Crochet), which is recommended for Summer knits, waiting for a new project; I may just make another Tolsta Tank to compare the wear of the two fabrics.
Now that’s comparing a wool/nylon blend to a cotton/linen blend, rather than comparing straight wool and cotton to each other. But those are the yarns that I have already, and would get regardless to make garments out of. I don’t typically by 100% cotton to make a garment in. That is reserved for small projects like dishcloths, where I can finish them quickly and move on to softer experiences.
I think this real world experiment will help me better understand why cotton in the Summer and wool in the Winter. There’s nothing like first hand knowledge of how a fabric feels against the skin in humidity to help one understand which will be more uncomfortable than the other.
This is where a more industrious knitter would say, “If I were you I would subscribe to see how this experiment turns out!” But I know my creative flows and there is no way that I will finish both this Summer in time to find out which is the more worn tank top. Perhaps at the end of August 2026 there will be a post detailing which one I wore more that summer. But until then, I make no update promises.
What are your thoughts and opinions on what makes a fiber a “Summer” or “Winter” fiber? What is your preference?
I’ll see you at my next post,
Katie
I’m actually making a summer top in stripes currently, one stripe is a brown in cotton acrylic and the other is an ivory in wool acrylic. In a loose crochet stitch. I was thinking that might be good for a summer evening
at the beach.