Rhubarb root

Chopped dried rhubarb root.

Chopped dried rhubarb root.

Today, a rather obscure dye plant: rhubarb, specifically the root. Once I had heard about it, I had to try it, but first I needed to convince someone to uproot their rhubarb plant to supply the material. Fortunately, my mother obliged (dankje, mama!). She had two plants and agreed to dig up the larger of the two, since she wasn't going to eat that much rhubarb anyway. The roots were washed, chopped, dried and mailed to me. I received about 250g of dried rhubarb root bits. 

The material smelled very interesting and rather nice. Earthy and fresh at the same time, hard to describe. I first soaked it in cold water overnight, then simmered it for an hour or so before adding the fabric (mordanted with alum). The dye bath was a nice yellow, and that is the color I was expecting. Modifying with washing soda was supposed to turn it pinkish.

Fabrics soaking in the rhubarb root dye bath, with added washing soda on the left.

Fabrics soaking in the rhubarb root dye bath, with added washing soda on the left.

And that is what happened.  Again, a really interesting color shift through simple modification of the acidity level. In the above picture you can see the fabric after soaking for only a short period of time, so I was optimistic: longer soaking usually results in more intense color, so I left them overnight to see how they would turn out

Unfortunately, this dye did not behave as others. Even after longer soaking, boiling the plant material again to try to extract more dye and even longer soaking, the fabric stayed pale. But at least the colors were nice, right? Even a pale yellow and pale pink are good colors to have.

The two pieces of fabric in the front were dyed with rhubarb root, still wet in this picture

The two pieces of fabric in the front were dyed with rhubarb root, still wet in this picture

After drying the fabric, another disappointment: the colors had turned a lot less intense and more towards beige or brownish shades. There is still a visible difference between the two, which is nice, but overall, not the most interesting colors I've ever seen. At least they seem to be lightfast, which is more than can be said for some other dyes I've tried.

As always, these subtle shades were very difficult to capture in a photo. I'm sure I'll find a good use for them complementing some bolder shades or in a collection of other pale ones, but overall, I'm rather sorry that an entire rhubarb plant had to give its life for this experiment...

Alternating unmodified/alkaline rhubarb-root-dyed fabric. The bottom two bits of fabric were unbleached cotton, which is why they are a bit darker than the others.

Alternating unmodified/alkaline rhubarb-root-dyed fabric. The bottom two bits of fabric were unbleached cotton, which is why they are a bit darker than the others.