I love natural dyes. It's always an adventure. You never know exactly what color you'll get even if it's a dye stuff you've used before. So many things influence the color you get in the end. Where was the plant grown? Was there a lot of rain that spring or not much? Was it a hot summer or cooler than normal? When in the life cycle of the plant did you pick it? After it flowered? In the heat of the summer or the cool of autumn? Everything will influence the color you get in the end. Did you walk away and let the dye bath come to a complete boil? Which mordant did you use and how much did you use? Where you happy the day you dyed or was it a Tuesday? OK. The last two don't really matter but you get the idea.
All of the yarn I'm using for natural dyes right now is a super wash Merino wool that has been mordanted in Alum. I didn't do the mordanting myself but bought the yarn from someone who had prepared for a huge project that got canceled. I bought quite a few skeins from her and have been working to get it all dyed. The mordanting was done several years ago which is another factor that may or may not influence the final colors.
Lichen - I used tree lichen that was sent to us by some lovely ladies from Louisiana several years ago. I've lost their names but they were delightful and very kind to send us dyes stuff they had carefully collected. Tree lichen is abundant in this part of the world and not in any danger of being eradicated by enthusiastic dyers. Rock lichen and ground lichen which grow in more northern climes are in serious jeopardy of being over collected so be very careful or better yet don't collect it at all. My batch of lichen was stewed at barely a simmer for a couple of hours and left to sit for several days before I strained out all the hard parts and threw in the yarn. Again it was simmered for a couple of hours and left to cool down and sit for another couple of days. Here is the color I got. It's a nice warm beige but not at all remarkable.
Logwood - I used a bag of Logwood sawdust and chips that came from my friend Kate Weinheimer. Kate is a remarkable and talented weaver, spinner, dyer - an all around talented and creative person - who moved to a retirement community in California to be closer to her daughter. She sold a lot of her stash of fiber, yarn and dyes before she left Texas and I was fortunate to pick up some of her treasures. I don't know how old this Logwood was but I dumped all 5 ounces into a knee high stocking and dropped it into the dye bath. Logwood is a fugitive - it isn't permanent and will fade in the sunlight and/or with washing. But it sure gives a great purple color! We used it several years ago and I have one skein left that has faded to a lovely purpleish grey. It's not as strong a color as the original purple but still beautiful. In this case, the stocking full of Logwood was tossed in the dye pot and simmered for an hour or so. The yarn was added and allowed to simmer for another hour. The pot was left for a couple of days to cool and sit before the yarn was pulled out. This picture doesn't show the dark purple very well - in places its almost black.
Navajo Carrot - I used an unmarked bag of woody looking chunks for this dye bath. Peggy knew it was Navajo Carrot when she looked at it and I agreed. We simmered it slowing for several hours then strained out the dye stuff and added the yarn. We simmered it for another couple of hours and let it cool and sit for several days before we pulled out the yarn. We got a great gold color.
As I said, so many things influence the final color that your mileage may vary.