Here and there I dye with avocado stones. The pinks they give as well as the greys when dipped in iron water are simply stunning and a joy to use up something that would just be put in the bin. I’ve convinced a few my friends to save me their stones as I don’t eat nearly enough avocados for regular dye baths.
I thought I’d write down my dye ‘recipe’ as I’ve shared it a lot amongst dye friends and it has yet to fail me in achieving pinks. In no way its a bullet proof method, but seems to work for me.
I always freeze my avocado stones. I used to dry them, but had some problems with them shrivelling up 8and loosing colour. I use about 10 stones per 100g of yarn. No science to why, but this seems to give a good shade and a good colour for a 2nd dye bath also. I put my frozen stones in water and simmer these for an hour in about 80 degrees. I then leave my bath to cool. I add a bit more water to the pan and repeat the process and then I leave the dye bath to cool down again. If I dye a small amount of yarn, I leave the stones in as I add my yarn, but with larger quantities I strain the bath to remove the stones.
I don’t mordant my yarn when dyeing with avocadoes. The tannins in the stones act as a natural mordant and fix the colour in the fibre. I simmer the yarn for an hour and then leave it to cool in the bath, sometimes until the next day. You can modify the colour with iron water. The pinks turn to purpleish greys.
I have never done any colour fastness tests on avocado dyed wool, but I have knitted up garments dyed with them that have stayed a great colour even after continous wear. At the same time I’ve seen some avocado dyed fabrics loose their colour completely, but its difficult to know why, not knowing how they were pre-treated before dyeing. I am now going to pop a skein in the window and will see what happens after continuous exposure to sunlight
Update: 4th March 2019
I have had a skein of avocado dyed super wash merino wool in the windowsill for two months. My windowsill gets the sun most of the day and even in the winter the temperature rises quite high wilting my plants whenever the sun is out.
There is not much chance to the original colour after exposure to sun. The colour seems slightly darker and peachier than the original skein (see photo below). This is a positive sign! I might repeat the test in the summer and see if the strentgh of the sun makes a difference to the colour.