Using Madder Root and Water Only to Dye Alum Mordanted Wool

My companion and I stood on the doorstep, bracing ourselves to step out into the June rain drenching the garden.
"At least you won't have to water the pots, Beaut."
"I never water the madder barrels, those roots need sharp drainage. Mind, I don't know if that hot summer last year might have been too dry, even for madder."
"Well, you'll find out soon. Didn't you just use up the last of the dried roots?"

The remaining 100g of dried madder root from last spring's harvest had indeed been chopped in a food blender, covered with boiling water and left to soak overnight. In an attempt to replicate the success of my previous madder dye session, I followed the same minimalist process, simply adding more water next morning before putting in an equal weight of yarn mordanted in 10% alum. The pot was heated to more than hand hot but not boiling, kept hot for an hour, then left overnight. Despite the dye bath being naturally mildly acidic, the 100g skein of 4ply Falklands Merino/Silk blend came out a decent colour, though not as blood red as the alum mordanted skein of Blue Faced Leicester wool I dyed last week (shown balanced on top).

I had simmered the other half of that original skein of Blue Faced Leicester in the afterbath, just to see if the yarn itself might hold the key to success. Of course, there was less colour left in the dye bath for it to take up, but I do think it is somehow redder than the first. Apart from being a different kind of wool, I remember that that particular skein was among some that got neglected and accidentally left in a cold alum mordant bath for five days rather than two. It is dawning on me that the longer things soak in alum, the better they seem to dye, even though increasing the percentage of alum doesn't seem to make much odds. To exhaust the dye bath, two skeins of coarse wool yarn in pale shades of grey were heated briskly and left to fester for a couple of days before I poured the mouldy gloop onto the compost heap. By that time, it had fermented down to pH 5 and the yarn looked distinctly orange.

After we had walked the dog, I laid out the products of my two madder dye baths and sat back to contemplate them. Rain hammered on the skylight.
"Were those madder roots worth waiting three years for, Beaut?"
"Yes. I think so. I like all the colours and I'm a bit further forward with understanding the dye. Next time, I shall do an experiment dyeing yarn that has soaked in 10% alum for two days versus yarn soaked for five days."
"So, when you're dyeing with the roots you dig out of the next barrel, you won't be trying calcium carbonate or bran or rinsing the roots or changing the pH or the temperature?"
"Just adding water is good."
Elinor emptied her Wellington boot out into the sink.
"Not if you're a sock."