After several attempts, and numerous sticks stuck in trenches in the ground and pots indoors and out, I now have, to my astonishment, precisely one cutting of my Black Mulberry growing in a pot indoors on the windowsill. It has one leaf, which is growing from the node nearest to soil surface. The rest of the stick above it looks fairly dead. There are a couple of small buds coming from the old wood near the leaf base, where I am expecting some more growth.

Having got this far, and with only one, I don't want to mess it up. What do I do next? When would I transfer it outside and pot it on?