A neighbor gave me some fresh tarragon from his garden. I asked Google how to root it and got this:

To root tarragon, take stem cuttings, preferably from young, healthy stems, early in the morning. Cut stems that are 4 to 6 inches long, just below a node (the point where leaves grow from the stem). Remove the lower leaves, dip the cut end in rooting hormone (optional but recommended), and plant in a well-draining potting mix. Keep the soil consistently moist and provide indirect sunlight. Roots should develop within a few weeks.

I followed the instructions to the letter, except that the cuttings I used were a day or two old when I planted them. (They had been kept in a bag, mostly in the fridge.) And within a few weeks they turned brown.

I used potting soil. In addition to keeping the soil damp, I sprayed the cuttings with water once a day, and put plastic bags over them (loosely) to limit evaporation.

Is there a special trick to this? Something I need to do that Google missed?