A long spell of deep cold knocked back the last of my greens and there’s a fairly even layer of deciduous leaves covering the ground, punctuated by bare limbs and decomposing stalks. My garden is pretty much hibernating. But one of the bright points this time of year is my thyme, which looks sprightly despite the January gloom. Herbalists like to play around with lists. Example: if you only had three herbs to work with, which would you choose? Thyme is consistently on my lists. It’s incredibly...