From the pattern:

“And how, you ask, can drinking tea be dangerous? With
symbolism, of course. Unless your pot, like ours, is filled with Long Island Iced Tea rather than the steeped tea leaf kind.

“The dainty tea cosy is ornamented with flowers and berries of Belladonna, otherwise known (with very good reason) as Deadly Nightshade. The table mat illustrates the well-known principle “leaves of three, let it be!” This is the classic reminder to beware of poison ivy, poison oak, poison sumac. When a plant has three leaves, do not touch. It is dangerous!

“The tea cosy and table mat are crocheted from a size 3 acrylic or cotton thread. I used acrylic because my source was barren of any bright white cotton in an appropriate thread. Based on that experience (which made me dangerously angry at times), I heartily recommend using cotton because it is faster and easier to crochet. “

Crocheted edging is optional.