For all the planning it involves, gardening is filled with blink-and-you'll-miss-it moments. Like short-lived blossoms and butterfly fly-bys. A Venus flytrap chomping on a housefly. Sometimes you just want to gush off the cuff about the taste of a fresh-grown radish to whoever happens to be listening. Which...

Shaped like a candelabra, our Euphorbia avasmontana is in bloom. But when we talk about the spectacle, we're not talking about the flowers (which are too small to be easily seen)—we're talking about the plant's cyathia. That is, the yellow flower-like structures that add flash to a...