I noted Solanum pyracanthum on sale at nurseries in late summer, which makes sense for this heat-loving tropical from Madagascar. (Except when it’s not a heat lover, like at this moment in December when it’s thriving in my garden. What’s up with that?) Densely leafy and compact at the nursery in August, they were the antithesis of my one lanky, self-sown specimen at home, which I kept pinching back to encourage branching and more heft. Now the “Porcupine Tomato” is arching elegantly over a clump of Euphorbia mauritanica that just might bloom this spring, and I’m reconciled to its lanky ways. It’s won me over this December, a month when every effort made by the garden is appreciated. The low light catching the marmalade-colored thorns doesn’t hurt either. The solanum is one of those tender perennials (remember “temperennials?”) like the castor bean plant that ignores the seasons here in Southern California and can persist all winter. But unlike the raggedy castor bean, this solanum is actually looking pretty good. In summary, a tender perennial that wants the hottest spot you’ve got in your zone 7 summer garden is happy with the short days and cooler nights in a zone 10 winter garden. Which just goes to show that plants continually shrug off the rather arbitrary categories we assign them, like my happy-in-December Porcupine Tomato. Growing is knowing.