Pretty picture: Calibrachoa 'Superbells Saffron'

Calibrachoa has been a problematic genus for us where I work, at least since I've been there. Last year, they all did okay up until a couple months into the season, where most of them suddenly and irreversibly yellowed (probably a mineral deficiency: iron was suspected but never proven). This year, we gave them a different fertilizer, on Younger Co-Worker's suggestion, one that had trace elements included (last year we were adding the trace elements ourselves, based on calculations from 2007, which obviously didn't work out right for some reason or another), and worked a slow-release iron product intended for lawns into the soil for the Calibrachoa and Petunia plugs.

And the, er, survivors look great, so that was a good idea too. But there was some confusion about how much of the slow-release product was supposed to go into the soil, on a day when I wasn't there, and so some of them got a lot more than they were supposed to and burned and died. So we have, now, a lot of some colors, and not so much of others, depending on who potted them up originally and how quickly the error was caught and the plants repotted.

But like I said: the survivors look great. (And the Petunias, which had similar yellowing problems last year, though not nearly as severe, look amazing: there's actually a lot of hand-wringing going on at the moment about how we're going to stunt their growth, because they're so huge and vigorous that we don't have room for them anymore, already, well before the gardening season even begins.)

So far, only the yellow Calibrachoa variety has bloomed, which is strange. These are marketed to us as being nearly interchangeable except for bloom color, but clearly the different varieties have different ancestries, with different ideas about timing and conditions and such. Not so much as a bud on the coral, red, blue, pink, or 'Tequila Sunrise' (a color-changing speckled variety which is variously orange, pink and yellow), but the yellow ones have been blooming for a couple weeks now.