How hardy? Ours is a bit late.
Most of ours have flowered but the frost the other night had a very variable effect. Some plants seem to have suffered quite badly and others not at all. All came from the same Franchi packet. Good half inch of ice on top of standing water in backet.
Franchi broccoli same, some plants devasted and right next no effect. Think I might fleece them next time there is a frost forecast.
I meant to but was too lazy!
Romanesco certainly not hardy in Glasgow. Mine were all eaten a long time ago.
I only have three left on the plot. They don't seem to have been affected by the frost, but haven't produced a head either! ::)
I am leaving them to see whether they survive the winter and if so, if they will come to anything in the spring. It's doubtful, but I don't need the space for anything at the moment.