whats a z5 COOL porch ... that is the undefinable variable ...

give it a try ... what do you have to lose..

try rooting some... .. etc.. try various methods ...

ken

i sincerely hope I get some more answers.

Hi Flowergirl,If your porch is warm enough to keep other plants,like geraniums,for instance,you should be able to keep verbenas.I have a greenhouse & I used to bring in the Tapien Purple Verbena but don't anymore due to their being bug magnets.If you aren't bothered by insects,go for it.Just 1 plant,even if it kind of limps along in the darker months can be a source of many plants come spring.
Good luck,
Rose

you might get more answers.. if you define your porch ...

are we talking screens??

are we talking an insulated florida room on the south side ...

does it freeze at night..

is it heated...

is it on the south side ...

on a 5 degree z5/6 winters day.. how warm does it get..

and when it falls to zero that night.. how long does it stay temperate???

really ... what answers are you expecting.. when we have no real clue as to the room/structure you are talking about ...

we really want to help.. but what can we do other than guess???? .. please.. give us some facts ... upon which we can make an educated guess ...

which leads me back to.. give it a try.. what do you have to lose???

ken