Re: Some Fall pics of zone 4 Yucca
I'll also grow palms outside (4 Trachycarpus fortunei, 1 Chamaerops humilis) but if the temperatures are going down I'll need to protect them. Some Agaves remain out too but under a glas coverage. You're right, the daylight will be one of the differences, during winter we often do have gloomy weather (hope that describes it right) and no sun for some days. Actually I'll grow Sabal minor and will try one outside next spring on the hottest place of my garden.
Maybe also this one zone might be enough for better growth and much bigger survival chances of plants which are borderline in my area.
When travelling through SC and NC last year I saw so many palms, also a few needle palms but I only found seeds from Sabal palmetto and some Yucca in Kitty Hawk