Ask Mr. Smarty Plants

Last question first, electricity stuff is WAY our of our line. We try to ignore electricity altogether, hoping it will work and not bother us. You can probably find a good selection at any of the big home improvement stores, that seems to be the sort of thing they carry a lot of.

Your other request, for year round evergreen shrubs that will thrive in a container, is difficult. It's a little hard to tell from this USDA Plant Hardiness Zone Map for the Northeast U.S., but it looks like Staten Island is in Zone 5a, which means you will have average minimum temperatures of -15 deg to -20 deg. While we may be able to find some evergreen shrubs that could, with careful pruning, remain in a windowbox for some time, remember that when a plant is in the ground, its roots are insulated by the whole Earth. When it is in a windowbox, they are insulated with a few inches of potting soil. In very low temperatures, covering the plant will do the roots no good. If the roots freeze, the plant dies. We found precisely two shrubs that are considered evergreen in New York, Gaultheria procumbens (eastern teaberry) and Ilex opaca (American holly). Neither of these will necessarily stay in bounds or permit pruning that would keep them small. There are a few conifers that stay evergreen there, but they have long, deep roots, and could not survive in a container.

We would refer you again, as we did the last time you wrote, to The Cornell University Department of Horticulture website on Trees and Shrubs for more local information.

Gaultheria procumbens

Gaultheria procumbens

Ilex opaca

Ilex opaca