I'm not sure about southeastern Pennsylvania but there are some newly introduced begonias that are fairly hardy, and some older ones are turning out to be hardier than anybody realized. Among the hardier species are B. emeiensis, B. formosana, and B. pedatifida. 'Torsa', 'Little Brother Montgomery' and 'Connee Boswell' are older hybrids that have turned out to be fairly hardy. Most of these will survive a mild winter in zone 7; a cold winter (and our last several have been quite mild!) is probably another story entirely. The key is to start with healthy, well-grown plants, get them in the ground early in the growing season, plant deeply, and mulch in the fall. As long as the rhizomes don't freeze, many will return. For sources, check out the listings in the Plant Delights Nursery catalog. I would also suggest getting in touch with the Delaware Valley Branch of the American Begonia Society to meet fellow begonia growers and obtain new plants. Here is a link that might be useful: Delaware Valley branch

It may depend on what kind of winter we have. If I were you, however, I'd consider the possibility of leaving them intact over the winter. I'd watch what happens, but wait till spring to cut them back. That way, if you get dieback, you'll at least have something to cut off that you didn't want to keep anyway. That said, because it's an annual (we're talking catharanthus--vinca rosea--not vinca minor, as in periwinkle/creeping myrtle, right?), even if it survives, it may not be as lovely and floriferous as it was this year. Stems get woody, and plants do get tired and bloomed out, especially if they've set seed. Kay

Okay just to make a quick distinction here, because I know that I've read both (Do caulk! ... Don't caulk!) I wanted to mention that the installation best practices make a clear distinction between color plus (ie painted) and primed hardie plank. The color plus CAN NOT BE CAULKED without voiding the warranty. The primed planks may be caulked, but I believe the flashing methodology outlined is still preferred. That reference is here: Plank Best Practices This helps for when I read articles like the next one that only talk about how important it is to caulk and do it properly when installing hardie plank. They are likely only discussing the installation of primed plank, which is what we are leaning towards due to the limited color choice. Always caulk article

Hardiplank siding paints up real nice. Make sure all caulking is complete. Make sure all cut ends are primed where possible. Good installers prime every cut before installing. No need to prime siding as hardiplank comes preprimed. Flat tends to look the best when new but will get dirty quickly. Satin is your best overall choice. Have them put on 2 coats for a paint job that will last a long time. I wouldn't put too much stock in the 'lifetime' claim. That is based on the average homeowner only staying in a particular house for 7 years. I have been using Duration since it came out, no complaints yet.