Question: How does one keep a home at 54ºF during any time of the 24 hour period?

That speaks to me of a very uncomfortable house temperature and if the home is allowed to g0 much below that without the benefit of a furnace, the house will experience all kinds of problems.

We appreciate temperatures like that now and then when sunny skies accompany them but saying you keep a house at those levels just makes me shudder.....and I live in that cold cold east.

Nighttime temperatures are appreciated by plants --in general, and they wont turn up their nose at such levels you speak of....55 - 60 - 65....but they appreicate more what temperatures they would naturally receive in their homeland...and since most houseplants are tropical in nature, such temperatures that normally are there is what they prefer.
You can take the girl out of the country, but you cant take the country out of the girl.
In other words, you can remove a plant from the tropics but you cant take the tropics out of the plant.

I suggest...as I am not familiar with many of the west coast flora and fauna, that you visit a book store---a used book store is my recomendation--and there familiarize yourself with many of the books on houseplants that are usually in great abundance on their tables and shelves.

The books will inform you about the many facets of houseplant care and have pictures to assist your selections.

Plastic or silk would do best in the conditions you are providing.
I just can't see anything surviving with no care and I can't recommend anything.

Lol - I didn't have the guts to offer the same suggestion. The parameters set are extremely narrow; and when coupled with the info that cacti are out and watering/fertilizing will pretty much be ignored, it sort of limits the options.

Al

I agree with the previous three posters that Plasticum artificialis is probably the best choice unless you're willing to commit to raising the temperatures, checking the plant for water regularly, or feed. However, I also think it's probably not a complete lost cause, particularly if 54ish is as cold as the house gets. 54 really isn't that bad, and not all houseplants are necessarily tropical.

Yucca elephantipes could maybe work if you have a very sunny window and don't expect it to do much; I've kept them for a very long time in a very broad range of conditions, including temperatures colder than you describe, and they managed. Not sure if that would work for a whole year, though: I only asked mine to do it for a season. The light thing is non-negotiable, in any case, and I'm unable to promise that they're non-toxic, though I think they are.

Clivia miniata prefers cooler indoor temperatures (maybe not quite that cool, but 54F shouldn't be a problem if that's the coldest it gets), and has a dormancy during the winter where it needs very little water. This is another case where I couldn't promise that they're non-toxic. You would have to remember to water during the summer, though, pretty consistently.

Tolmeia menziesii (piggyback plant) is actually native to the Pacific Northwest, and would do fine with the temperatures, though I don't think they're very tolerant of drying out, so you'd have to stay on top of the watering. Saxifraga stolonifera (strawberry begonia) could probably be made to work also, but again, they will die back a little if they get too dry. Strawberry begonias are also pretty definitely not toxic. Not sure about piggybacks.

I think you can do just about anything to an Asparagus fern and it'll be okay, though they need bright light, they're messy, and the berries, at least (not sure about the foliage), are toxic.

Cryptanthus spp. (earth stars) aren't toxic and will accept lower temperatures, though they also don't handle prolonged droughts well.

Pelargonium x hortorum (geranium) might work okay in a bright spot, though without fertilizer I wouldn't expect flowers, and irregular watering is at least not a good idea, even if it wouldn't necessarily kill the plant.

So I'll dissent from the group insofar as I don't think you're utterly without options, but if you have reason to think you're not going to be able to keep up with watering, or if you don't have good natural light in your home, you're better off with artificial.

i know you said no cactus, but being in the Bay area is excellent for succulents and cacti. I would go with Epiphyllums, a jungle cactus with amazing blooms and most of them have no or few spines. They would grow wonderfully in the Bay area. They can also be hung to keep them away from the younguns. I would suggest going to Reagan's Nursery in Freemont and talk to Don Cravalho. He is a really friendly guy and knows a lot about plants. He should be able to help you or even suggest a good alternative. He also sells larger plants in Castroville at Succulent Gardens.

I do like succulents - just not prickly spines. Thanks for the specific nursery suggestion, too, mentha.
gobluedjm and tapla - I didn't mean to imply that I intend to neglect these plants completely - I do intend to water regularly, just can't have something that needs very frequent watering and misting all the time to be happy. I have an older dracaena that has somehow survived neglect, with occasional water thrown at it all these years (about 15 now!) - it doesn't thrive, but does survive. Plastic is pointless, since the idea is to have some green LIFE here, not just decor.
mr_subjunctive - thanks for taking this seriously and giving me suggestions.
I know that many houseplant are tropical, but there are obviously some that are not. 54 at night is indeed very tolerable since we all sleep under warm down comforters. Why heat the house then? - it gets too hot under the comforter, and it's a waste of precious energy. There are certainly plants in nature that survive even colder nights, so I just wonder which ones like being indoors, and don't mind it a bit warmer during the day. Thanks for all you input.

I have done well with all of the following in cool temperatures. A bonus is that they don't require, or even want, a lot of water when kept so cool. Try philodendron selloum, rubber tree (Ficus elastica), white bird of paradise, and Algerian ivy (Hedera canariensis).

If you can manage it, get some Osmocote fertilizer and apply once a year in April per the directions. It's a timed release fertilizer, good for people who are busy and/or forgetful like me!