Janet, I've got a young (3-yr) yard with several natives. Let me know if you are interested in visiting the yard (Yorba Linda/NOC area) so you can help yourself to cuttings and/or some seeds.

I'm not that familiar with California native plants, but one thing to consider is the fire hazard in California, depending on which area of the state your boyfriend's mother lives. I've never grown bamboo, and am not sure what kind of fire-resistance it has, or how much water it needs. I have seen people growing bamboo on the East Coast in swampy areas. Below is a link to some info from the L.A. County Fire Department on this topic. They list some fire resistant and drought tolerant plants, along with info about fire-resistant landscaping, erosion, etc. Some of the plants on the lists are native, but some are non-native. I believe this is due to the fire-resistance of some non-natives that makes them desirable in California. If your boyfriend's mother lives in an area with a high fire risk, you can try checking with the Fire Department for your boyfriend's mom's county or city/town in California to see if they have a list of recommended fire-resistant plants, shrubs and trees, and what they say about bamboo. You can also contact the California Native Plant Society for more info: California Native Plant Society: http://www.cnps.org/ Here is a link that might be useful: LA County Fire Department-Vegetation Management

I am also in zone 6b and speak from 50+ years of experience in wanting tropical looking plants and succeeding with many. But of course there have been many failures. No palm trees will grow reliably without some protection, or possibly a very protected microclimate. The only ones that MIGHT survive are needle palms (Rhapidophyllum hystrix) or maybe windmill palm (Trachycarpus) with protection. You definitely CAN grow several types of cacti and succulents in your zone. Many opuntias and others are fine, but the key to success in our cold and wet winters is to plant on slightly higher ground so that no water sits around the plant. I have slightly mounded the area, and then mulched with small stones (1 inch size) about three inches deep. Not only does this make the area appear lever (remember the soil under the stones is mounded a little) but it reflects warmth and keeps the plants high and dry. I've grown them for years and get hundreds of blossoms and fruit. Many camellias are perfectly hardy in zone 6b. Also, aucuba japonica, which is a nice shrub with large leaves spotted with cream or gold on green. It keeps it's leaves all winter. Google and you'll find lots of varieties. Also, some large leaved evergreen magnolias will grow well. I have a large "Bracken's Brown Beauty" that has large white flowers, and shiny evergreen leaves with a rusty brown fuzz on the reverse. Gorgeous! You might also want a nice flowering vine that keeps its leaves all winter. Gelsemium sempervirens "Margarita" is a beautiful and strong grower covered with beautiful yellow trumpet flowers in spring. Strong grower but easy to trim if needed. I also have a winter jasmine (Jasminum nudiflorum) and although not necessarily 'tropical' looking, it does have stems that are green all winter, and blooms during any warm spell in winter or spring. In fact I have a few blossoms open now. They're yellow, not unlike forsythia. When I get a chance I will try to post some photos. Good luck with your new garden. You have all winter to research and plan so you'll be ready when spring arrives!

North American species of milkweed need to have their seed cold stratified during the winter months in order to assure optimum germination, as mentioned by napapen. Most methods use a cold, moist stratification. I've not had personal good luck using a moist medium, but rather a dry medium. I seem to grow molds better the moist way than germinate milkweed seed (or any other seed needing cold strat for that matter). Check out the two links below that will help teach you the technique(s): How To Cold Stratify Seeds: Cold Moist Stratification of Milkweed Seeds Start them now, as the winter season is in full gear. I stratify mine for 6-8 weeks before planting. That will put you roughly in March for potting up or placing them in the ground. A. fascicularis is especially easy to germinate. With A. fascicularis, you should be able to harvest seed the first year if your plants are growing strong and vigorous. A. speciosa may take two or three years before they set seed. Keep us posted on your endeavors!