USDA Hardiness Zones Question?

Question

I'm not very knowledgeable about what all kinds of things can be grown in USDA hardiness zones, but I know what they are. I have a few questions. Please only answer if you're VERY knowledgeable about USDA hardiness zones.

I live in a Zone 5 climate about 15 miles north of the Zone 5/Zone 6 border, could I grow Zone 6, and even some Zone 7 plants if I was willing to risk the occasional year they might not produce?

Can you grow tropical plants in a Zone 7 climate? Tropical plants like oranges, bananas, papayas, guavas, mangos, etc?

I know that northern Minnesota is Zone 4, Fairbanks, Alaska is Zone 3, and Barrow, Alaska is Zone 2, what would a Zone 1 place be? What can be grown in Zone 2 and Zone 1 climates with maybe only a dozen or so frost-free days?

What is the highest hardiness zone? Would it be Zone 11 or is there a Zone 12?

What's the coldest growing zone. Is there a Zone 0?

Thanks in advance to whoever can answer my question.

Answer 1

In general you can easily grow plants from one hardiness zone below and above the one you live in. The trick is understanding the microclimate around your home. The south side of your house is generally warmer. Overhanging evergreen trees can protect plants from frost damage. Over the years I have come to understand there are many climate factors besides cold hardiness that affect growing success.

Most plants are winter hardy in several zones. However, some plants winter hardy in zone 5 may not like the heat of your area in summer. There are now heat zone maps for the U.S. See link below. You can also search "zone 6 plants" and so on for info.

Rainfall can also affect success. Saying a plant has drought hardiness where rainfall is 40" per year may not apply to a dry year in an area with a normal rainfall of 30" per year. Link to annual rainfall rates below.

Tropical plants will die down when the temperature hits freezing. The plants you listed are not likely to produce fruit due to the limited growing season. Zone 9 is the coldest area of commercial production for oranges, which can survive freezing, but will not reliably produce fruit in zone 8. There are some tropical plants that normally go dormant during summer drought that will react to freezing weather as their normal dormancy, and return in spring, like elephant ears. This is limited by how deeply the ground freezes though. For most of the U.S. tropicals must be placed in a heated greenhouse over winter. As to arctic and subarctic plants the first link below provides some good information for a starter.

Answer 2

The lower the zone the colder it is. Plants usually have a zone or two marked on them where they thrive. Certain plants need a specific amount of cold weather-like iris or apricot trees. Any tropical trees like bananas don't tolerate freezing weather but you can put them in a pot and pull them inside for the winter. Super tropical plants will not survive below 45 degrees or will be badly damaged and will have to regrow from the roots. Here we count freezing weather by the minutes and it doesn't take much to damage citrus trees. I used to grow bougainvillas in St. Louis and they were just great in the summer and so unusual for that area. But they had to come inside with lots of light to survive the cold. Go online and research what you want to grow and then you will know if it is worth your time to purchase the plant or tree and what you need to do to make it survive and if you can provide an artificial environment and get the results you want. All the questions you asked can be looked up on line.

Answer 3

I think (and I don't know about hardiness zones etc for sure) that as figs are deciduous, they should be fine over winter. Some plants (less than 300 hours for figs) actually fruit better if they are properly chilled over winter. Problems normally arise if frosts happen during flowering, but due to thee nature of figs, I don't know if even that would be a problem. "When dormant, established trees will tolerate -12C."

Answer 4

http://search.yahoo.com/search?p=usda+hardiness+zones&fr=ush-ans