I need help determining my planting "Zone". I live in Slidell, LA, and maps/resources across the internet have stated that I'm in Zones 8-9a... However, I'm wondering which one it really is. Is it Zone 8a, 8b, or 9a? Thanks. :)
I'm in Pearl River, LA. USDA says I'm in 8b, which is what I've been going by. But if I lived one zip code south, I'd be 9a. Interesting. Sorry, I know that doesn't help.
A definite 8b. See link below. This is a great interactive map with tons of good information.
Carol in Jacksonville
Here is a link that might be useful: Interactive USDA Gardening and Plant Hardiness Zone Map for Louisiana
Hi & welcome to Gardenweb!
You're very near a state border as I am, 15 MI from FL. It's frustrating that these maps cut off the zones at the borders. It would be helpful to see how the zones flow across these arbitrary lines, how far away the change occurs without having to look up the other state and mentally combining the images.
Not every ZIP code has an official reporting station, so they're somewhat based on nearby averages that can be slightly different. They also still fail to show small pockets of well-established, reliable microclimates, such as parts of NOLA where there are things going on that definitely wouldn't happen in real 8b.
But, really, the difference between 8b and 9a is as thin as gauze, and not all winters are the same. With excellent drainage, microclimate and zone-cheating techniques, you should "get away with" most Z9 plants, but personally I wouldn't devote much $ to them. The close proximity of large bodies of water should have an even more moderating effect for you than what I can achieve here.
When one may be shopping often in a different zone, you sometimes have to do a bit more homework on the perennials.
The biggest effect of making my zone 9a yard a "tropical" has been numerous plantings of trees. I have several live oaks, magnolias, red maples and tons of crape myrtles. The tree canopy offers TREMENDOUS - it cannot be overstated - INCREDIBLE protection in winter. I left all kinds of non-cold hardy plants out all winter long under these big trees: begonias, bromeliads, anthuriums, hoyas, succulents and others. They all survived without so much as a scratch. These would have never made it without the wonderful protection of the canopies. In my book, large evergreen trees are the number one way to change your zone into a microclimate for the next zone higher.
BigGreen, I am also in a transition area. So I chose to not go by the published USDA zone maps. Instead, I have used my observed typical average low temperature for the entire year as a means to determine my zone. Zone 9a has an average lowest temperature of the year equal to 20 to 25 deg F; zone 8b is 15 to 20 deg F. Knowing that my typical lowest temperature for the whole year is in the 20 to 25 degree range, I put have always considered myself to be in zone 9a. (Although, for the last 2 or 3 years my lowest temperature has been in the 25 to 30 degree F range, zone 9b)
Coincidentally, about a year ago the zone maps were revised. Before the revision, in my opinion I was incorrectly shown as 8b. The recently revised new maps show me as 9a... which is correct.
You may want to also check out the Sunset Zone Maps, these are probably more helpful when it comes to planting.
Here is a link that might be useful: Sunset Climate Zones
This post was edited by grandad on Thu, May 2, 13 at 15:05
I also live in Slidell and per the new USDA map my 70461 zip code is 9a. I can also tell you from living here my whole life that we are definitely 9a. Actually I'm not sure when the last time was we dropped below 25 so that would make it 9b at least in my neighborhood with tons of pines and live oaks.
Oh and that map linked above is old. There is no way in hell New Orleans is 8b! In reality its more like a 10.
You're right - my mistake. That was the 1990 map. Here is a link to the 2012 map.
Here is a link that might be useful: 2012 USDA Plant Hardiness Zone Map