Well, it didn't work when I first tried to change my profile to accommodate that. But I think it does now.

How does one use the heat zone map without spending the $10 to buy one? On the website you linked they are seeking memberships. Sure it shows the map but it cannot be enlarged to a readable size.

On the other hand we have enough difficulty just getting people to include even their garden zone in their posts and often have to ask for location/or at least zone before we can reply to the question. Often have to ask for it repeatedly.

Then there are those who have no idea what gardening zone they are in much less heat zone.

The current set-up allows room for you to include zone (USDA and/or Sunset), city, state, region, and even heat zone but does no good if folks don't provide the info.

Dave

Fair point. Looks to me like it can be enlarged to a (barely) readable size. That's how I know I'm in zone 10, and I didn't shell out ten bucks, nor am I going to. I can't quite read the "Average" numbers next to the colors on the legend (whatever they are), but who cares. I can read the zone numbers on the color codes there.The point is that Southern Georgia is the same heat zone as me, and Oklahoma is not.

Just pull the graphic off their website and enlarge it.

I agree that people should be more forthcoming about their whereabouts if they want to be helpful, or if they want help. Those people who give me climate-suspicious advice who don't include their location, and especially their zone, I frankly just ignore. But if I see that someone is giving me hot weather advice from the same heat zone as mine, I'll take them more seriously. Their definition of "hot weather" is likely to be similar to mine. Now, there is a Texas Gardening forum here, but there isn't a lot of veggie discussion there.

Here is a link to Texas and adjacent maps.

Here is a link that might be useful: Larger Texas heat zone Map

Cool. It's not just adjacent maps, but there is a tool up at the top to get a heat map for your zip code and adjacent areas. You zoom out from that, and you get it for the whole state.

Looks to me like these heat zones are not quite identical to those in the American Horticultural Society map, but they're pretty close, and the color coding seems to correspond to the AHS map.

Sure would be nice if http://www.plantmaps.com had a heat map for the whole continental U.S. but I'm unable to find one on their website. It must exist.

I think I am z4 on the AHS heat-zone map. Nevertheless we can grow cowpeas and sweet potatoes, and sometimes even lima beans.

That's a nice way of making the point. It's hard for me to grow potatoes here in central Texas, NOT because I'm in the 8b hardiness zone, but because I'm in the 10 heat zone. Potatoes dislike high soil temps (as in 80F and above), and we've got those soil temps in the summer. I've never tried growing them here, but that's what I've heard said.

daninthedirt: Try them in the fall.

Kevin

yes, I think potatoes are a two-season crop in most of TX.

I don't know if AHS gave them permission to post it, but you can find the full resolution AHS heat zone map here ...

http://www.trueblueplants.com/farmer/blueberry-weather.html

Just click on the map to download it. Hot stuff.

The AHS zones are, unfortunately, not terribly useful (although not useless, either). For one, they measure number of days above 86F*, and it really, really matters how long temperatures stay there, as well as the number of days in a row, not just number overall. (Also, is that the high or the overall avg temp for the day?)

Heat in this context is just more difficult to pin down and quantify than cold. Reaching a certain low temperature will definitely kill whatever plant, whereas the inverse with heat is not true.

That's not to say there's nothing useful to be said about veggies and fruits that prefer hotter versus cooler summer temps, the relative uselessness of the original gardening zones when it comes to growing annuals, etc. FAR from it! I'm glad you brought up the topic. This is just about the AHS map in particular.

And finally, even if the map did not have these issues, it's still not used in mainstream venues like on seed packets, etc. As a result the information would have to be gathered and shared at a grassroots level, which HAS happened to a large extent, partly in the region- and state-specific fora and partly in the numerous threads about "heat tolerant ____," "melons for the North," etc.

That's a fair point. But I would say that the plant hardiness zones aren't all that useful either for annuals (which constitute most of vegetable gardening). That's because the average annual extreme minimum temperature (which is what determines those hardiness zones) is usually never reached. That is, the plant hardiness zones tell me what kinds of trees, shrubs, or groundcover I want to put in, with the understanding that those perennials I put in will survive MANY YEARS. If I plant a 5b tree in a 3a zone, it might survive a year, or two, or three, or five, but it'll eventually get killed. I'm in 8b, which means that my temps can get down to 15-20F, but it has been many years since it has ever been that low here.

I would have to say that neither of these zone numbers (plant hardiness and heat) are highly useful, but they do provide some context for the recommendations that are being given in this forum. When I see someone talking about "high temperatures", it really, really depends on whether they are from San Antonio TX or Portland OR, both of which are 8b in hardiness. 100F temperatures are "kinda warm" here in central Texas, while they are "dyin' in the streets" there. I've lived in both places. I know.

So with the understanding that neither or both zone numbers tell the whole story, the two numbers do tell complementary things. I'd venture that for advice about annual vegetables, the heat number may mean more than the hardiness number does.

Thanks for your astute comments!

I totally agree that heat zone is more important in Texas and on the Gulf Coast. "Last frost" is pretty much a joke down here, maybe it will last a few hours at most and then you had better uncover everything before the sun cooks it. To further illustrate the problem, everywhere I look for information on Fall gardening in my area, I see lots of positive information on how wonderful it is to grow in cooler temperatures, but it takes quite a while for everything to really cool down! Will the seeds for some of those wonderful Fall veggies actually germinate here in, say, September, when the soil temp is still pretty hot? I live in Houston. PS my Spring planted garden is just about done and I posted about going on my usual hiatus in July and August. Fellow gardeners in New England thought I was joking...

Squirrel: Germination can be an issue, but not growing, especially if you mulch and/or use some shade in the seedling stage ok planting in the garden.

I start all my fall and winter stuff(except snow peas) inside under shoplights just because of the germination issue.

Just started my brassicas yesterday. They'll go in the ground towards the end of August(our warmest month). I'll start some more in about 3 more weeks along with my lettuces.

Kevin

While the heat zone map may help, it would certainly provide more information, it also unfortunately only helps so much. There are many, many variables and we just have to account for those variables the best that we can. I am in the mountains of NM, zone 6 for the winter. But, my weather is erratic, with frost dates of May 15th and October 15th and virtually no spring. We often have frost May 15th and a week later, the temperatures can go into the 80s to 90s. Not really conducive to peas or potatoes. Another factor for my gardening is sunlight. While many lament not having enough sun, my location at altitude coupled with my proximity to the equator often means too much sunlight for me. So the heat zone map only does so much for those trying to advise me. The best thing is for me to ask my questions, check the answers against the things I have already learned and then experiment to see what suits my location best. Oh, and roll my eyes when someone says something like "since you are in zone 6, you should be able to plant such and such now..."

Yes, tishtoshnm. These numbers certainly aren't a recipe for how to garden successfully. But they do offer a bit of guidance. As I said, I'd find the heat zone number helpful even just in understanding if the person telling me what to do about "heat" is using the word in the same way I am. If you're from Alberta, the word "heat" doesn't mean the same thing to you as it does to me.

As to your "since you are in zone 6, you should ..." I agree completely! I've seen such remarks myself, and they're kind of hilarious.

Good points. I have been saying the same thing for years, that USDA zone numbers mean very little when it comes to vegetables gardening. I have live and gardened in part of GA(7B/8A) and WA(7B/8A) . They are a world apart in terms of growing conditions relating to temperature.

Thanks to Wayne, I just found out that I am in Heat Zone 1(7B WA), as opposed to those who garden in Zone 7B in the south and their Heat Zone is 9 or 10.

About including this info in the profile page so t will pop up in every post/comment:
THAT ZONE BOX IS A DUMMY BOX. IT MEANS THAT YOU CAN ENTER IN THAT TEXT BOX WHATEVER YOU WANT.
Now I am going to edit mine to reflect my heat zone to .
to show "7B WA / HZ 1"
..........................................
I did and it is there.

This post was edited by seysonn on Mon, Jul 8, 13 at 14:48

All good points made here. The conclusion is, as experienced gardeners know but newbies do not, that one must intimately learn the local climate, just as one must become intimately accustomed to the behavior of one's soil at the various times of year.

Things that have a high rate of success here on this island, for example, may not have just a few miles away on the mainland with it's more continental climate. While the mainland has hotter summer days and nights, it has much earlier frost as well.

The factors are too many for attempts to generalize by coding to be anything other than a very rough guide.

Pnbrown, that's a very nice summary of this discussion. There's a lot more to gardening strategy than a couple of numbers. I would just add that the usefulness of such zones, in the context of this forum, is just to roughly understand who we're talking with, and whether we're using words like "heat" in the same way. So those zone numbers in the profile are less about gardening and more about the person who is posting.

Seysonn, I like your idea about how to code the zone in the forum profile. I've done the same with mine.

I agree, the utility of the codes are primarily in seeking advice. They might also be useful if one were seeking another place to grow food.