AZ is hotter than FL but its a dry heat thus so many less insects and fungal issues. Same for many parts of CA. Grapes grow awesome in Phx. We grew lots of yummy seedless grapes there. I really wish I could grow those types there. There is a bunch of blackish purple grapes growing wild all over our property. They have seeds and don't taste all that great. I let the chickens eat them. Maybe they are better for making jams? Anyone know of any seedless varieties that will grow in zn 9a (NE FL)?

I find it strange that so many people are trying to grow northern vegetables following a northern calendar in FL. No wonder you're having so much trouble! I'm in central FL 9B and I grow stuff all year round - but what I grow changes with the temperatures. For example, this past year in the cooler months (late fall/winter) I grew lots of leafy greens like lettuce, chard, cilantro, garden and red sorrel, bok choy, radishes, carrots, and peas. I've got a few pigeon pea "trees" (they live for ~5 years and produce pigeon peas year round. They are drought tolerant and infertile sand tolerant). I've got straight Myakka sand and I haven't been amending. To my surprise, quite a few plants were very happy in my infertile sand. The only thing I do is occasionally add some coffee grounds once in a while or some diluted urine. I'm now in the process of making and charging biochar to long term improve the fertility of my sand since any compost I added in the past disappeared almost immediately (to be honest, it disappears in my compost bin before I even really get a chance to use it). In October I started tomato plants from seeds - now that it's March they are flowering and fruiting. Everglades tomato is a FL native tomato that can perform even during our crazy hot and humid summers. There's also Floradade tomato, which was developed in south FL specifically to cope with the brutal summers and can handle up to 100F. I've got those sprouting now (mid March) so we'll see how they do. There are at least 10 other tomatoes I know of that purportedly thrive even in FL summers but they will not be the tomatoes everyone knows in the north. If you want to grow northern tomatoes, just do it in the spring; most tomatoes will drop flowers by June due to the heat. If you can keep the plant alive through the summer (usually by shading it from afternoon sun) they will start producing again in the fall when temps cool down. I've also got sweet and hot peppers, sweet potatoes, cowpeas, eggplant, callaloo (amaranth), garlic chives, lagos spinach, New Zealand spinach, Ethiopian Kale, Malabar spinach, Roselle, Cranberry Hibiscus, Chaya, and Moringa for the summer. Rule of thumb for FL gardening: Southeast Asian + Caribbean veggies do particularly well in FL summers and "northern" veggies grow well here in the winter. As for fruit trees... stop trying to grow what does well in the north and grow what does well here. I've got a monster guava that I never fertilize or water and can deal with the occasional cold snap. Mulberries also do particularly well - they are basically zero maintenance (no extra watering, fertilizer, thrive on neglect). They fruit multiple times a year (mine are flowering now). There are plenty of other options if you look.

bsewall- Great comparison! yes...these two areas are wildly different when it come to freezes. The Tampa data comes from the airport, which is located north of Tampa Bay. So, when the cold fronts roll down from the north, the bay cant help anywhere near as much as it does for the St. Pete station, which as I mentioned above, is located literally in Tampa Bay on the south east part of Pinellas. Here are a few more plots to further illustrate your point. They come from the Southeast Climate center as show the probability of going 365 days in a row without the temperature dropping below a certain value. As can be seen in these charts, there is an 80% chance of going 365 without the temp dropping below 36F at the St. Pete station, but only a 30% chance of that happening at the Tampa AP. What I really like about these charts is that they are based on really long term data (since 1900 for Tampa and 1948 for St. Pete).

There isn't one. I've wasted countless hours analyzing all of the available maps and, until the revised USDA Hardiness Zone Map is released next year (hopefully), there is no reliable map available. I have a whole section on my web site devoted to Hardiness Zone Maps (http://www.centralfloridagarden.com/topics/hardiness/overview.html), but for a quick idea of how all this impacts Florida, try the link below. My guess - you are on the northern edge of Zone 10. The current USDA Hardiness Zone Map (it's 18 years old and desperately in need of an update) would have you on the southern edge of 9B, but all of the interim maps issued since 1990 show you in Zone 10. My other guess is that the next update of the USDA Hardiness Zone Map will be similar to the AHS and other interim maps and it will confirm you are in Zone 10. Since I'm on a run with guessing - I'd also guess that you have the same problem I do. I live in Lithia, also on the edge between 9 & 10, which means I get lulled into thinking I live in the tropical paradise of Zone 10 until a killer frost barrels in from the North every two or three years. It's enough to make a person schizophrenic. Here is a link that might be useful: Florida Hardiness Zone maps