Who should I listen to?

My ag extension has a very handy calendar showing when to plant what, along with spacing, dates to harvest, and whether to start from seed, transplant, etc.  

My problem is, this calendar varies greatly, in some cases, from what Mel's book says, in regards to when to plant.  For example, our last frost averages April 12.  For broccoli, Mel lists earliest outdoor planting as 5 weeks before last frost, which would make it Mar 8.  Ag extension says I can put transplants in Feb 15.  Mel puts cabbage at the same 5 weeks before frost, and the ag calendar says I can put in in Feb 1!  Carrots are even more extreme.  Mel says my carrots should go in no earlier than Mar 22. and the ag calendar says Feb 1.  We're talking about a 7 week difference here.

So, what to do?  Our hot weather (central NC) can arrive really early, and so I want to get these cool weather crops in ASAP to have a hope of getting any harvest before they're gone with the heat.

I'm tending to favor the calendar... being produced by a local extension, and specifically for this region, I would think they would know best.

Any advice?  Thanks in advance! 

I'd go with the calendar from the local ag extension if it were me. Take notes. Good luck!

Do you have an older gardening neighbor to ask about your dates. I find their advice to be helpful or at least colorful. Has your area shifted its zone designation? I know our area got a zone warmer, so now my old gardener dates line up with the extension office dates pretty closely? They did not before. Or carrot seeds are cheap, you can always go with the earliest dates and replant if a disaster strikes. How is that for wishy washy help.

Patty from Yorktown

I would go with your extension, because you can always plant more seeds.  I think the book planting dates are helpful but also more of a guideline to get you started then as you get more experience of what works best for you then you just go from there!  Happy planting!  I am jealous, I'm months away!

I suggest following your local agriculture extension service recommendations. They are a most valuable horticulture/agriculture asset in your area.

I'm on the Texas Gulf Coast, so like you, our warm weather comes early.  I follow the plant dates set out by TAMU for our Zone 9 (Texas A&M University Agricultural Extension).  Burpee's has my zip code listed as Zone 8, which couldn't be further from the fact.  I ordered my seed potatoes from them, but had to cancel my order because they don't even start shipping until Feb. 28th.  TAMU advises planting them Feb. 1 - 14th for my area.  My Dad always planted his around Valentine's Day.  So I bought my seed potatoes at a local feed store that already had them in.  I e-mailed Burpee's and told them their Zone number was off for my zip code and they couldn't care less.  They said they weren't shipping any seed potatoes before Feb. 28th, including mine.  Two other gardeners I know in my zone have also canceled their potato orders with Burpee's for the same reason.  We heat up early and fast down here on the Gulf Coast.

I would like to amend my previous statement to say take the planting dates from your extension service, but the spacing is intensive in the SFG so follow Mel's recommendations on most spacing of plants.

Additionally, you can check seed sowing and transplanting dates on Johnny's site or the Old Farmer's Almanac gardening calculator.

Thanks, everyone.  Seems like the consensus is to go with the calendar, as I had suspected.  I don't really know anyone to ask... I'm new to this myself, and not too many in my neighborhood do vegetable gardening.  Last year I had no idea what I was doing and we still did pretty well for a first-timer.  But this time I'm armed with information, and a plan, and I'm really excited to see what we can produce.  SFG is such a fun and rewarding experience for my girls!

Johnny's is somewhere between Mel's and the calendar's recommendations.  It does appear that our zone was 7a a few years ago, and is now 7b according to USDA.  And though the 50% last frost date is Apr 12, last year's last frost wasn't until Apr 29 (which boggles my mind, because knowing our climate, it was probably 90 degrees on May 15).  So I think I'm going to be just a bit conservative, but use the calendar.  (The calendar has a range of dates for everything anyhow... carrots are listed as Feb 1, 15, Mar 1, 15.)

Thanks for all the advice!

Your Extension Service is an incredible source of information. They may even be offering some workshops on gardening.
http://www.ces.ncsu.edu/