I agree that it's a huge problem: how to list very important data that varies a lot from region to region.
"Ultra early" might mean 50 days in a warm climate, but 70 days in a cool climate.
I think that "frost-free growing season" means little to tomatoes.
Is there any name for the period between
"when nights stay above 50 degrees and days below 95"?
Or those numbers might have to be 55 and 90, or 100 ...
I doubt if it helps much to say that Territorial Seeds lists
Ultra Early varieties from 55-65 days.
Extra-early 68-80 days.
Early 75-80 days.
They're in Cottage Grove OR (97424?)
50% frost date April 22?
USDA Hardiness Zone 8b: same as parts of Texas and the PNW, wildly different climates.
I picked the vaguest possible terms because they hopefully have some meaning as relative terms.
"Ultra early" should be earlier than "very early" almost everywhere (unless some variety is especially sensitive to something like "how fast spring warms up".
Then people in evey region would need to learn how "ultra" or "very" acts in their region, their micro-climate, their soil, and their style of gardening.
Perhaps a solution would be Dave's "mouse over pop-up". If that can be a multi-line box, it could define each vague term with something like:
Very-Early:
50-65 days in Texas Zone 8
60-70 days in NY Zone 6
70-80 days in Western WA Zone 8
Add 5 days if not South-facing or South-east-facing
Add 10 days for partial shade.
Add 10 days for heavy wet clay.
Probably not practical!
I think that listing the actual number of days to maturity claims more detail than can really be true: it depends on the year and your micro-climate and probably many other things. Asking experienced neighbors may be the best way.
If I knew a LOT more, I would try even to just LIST the relevant factors, and maybe pick a few representative regions and micro-climates and methods:
- transplanting outdoors ASAP under plastic or with wall-o-water
- transplanting outdoors ASAP "naked"
- transplanting outdoors conservatively late without protection
- direct sowing under plastic, clocjes or with wall-o-water
- direct sowing naked.
Some people have said that the fancy early-start tricks don't really get them tomatoes earlier, that the earlier you start them, the longer the time to ripeness. I don't know, but it is fascinating!
My suspicion is that days-to-ripeness may depend most heavily on something like degree-days: for each day the averge daily temperature (or max temperature?) is above 68 degrees, add the number of degrees above 68 to a total.
If true, that makes me sad, because it would be easier for me to "beat the frost" or even to "keep nightime lows above 50" than it will be to create "warmth" all spring and early summer.
Hence my interest in ultra-early and cold-tolerant varieties. I don't really know yet which I need more (coastal PNW, USDA Zone 8b, Sunset Zone 5, long cold wet spring, short cool dry summer).