If you are looking at a hardiness zone map, that has little, if
anything, to do with when to plant tomatoes. The general advise it
to plant them out after the night time lows will not go below 50. I
am forced to ignore that rule because, here, the average low for the
warmest part of July is 52. Obviously there will be days that are
cooler than normal and we rarely go a week or 2 without having a
night in the 40s. I just plant my tomatoes in early June and hope
for the best. On a good year, I get ripe tomatoes by mid August. On
a bad year it might be into September.

Steve in the Adirondacks of northern NY



Al Dykes wrote:

I live in an area where three zones meet on the zone map.
It seems to me that instead of guessing my effective zone, planting
tomatoes comes down to soil temperature and the expected minimum
nighttime temperature.

Does anyone plant this way ?