I am currently harvesting Russet potatoes that I planted in Central Florida around late December. I also have Russet potatoes I planted about 2 months later that are flowering right now. In between these plantings I planted Red Pontiac, Purple Majesty and Yukon Gold potatoes. The varieties have varying maturity times (early, main crop, Late) is the seasonal descriptions I have seen used which corresponds to about 85, 100, and 130 days to harvest. If you plant in late winter/early spring at about the last freeze date, or slightly before, you want the harvest date to be before temperatures get too hot. Or if you plant in late summer to early fall you want to harvest before the first hard freeze. Here are the maturity times on my plantings:
Early:
Yukon Gold
Main:
Red Pontiac and
Purple Majesty
Late:
Russet
In Florida I can get two plantings. In Colorado (high in the Rockies) I could only get one planting.
I think heat would be the enemy around here. We’ll get 100-degree highs any time from April into October, but June and July can easily top 110 on any given afternoon and it hits 117 or 118 some days.
The worst freezes are usually in January, maybe two or three consecutive nights into the low twenties. Last touch of frost sometime in late March or early April, generally just after I plant peppers.