The winner: Viburnum, 93/100. Tied for second at 88: Daylily, Catmint.
Zone 3 winters kill politely labeled plants every year. Annuals are excluded on principle here: an annual dies everywhere by January. What remains is ranked on proven cold depth, bloom packed into a short season, and toughness on rough northern ground.
The picks
The flowers that won
The top score, plus the qualifier that asks least of you.
4 rules, 100 points, no opinions. Every line reads one field of the table.
Deep-cold reach40 pointsproven to zone 2 40; zone 3 34; zone 4 26 Read from: the zones it survives.
Bloom packed into a short season25 pointseight or more months 25; six to seven 22; four to five 19; three 12; two 6; one 3; no bloom data 6 Read from: the months it is in bloom.
Care while it grows20 pointslow upkeep 20; middling 11; demanding 3; sources disagree, we average the range; no rating 9 Read from: how much upkeep extension guides report.
Takes rough northern ground15 pointsshrugs off both drought and poor soil 15; drought only 11; poor soil only 7; neither documented 3; no data 6 Read from: stress tolerances.
Not ranked here: an annual cannot be cold-hardy: it dies everywhere by winter; not rated hardy to zone 4.
The full method ↗
The leaderboard
The top ten
The 10 highest of 34 that qualified. Tap any score to open the lines behind it.
Not qualifying is a verdict too: the table simply says this question is not theirs.
an annual cannot be cold-hardy: it dies everywhere by winterSunflower, Marigolds, Zinnias and 12 more
not rated hardy to zone 4 (zones 7 to 10)Anemone, Alstroemeria, Amaryllis and 1 more
not rated hardy to zone 4 (zones 5 to 8)Aster, Blue Flax, Forsythia and 1 more
not rated hardy to zone 4 (zones 9 to 11)Begonia, Cyclamen, Hibiscus and 1 more
The winner's badge
Generated by the ranking above, and re-scored whenever the table changes.
Viburnum
The badge is generated by this ranking, not awarded by hand. When the
table changes, it re-scores itself.
How we rank
We keep one table of 85 flowers,
with 25 documented facts each, drawn from university and extension sources. Every ranking is
a published formula worth 100 points; tap any score and it unfolds into the lines that made
it. A flower that does not fit the question is not scored lower: it is excluded, and the reason is
shown. When the table changes, every score and stamp updates itself.
The full method ↗
