Zone 6 Perennials

Zone 6a and zone 6b

Both halves grow the same plants — hardiness ranges in our library are whole numbers — but they are not the same winter. Zone 6a bottoms out around -10 to -5°F and 6b around -5 to 0°F. The colder half freezes earlier in autumn and thaws later in spring, so the same plant goes in the ground a week or two later there.

What actually kills perennials in zone 6

Not the cold. Only 77 of these 695 treat zone 6 as their cold limit; 469 survive two zones colder. What takes them out is winter wet and frost heave — roots sitting in ground that freezes wet, and shallow-rooted plants pushed up out of the soil by the ground thawing and refreezing through February. Both are drainage problems wearing a temperature costume. A raised bed and a mulch laid after the ground freezes, not before, do more for survival here than moving up a hardiness zone.

A perennial-only border has no back row

Of these 695 perennials, only 26 are tall enough to sit at the back of a bed — against 1,017 plants across the whole zone 6 library once shrubs, grasses and small trees are counted. This is not a gap in the list; it is what perennials are. A border built from this page alone will be two-thirds of a border.

Put these in your own yard

Upload a photo of the space and get a design back using plants that survive your winter.

Where these numbers come from

Zone boundaries come from PRISM Climate Group's 2023 plant-hardiness dataset at Oregon State University, covering 40,502 US ZIP codes. Hardiness range, light requirement and mature size are checked against the Missouri Botanical Garden Plant Finder and the NC State Extension Gardener Plant Toolbox.

Price is an estimate sampled from published 2026 nursery price lists by container size, and varies by region, season and supplier. This is not the official USDA map and it cannot account for soil, drainage, wind, local microclimates or planting restrictions. Confirm a final purchase with a local nursery.

One limit worth stating plainly: this list is a subtraction, not a classification. Our plant-type field groups anything that is not a tree, shrub, vine, grass or groundcover as a perennial, so 64 rows have been taken back out — roses and hydrangeas, which the authority files as perennial *and* woody, plus a handful its own life-cycle data calls annual or biennial. Where no field separates a row from a real perennial we have removed it by name, one at a time, which means the ones we have not found yet are still here. If something on this page does not come back for you, that is the likely reason, and we would rather say so than be told.