Perennials by Zone

Updated September 2026 · Garden Advice Guide

Sorting perennials by zone is the first filter, and it works in one direction only: a plant rated to your zone number or a colder one survives your winter, and a plant rated warmer than your zone does not. Zone 5 can plant anything labeled 3, 4, or 5. Zone 8 can plant anything up to 8. The tables below run zones 3 through 10, split by sun and shade, with the bloom window, the mature height, and the spread, which is the number most people ignore and then regret three years later.

Get your number right first: run your ZIP through our free growing zone lookup, because the whole page below is useless if you are guessing, and a lot of people are one zone off from what they assume.

Updated September 2026

What a zone rating actually promises

A USDA hardiness zone is one statistic and nothing more: the average annual coldest night in your area, in 10°F bands. Zone 4 averages -30 to -20°F, zone 5 is -20 to -10°F, zone 6 is -10 to 0°F, zone 7 is 0 to 10°F, zone 8 is 10 to 20°F, zone 9 is 20 to 30°F, and zone 10 is 30 to 40°F. The a and b halves split each band at 5°F.

Here is what that number does not tell you, and each one of these kills more perennials than cold does.

• Winter wet. Lavender, agastache, dianthus, penstemon, and most silver-leaved plants are rated to zone 5 in well-drained soil and rot at zone 5 in heavy clay. If a plant on the list below is described as needing sharp drainage, read that as a hardiness condition, not a preference.
• Summer heat. Zone ratings have no top end in the USDA system, which is why the tables below carry a warm-end number as well. Peony, delphinium, lupine, bleeding heart, and hosta all fail somewhere in zones 8 to 10 from heat and lack of winter chill, no matter how tough they are in the cold.
• Chill requirement. Peonies need roughly 500 hours below 40°F to set buds. Hosta needs about six weeks of cold to break dormancy properly. In zone 10 they simply decline. This is why the zone 10 list looks like a different hobby.
• Snow cover. A dependable foot of snow is better insulation than anything you can buy, so a zone 4 garden that stays buried behaves like zone 5 at the crown. An open, windswept zone 4 garden with no snow behaves like zone 3.
• Your own microclimate. A south-facing bed against a brick wall runs a half zone to a full zone warmer than the low corner at the bottom of your yard. Both are on the same map.

Treat the zone as a hard filter that removes the impossible, then use the rest of the tag to choose among what remains.

Perennials by zone: how to read these tables

Each table gives the plant, its hardiness range, when it blooms, mature height, mature spread, and a note on what it needs. A few conventions that will save you confusion:

• The range is inclusive. "Zones 3 to 8" means it works in 3, 4, 5, 6, 7, and 8, and fails in 9.
• Warmer zones inherit everything above them. The zone 5 and 6 tables list the plants that become available at 5 and 6. Nearly everything in the zone 3 and 4 tables also grows in 5 and 6, so read your section plus every colder section above it.
• Bloom windows shift by roughly two weeks per zone. A plant listed as June in zone 6 opens in late May in zone 7 and mid June in zone 4.
• Spread is the mature footprint, not the size of the pot you buy. This is the number that decides how many plants you need, and it is the one people get wrong.
• Fall bloomers are deliberately thin here. Asters, mums, Japanese anemone, sedum, helenium, toad lily and the rest of the September to November group have their own by-zone tables on our page for fall flowering perennials. This page covers the rest of the year so the two lists do not overlap.

Zones 3 and 4: the cold end

Zone 3 and 4 gardeners have a shorter list than anyone, but the plants on it are the toughest in the trade and they last for decades. A peony planted in zone 3 will outlive the person who planted it. The limiting factor here is not cold so much as season length: with a frost-free window of 100 to 130 days, late summer bloomers can get caught before they open.

Full sun perennials for zones 3 and 4

Shade perennials for zones 3 and 4

Zones 5 and 6: the widest choice in the country

Zones 5 and 6 can grow nearly every plant in the zone 3 and 4 tables plus a large second tier that opens up once the winter low stops going below -20°F. This is the range most American perennial catalogs are written for, which is both an advantage and a trap, because a plant sold as "hardy" without a number usually means hardy in zone 5.

Full sun perennials that become possible in zones 5 and 6

Shade perennials that become possible in zones 5 and 6

Shade perennial selection overlaps heavily with the deer question, since browsing pressure is worst in exactly the wooded edges where shade gardens sit. Our page on deer resistant shade plants sorts the same plant palette by how much deer actually leave alone, which is a different axis from hardiness and not repeated here.

Zone 7: where southern conditions start

Zone 7 is a hinge. It still gets enough winter chill for peonies, lilacs, and bleeding heart, and it is warm enough for the first wave of southern perennials. It is also where summer heat and humidity begin to shorten the life of northern plants: delphinium becomes a two-year plant, lupine becomes an annual, and phlox needs more air movement than it did in zone 5.

Zones 8 and 9: heat is the limiting factor

Above zone 7, the question flips. Nothing you plant is going to freeze; the problem is that summer nights stay in the 70s and 80s for weeks, humidity keeps foliage wet, and there is not enough winter chill for plants that need dormancy. Read the warm-end number in the tables above carefully, because that is the number that governs your garden.

What to stop trying in zones 8 and 9: peony (needs chill hours, only the very earliest cultivars manage in 8a), delphinium, lupine, bleeding heart, Oriental poppy, most bearded iris in 9, and blue-leaved hosta. Substitute Louisiana iris for bearded iris, hardy hibiscus for peony as the big early summer statement, and Farfugium or cast iron plant for hosta.

Zone 10: perennials that never go dormant

Zone 10 is the smallest section here because the whole framework changes. Almost nothing goes dormant, "perennial" means a plant that keeps growing year-round rather than one that dies back and returns, and the pruning calendar replaces the winter protection calendar. The plants below are the reliable backbone.

The plants zone 10 gardeners keep trying and losing are the chill-dependent classics: peony, lilac, hosta, bleeding heart, delphinium, tulips, and most bearded iris. None of them are failing from heat alone. They are failing because they never receive the run of nights below 40°F that tells them a year has passed.

Ornamental grasses by zone

Grasses do a job no flowering perennial does: they hold structure from July straight through winter, they move in wind, and they need almost no maintenance beyond one cut a year. Every mixed border benefits from having roughly a quarter to a third of its area in grasses.

Two structural rules for grasses. First, most of them want lean soil and full sun, and the single most common failure is a big grass planted in rich, irrigated soil, where it grows soft and splits open in the middle by August. Second, they get cut once a year, and the timing matters for both wildlife and appearance; our page on when to cut back ornamental grasses covers the late winter window and the two exceptions to it.

Ferns and the shade floor

Ferns are the most underused perennials in American gardens, and they solve the hardest problem in landscaping: a dry, rooty, shaded area under mature trees.

Practical planting note for dry shade: dig the hole, fill it with water, let it drain, plant, then mulch with 2 inches of shredded leaves. Water weekly for the entire first season without exception. Ferns that are established are drought tolerant; ferns in their first summer are not, and that single year of attention is the difference between a fern colony and a row of dead crowns.

Creeping thyme and the walkable perennials

Creeping thyme gets asked about more than any other ground cover, usually as a lawn replacement, and the honest answer is that it is excellent in a narrow set of conditions and a failure outside them.

The conditions creeping thyme requires are strict: full sun for at least six hours, drainage sharp enough that water never stands, and soil that is not rich. It fails in clay, it fails in shade, it fails where snow sits wet on it all winter, and it does not tolerate the traffic of an actual lawn. Use it between pavers, on a hot slope, along a path edge, or in a hell strip. Do not use it as a substitute for turf in a yard where children play.

Calla, canna, and lupine: the three that need their own answer

These three come up constantly on by-zone lists, and each one behaves differently from the tables above.

Calla lily

Two different plants share the name. The white Zantedeschia aethiopica is hardy to zone 8, evergreen in zones 9 and 10, grows 24 to 36 inches, blooms in spring and early summer, and will grow in permanently wet soil at a pond edge. The colored hybrids from Z. rehmannii and Z. elliottiana are hardy only to zone 9, stay 12 to 24 inches, and need a genuinely dry rest period after bloom or the rhizome rots.

In zone 7 and colder, treat callas the way you treat dahlias, a job our guide to preparing dahlias for winter sets out step by step. After the first frost blackens the foliage, cut it back, lift the rhizomes, cure them for a week or two somewhere dry and airy, and store them in barely damp peat or shavings at 50 to 60°F. Growing them in a pot you can move whole is simpler than digging every fall, and it also lets you enforce the dry dormancy the colored hybrids need.

Canna

Cannas are hardy in the ground in zones 7 through 10, and in a sheltered zone 7 bed with a heavy mulch they come back reliably. They grow 36 to 96 inches depending on cultivar, bloom from midsummer until frost, want full sun and as much water as you can give them, and are one of the few perennials that will grow in a boggy spot in full sun.

In zone 6 and colder, lift them. Wait until the first frost blackens the leaves, cut the stalks to 4 to 6 inches, lift the whole clump with soil clinging to it, let it dry for a few days, and store it at 45 to 55°F in barely damp material. Do not wash the rhizomes; the clinging soil is what keeps them from drying out. Divide in spring, not fall.

Lupine

Lupine is the plant most often bought from the wrong list. Russell hybrid lupines are hardy in zones 4 through 8 on paper, but the real limit is summer, not winter. They need cool nights, and in zone 7 and warmer they behave as short-lived annuals no matter how well you site them. Even in zone 5 they are naturally short-lived, giving two or three good years before they decline.

What they need: acidic soil, sharp drainage, full sun to light afternoon shade, and no disturbance, because they form a deep taproot and resent transplanting. Buy small plants or sow seed in place in fall, nick or soak the seed first, and let them self-sow. Wild lupine (Lupinus perennis) is the tougher, smaller native option for zones 3 to 8, and Texas bluebonnet is an annual and will not come back from the crown at all.

Height, spread, and how many plants to buy

The spread column is the one to plan from, and it is the one nursery tags bury.

The working method: take the mature spread of the plant, and space plants at roughly that distance center to center for a solid mass, or at 1.5 times that distance if you want each plant to keep its own shape. A hosta with a 30 inch spread planted at 30 inch centers closes into a continuous carpet in about three years. The same hosta at 18 inch centers looks great in year one and becomes a crowded, mildew-prone mess by year four.

To fill a bed, multiply the area by a plants-per-square-foot figure taken from the spread:

Two adjustments to that math. Plant in odd-numbered drifts of three, five, or seven of the same thing rather than singles, because a single specimen of twelve different plants reads as clutter and a drift of five reads as design. And leave the front 12 inches of the bed for something under 12 inches tall, because a bed with no low edge looks unfinished no matter how good the middle is.

Building a border that is never empty

Zone tells you what survives. Bloom window tells you when it performs. A border stocked entirely from one column of the tables above will have three spectacular weeks and five dead months.

Using a zone 5 or 6 garden as the example, here is a sequence that never has a gap between March and August:

• March: hellebore, lungwort. Both in shade, both flowering while there is still snow in the shade.
• April: brunnera, bleeding heart, epimedium, tiarella, amsonia.
• May: peony, bearded iris, Siberian iris, catmint, salvia, baptisia, dianthus, Oriental poppy.
• June: daylily, shasta daisy, lavender, penstemon, coreopsis, veronica, astilbe, sea holly, hardy geranium.
• July: phlox, liatris, bee balm, coneflower, crocosmia, kniphofia, hardy hibiscus, balloon flower.
• August: phlox continuing, coneflower, gaura, catmint's second flush, and the grasses coming into plume.

From September onward the fall bloomers take over, and rather than repeat their tables here, the by-zone lists for that stretch are on our fall flowering perennials page. Slot one or two of those into every section of the border now, while you are planning, because the September gap is the one everybody discovers too late.

Perennials are only one layer. The woody plants that frame them have their own hardiness rules, and those are on our shrubs by zone page for the flowering and evergreen backbone, our fast growing shade trees page for the canopy above the border, and our fruit tree growing zone guide page if any of that canopy should also be edible. Pick the woody layer first, because it sets the sun and shade the perennials then have to live with.

Two more scheduling rules worth building in. Plant something with three-season foliage next to every spring bloomer that goes dormant, because Oriental poppy and bleeding heart both leave a bare hole in July. And in any garden with browsing pressure, run your final list past our deer resistant perennials page before you buy, since a beautifully sequenced border is worth nothing if half of it is eaten in June.

Frequently asked questions

How do I know which perennials will survive my winter?

Find your USDA hardiness zone number, then buy only plants whose rating includes that number or a colder one. A plant rated zones 4 to 8 is safe in zones 4, 5, 6, 7, and 8. Watch the warm end of that range too, because in zones 8 through 10 a plant more often fails from summer heat and a lack of winter chill than from cold.

What are the longest blooming perennials?

Geranium 'Rozanne' from June to October, catmint from May to frost if sheared after the first flush, gaura from June to October, corydalis lutea for four months in shade, and coreopsis 'Moonbeam' from June to September. In zone 7 and warmer, autumn sage blooms from April to November. All of them bloom longer if deadheaded, and our list of perennials that bloom all summer ranks the rest by how long they actually hold.

Can I plant perennials rated for a colder zone than mine?

Yes, and it is the safe direction to move. A zone 3 plant grows perfectly well in zone 6. The one caution is at the warm end: many cold-hardy perennials such as peony, delphinium, lupine, and bleeding heart need winter chill or cool summer nights, so they thin out in zones 8 and warmer even though the cold is no threat at all.

What perennials grow in full shade?

Hosta, astilbe, hellebore, epimedium, brunnera, lungwort, Solomon's seal, ferns, bergenia, Japanese forest grass, and in zones 7 and warmer cast iron plant and holly fern. Full shade means fewer than three hours of direct sun. Expect foliage to do most of the work, because deep shade limits flowering in nearly everything.

When is the best time to plant perennials?

Early spring and early fall, in that order of preference for cold zones. Spring planting gives the plant a full season to root before winter, which matters most in zones 3 through 5. Fall planting works well in zones 6 through 9 as long as it happens at least six weeks before the ground freezes so roots can establish.

How far apart should I space perennials?

Space them at their mature spread, center to center, for a solid mass, or at one and a half times that spread if you want each plant to keep a distinct shape. A 24 inch spread means 24 inch spacing, which works out to about one plant per four square feet. Crowding looks better in year one and causes mildew and division work by year four.

Which ornamental grasses stay small?

Blue fescue at 8 to 12 inches, Pennsylvania sedge at 6 to 8 inches, 'Hameln' fountain grass at 24 inches, prairie dropseed at 24 to 36 inches, and Japanese forest grass at 12 to 18 inches for shade. Avoid miscanthus and tall switchgrass in a small bed; they reach 6 to 8 feet and swamp everything planted near them.

Do creeping thyme lawns actually work?

Only in full sun with sharp drainage and light foot traffic, such as between pavers, along a path, or on a hot slope. Creeping thyme will not survive clay, shade, standing winter moisture, or the daily traffic of a real lawn. For a walkable shade ground cover, use Pennsylvania sedge or ajuga instead, and for moist sun use mazus.