53 hardy perennials for the garden border
The catalogue has four flowering shapes — cluster, cup, daisy and spike — plus the herb sprig, and 53 species carry one of them together with a coldest night of -15 °C or below. Everything the catalogue records about them is in the row: water interval, light tier, humidity tier and that minimum.
In the table, watering runs from 3 to 14 days at medium light; 1 of the 53 want humid air.
| Plant | Water | Light | Humidity | Temperature or hardiness |
|---|---|---|---|---|
| RoseRosa | every 3–6 days | Direct sun | Medium | down to -15°C outdoors |
| Crocus | every 5–10 days | Direct sun | Low | down to -20°C outdoors |
| DaffodilNarcissus | every 5–10 days | Direct sun | Low | down to -20°C outdoors |
| PeonyPaeonia lactiflora | every 5–9 days | Direct sun | Medium | down to -25°C outdoors |
| TulipTulipa | every 5–10 days | Direct sun | Low | down to -20°C outdoors |
| OreganoOriganum vulgare | every 7–14 days | Direct sun | Low | down to -20°C outdoors |
| Purple coneflowerEchinacea purpurea | every 7–14 days | Direct sun | Low | down to -30°C outdoors |
| SageSalvia officinalis | every 6–12 days | Direct sun | Low | down to -15°C outdoors |
| ThymeThymus vulgaris | every 7–14 days | Direct sun | Low | down to -15°C outdoors |
| agapanthusAgapanthus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| alumrootsHeuchera | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Aquilegia vulgaris | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| baby's-breathGypsophila paniculata | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| balloon flowerPlatycodon grandiflorus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| barrenwortsEpimedium | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| beardtonguesPenstemon | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| bellflowersCampanula | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| black-eyed SusanRudbeckia hirta | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| BlanketflowersGaillardia | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Brunnera | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| CatchfliesSilene | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Christmas-roseHelleborus niger | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Common ChrysanthemumChrysanthemum × morifolium | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| common yarrow complexAchillea millefolium | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| DaisyBellis perennis | every 4–8 days | Bright | Medium | down to -20°C outdoors |
| dayliliesHemerocallis | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Dianthus caryophyllus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| fall phloxPhlox paniculata | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| false goat's beardsAstilbe | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| foamflowersTiarella | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Forget-me-notsMyosotis | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Garden Lady's-mantleAlchemilla mollis | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Garden LobeliaLobelia erinus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| goldenrodsSolidago | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| HyacinthHyacinthus orientalis | every 4–8 days | Bright | Medium | down to -15°C outdoors |
| Large-leaved lupineLupinus polyphyllus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| larkspursDelphinium | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Lemon balmMelissa officinalis | every 4–8 days | Bright | Medium | down to -20°C outdoors |
| lungwortsPulmonaria | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Monk's-hoodAconitum napellus | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Oriental PoppyPapaver orientale | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Perennial CandytuftIberis sempervirens | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| PokersKniphofia | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| poppy anemoneAnemone coronaria | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| PrimrosesPrimula | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| purple rock cressAubrieta deltoidea | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| SoapwortsSaponaria | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| TickseedsCoreopsis | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| vervainsVerbena | every 5–10 days | Bright | Medium | down to -15°C outdoors |
| Wild pansyViola tricolor | every 4–8 days | Bright | Medium | down to -15°C outdoors |
| common hibiscusHibiscus syriacus | every 7–14 days | Bright | Medium | down to -20°C outdoors |
| FoxgloveDigitalis purpurea | every 4–8 days | Medium | Medium | down to -20°C outdoors |
| Lily of the valleyConvallaria majalis | every 5–10 days | Medium | High | down to -30°C outdoors |