About
Sour Grapes' is an erect perennial to 60cm in height, with lance-shaped leaves and dense panicles of tubular, two-lipped flowers blending purple and blue shades, whitish within the throat.
About the genus
Penstemon may be deciduous or evergreen perennials or subshrubs, with simple, narrow leaves and racemes or panicles of bell-shaped or funnel-shaped flowers in summer and early autumn
Growing conditions
SunlightFull sun, Partial shade
Soil typeChalk, Loam, Sand
Soil pHAcid, Alkaline, Neutral
Soil moistureWell-drained
AspectWest-facing, South-facing, East-facing
ExposureExposed, Sheltered
UK hardinessH4
Plant details
Plant typeHerbaceous Perennial
HabitClump forming
FoliageSemi evergreen
Height0.5-1 metres
Spread0.1-0.5 metres
Time to full height2-5 years
Suggested usesCottage and informal garden, City and courtyard gardens, Coastal, Gravel garden, Wildlife gardens
Care notes
CultivationGrow in fertile, well-drained soil in full sun or partial shade. In cold areas, protect plant overwinter with a dry winter mulch. See penstemon cultivation for further advice
PruningDeadhead after flowering to maintain vigour. Then cut back to base in early spring
PropagationPropagate by softwood cuttings in early summer or semi-hardwood cuttings in midsummer. Propagate by division in spring
Pest resistanceMay be susceptible to slugs, snails, glasshouse red spider mite, and leaf and bud eelworms
Disease resistanceGenerally disease-free