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We have combined these two powerful search tools into a single Find a Plant service searching over 250,000 plant records.
Virtually all of the features of the old searches are still available and in addition we have added several new features to create a more comprehensive and user friendly search experience.
When using this search
Search by plant name, key attributes or both to find plant details and a list of
AGM plants have been through a rigorous trial and assessment programme. They are:
This plant will provide nectar and pollen for bees and the many other types of pollinating insects.
It is included in an evolving list of plants carefully researched and chosen by RHS experts. Divided into 3 groups these lists, linked below, are maintained by a team of RHS staff and are reviewed annually.
the RHS today and get 12 months for the price of 9
Other common names
scarlet beard tongue Hartweg penstemon
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
P. hartwegii is a bushy semi-evergreen perennial to 70cm in height, with narrow foliage and panicles or racemes of slender bright crimson flowers 4cm in length, marked white in the throat and borne on purple stems
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
Aspect South-facing or East-facing or West-facing
SoilChalk, Loam, Sand
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow in fertile, well-drained soil in a sheltered position in full sun or partial shade. In cold areas, protect plant overwinter with a dry winter mulch
Propagate by softwood cuttings in early summer or semi-hardwood cuttings in midsummer. Propagate by division in spring
Suggested planting locations and garden types
Flower borders and beds
City & Courtyard Gardens Cottage & Informal Garden
Pruning Deadhead after flowering to maintain vigour, then cut back to base in winter
Pests May be attacked by slugs, snails and chrysanthemum eelworms
May be subject to a downy mildew
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
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