Join the RHS today and support our charity
Free personalised gardening advice
RHS members get reduced ticket prices
RHS members get free access to RHS Gardens
Reduced prices on RHS Garden courses and workshops
020 3176 5800
Mon – Fri | 9am – 5pm
Make a donation
I have forgotten my password
Keep me signed in
Register for free to receive our newsletters, add comments to blogs/articles and to save content.
See what events are on near you and browse your bookmarked pages.
Don’t miss out - book in advance and save
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
lobelia 'Hadspen Purple'
Lobelia syphilitica 'Hadspen Purple' Lobelia × gerardii 'Hadspen Purple'
Lobelia 'Hadspen Purple' Lobelia 'Hadspen Royal Purple'
Lobelia can be annuals, perennials or shrubs, with simple leaves and showy 2-lipped flowers that may be solitary or in racemes or panicles
'Hadspen Purple' is a semi-evergreen perennial, up to 60cm in height, with upright stems bearing ovate to lance-shaped, purple-flushed, light green leaves and terminal racemes of two-lipped, bright purple flowers from summer into autumn
Toxicity Ingestion may cause severe discomfort
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 or North-facing
Exposure Sheltered or Exposed
MoistureMoist but well-drained
SoilSand, Loam, Clay, Chalk
pHAcid, Alkaline, Neutral
Time to ultimate height
Plant in deep, fertile, reliably moist soil in sun or partial shade. Feed every 2 weeks with a balanced liquid fertilizer until midsummer and a low nitrogen fertilizer for the remainder of the growing season. Protect the crown of the plant during winter with a thick, dry mulch
Divide large clumps of plants every second year in spring
Suggested planting locations and garden types
Flower borders and beds Low Maintenance Wall-side Borders Garden Edging
City & Courtyard Gardens Coastal Cottage & Informal Garden Wildlife Gardens
Pruning Cut down faded flower spikes in autumn
Pests Slugs may be a problem
May be subject to crown rot and a virus
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
lobelia 'Hadspen Purple'
Buy from £7.99 at the RHS Plants Shop
We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.
Join the RHS today and get 12 months for the price of 9