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LOBELIA siphilitica
Commonly known as Blue cardinal flower
Clear blue
Further Reading....
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BlueClear blue
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Height60-120cm (24-48in)
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Spread30cm (12in)
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HerbaceousEarly in the year, typically January till end of March, herbaceous plants might be supplied in 9cm pots to ensure timely despatch.Clump-forming perennial with erect, leafy stems. Toothed leaves can be oval, broadly lance-shaped or oblong. They are 10-15cm (4-6in) long, light-green and softly hairy. Produces long-lasting, tubular, 2-lipped flowers 2.5-3.5cm (1-1½in) across
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Hardy - cold winterHardy in most places throughout the UK even in severe winters. May not withstand open/exposed sites or central/northern locations. Plant can withstand temperatures down to -15°C (5°F)
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Full sun
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Partial shade
LOBELIA siphilitica
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Additional FeaturesPests & DiseasesSlugs, leaf blotch.Place of originEastern USA.
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Flower ShapeRacemesDense racemes 10-50cm (4-20in) longTubular
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HardinessFully hardy
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Seasonal InterestSummer
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Soil ConditionsFertile moist well-drained soil
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Toxic - Category CHarmful if eaten(People & Pets)Skin irritant
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Herbaceous Plants - Video Collection
- Dividing Herbaceous Perennials - Video Tip ondemand_video
- Spring Planting Osteospermums - Video Tip ondemand_video
- Dividing Summer Perennials - Video Tip ondemand_video
- Dividing summer flowering Hemerocallis - Video Tip ondemand_video
- Summer propagation - Video Tip ondemand_video
- Self-seeding aquilegia - Video Tip ondemand_video
- Supporting Plants - Video Tip ondemand_video
- Dead heading meconopsis - Video Tip ondemand_video
- Dead heading Delphiniums - Video Tip ondemand_video
- Feeding herbaceous peonies - Video Tip ondemand_video
- Overpotting Problems - Video Tip ondemand_video
Lobelia - Care Guide
60-120cm (24-48in)
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30cm (12in) |
Useful extras...

Fertilisers & Feeds - Vitax
Q4 Pelleted Fertiliser
A useful fertiliser suitable for use on a wide variety of plants. Q4 provides all the nutrients and trace elements essential for vigorous growth, abundant flowering and ripening of fruit.
3 options from £6.00

Fertilisers & Feeds - Empathy
Rootgrow mycorrhizal fungi
Recommended by the RHS. Contains Rootgrow™ mycorrhizal fungi. Suitable for all trees and shrubs (except rhododendrons, azaleas, heathers, cranberries and blueberries)
2 options from £6.00

Fertilisers & Feeds - Empathy
All-purpose Seaweed Stimulant
All-purpose organic concentrated seaweed feed that is a ready to use, derived from sustainable harvested kelp, that can be used on all outdoor and indoor plants, except acid loving plants.
Perfect used in conjunction with Rootgrow™.
Only £7.50

Vermin & Pest Control
Slug Pellets
Slug killer blue mini pellets are easy to use and give effective control of slugs and snails.
Ideal in garden, conservatory or greenhouse.
Only £6.50

Vermin & Pest Control
Copper Tape
Quick and easy way to repel slugs and snails from your pots with this adhesive copper tape.
Only £7.50