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PERSICARIA amplexicaulis 'Blackfield'
Commonly known as Knotweed, Polygonum
Slender flowers in deep red-black. A smouldering beauty
Further Reading....
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Semi-evergreenKeeps some of its foliage all year, and will drop some leaves as well.Ovate, lance-shaped, pointed, mid-green leaves to 25cm (10in) long, slightly puckered.
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RedDeep red black
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HeightTo 1.2m (4ft)
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SpreadTo 1.2m (4ft)
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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.Robust, clump-forming perennial
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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
PERSICARIA amplexicaulis 'Blackfield'
- Details
- Description
- Mature Size
- Tips and Advice
- Goes Well With
- Planting Combinations
- Other Suggestions
- See Also...
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Additional FeaturesPests & DiseasesNonePlace of originGarden originResistant to honey fungusThese plants have little or few problems with honey fungus.
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Flower ShapeBell/LanternNarrowly bell-shaped 5mm (¼in) longSpikesLong-stalked narrow spikes to 10cm (4in) long
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HardinessFully hardy
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Seasonal InterestSummer
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Soil ConditionsTolerates allAny moist soil.
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WildlifeBee friendlyRabbit Resistant
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
Persicaria - Growing Guide
to 1.2m (4ft)
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to 1.2m (4ft) |









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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