Myriophyllum proserpinacoides

RHS Plant Profile

parrot's feather

Other common names

diamond milfoil, smilax

Synonyms

Myriophyllum brasiliense, Myriophyllum proserpinacoides

Aquatic

This plant is listed as an invasive non-native species in the UK – see Cultivation section for details An aquatic perennial with branched stems bearing whorls of finely divided leaves, forming dense mats at the water surface, with emergent shoots about 20cm high

Position

Full sun

Soil Types

Loam

Max Height

Up to 10 cm

Max Spread

1-1.5 metres

Size

Time to Maturity: 5–10 years
Max Spread: 1-1.5 metres
Max Height: Up to 10 cm

Growing Conditions

Loam

Moisture: Poorly–drained
pH: Acid or Alkaline or Neutral

Position

Full sun

Aspect: South–facing or West–facing
Exposure: Exposed or Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

H1A: under glass all year (>15C)
H1B: can be grown outside in the summer (10 - 15)
H1C: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20): H4

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Haloragaceae
Native to GB/Ireland: No
Foliage: Deciduous
Habit: Submerged
Genus: Myriophyllum can be submerged or marginal aquatic rhizomatous perennials, with finely dissected submerged leaves and small or minute flowers, solitary or in spikes from the leaf axils
Name Status: Synonym

How to Grow

Cultivation

This plant is listed on Schedule 9 of the Wildlife & Countryside Act (1981), the?GB?Non-Native Species Secretariat?list of Species of Special Concern?and the?EU list of Invasive Alien Species of Union Concern (applies in NI).?It?should?not be planted or caused to grow in the wild?in?the?UK.?It is also banned from sale, and gardeners who already have it should take steps to control it.?See RHS advice on?invasive non-native species?for further information

Propagation

See cultivation notes

Pests

See cultivation notes

Diseases

See cultivation notes