Egeria densa
Brazilian pondweed
A vigorous aquatic perennial, with branching stems to 90cm long, with whorls of fine, linear leaves all along the stems. Stems form dense mats on reaching the surface of the water. Small white flowers borne on thin stems are held just above the water in late spring, and sometimes again in autumn. Usually sold as an aquarium plant, can be invasive outside this environment
Size
Ultimate height
0.5–1 metresTime to ultimate height
1–2 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | White | Green | ||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | White | Green | ||
| Winter |
Position
- Full sun
Aspect
Exposure
Hardiness
H2Botanical details
- Family
- Hydrocharitaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Submerged, Matforming, Floating
- Name status
Correct
- Plant range
- S USA, C & NS America
How to grow
Cultivation
This plant is listed on Schedule 9 of the UK Wildlife & Countryside Act (Northern Ireland) as an invasive non-native species. Although not banned from sale, it is an offence to plant or cause these to grow in the wild IN NORTHERN IRELAND or the REPUBLIC OF IRELAND. Gardeners possessing them should undertake measures to control them. See RHS advice on invasive non-native species for further information
Propagation
See cultivation notes
Suggested planting locations and garden types
Pruning
Trim regularly to encourage fresh growth
Pests
May be susceptible to snails or fish who nibble young shoots
Diseases
Generally disease-free
Get involved
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