Page 126 - Bexley SuDS DESIGN & EVALUATION

Detailed Design 9.10.3.3 Wetland & pond planting Autumn and winter planting of wetland

The biology of ponds and wetlands is similar,
but not identical. One definition suggests
plants often fails to establish well and they
that ponds have around 75% open water and
tend to be uprooted by water or wind. Plant
in spring or early summer wherever possible.
wetlands around 25%.

Where wetland plants are being used where
The planting requirements are very similar.
people are often present e.g. housing, visually
Wetland habitats are very sensitive to
invasive plants and therefore unless the SuDS
enhance acceptability by the community.
are part of an enclosed urban situation native attractive native plants can be selected to
Flag iris (Iris pseudacorus) and Purple
wetland plants should be used in planting
Loosestrife (Lythrum salicaria) are examples
proposals and should be obtained from an of plants that add attractiveness to waterside
accredited source with confirmation that the
planting.
aquatic nursery is free from alien and invasive
species. Wetland and pond planting design criteria:

Wetland plants can be divided into 3 ■ Selection of aquatic plants should
categories: normally be native, and a mix of emergent
■ emergent plants that tend to grow and spreading plants.

vertically around the edge and into the
■ In urban design some ornamental planting
water depending on its depth
may be justified but not where there is a
121 ■ spreading plants that tend to grow risk of direct links to the natural
horizontally around the edge and into the environment.
water depending on the depth

■ water plants that grow in the water
column either anchored by roots or free
floating.

These plants are usually planted at 5 or 8

plants per square metre or as a linear edge to
wetlands. Wetland plants grow vigorously in
spring and through the summer with growth
slowing as autumn approaches.

Design Note:
Reedmace (also called Bulrush or Typha latifolia) can seed rapidly on exposed mud edges.
This colonizing plant should be considered a potentially dominating weed until a diverse plant
community is established.

London Borough of Bexley SuDS D & E Guide © 2018 McCloy Consulting & Robert Bray Associates