Preparing the ground before planting is often best as the ground may require preparation prior to planting to prevent competition from the existing weed species. Tall vegetation should also be cut back and weeds such as docks and nettles should be treated with a broad spectrum herbicide suitable for use near water.
These aquatic plants can be divided into four planting zones. These zones are known as Bog plants, Marginal’s, Emergents and Submergents/Oxygenators.
This needs to be taken into considerations when selecting the species of plant for the project areas, as they require differences in planting depth, water levels and if the water should be flowing or standing (rivers or ponds).
These are species that grow in waterlogged or seasonally inundated areas rather than within the water column. Recommended planting density of 20 plants per Sq.M of small wildflower plugs (27cc).
Marginal plants can be planted at, or just above, the water’s edge at a maximum planting depth of 350mm. We recommend a planting density of 8 plants per Sq.M of 7cm plugs. Some species will prefer to be in drier conditions, whilst others prefer the damp, boggy soil at the waters edge.
Emergent plants should be planted in the water column to a planting depth of 0-500mm (the roots then grow deeper). If the area is likely to dry out and the overall depth is less than one meter, we would recommend avoiding aggressive emergent species such as typha (bullrush) and Phragmites (common reed). Emergents are important for greater photo-remediation capacity, such as reeds and bull rush but these can eventually dominate an area if they are not maintained. We recommend a planting density of 8 plants per Sq.M.
These species include floating plants such as water lilies and oxygenating plants for example pond weeds. These plants should be totally submerged or floating in the water column and we recommend between one and four plants per Sq.M. Most oxygenating species are sold in leaded bunches that can just be dropped in the water and others, such as bog bean, creep along the surface and can be dropped in as bare root plants. Water lilies are sold in baskets, which should be submerged under the water up to 1.5M depth which allows the leaves to float at the surface.
Advantages and uses of Aquatic plants:
- Reedbeds – Treatment reedbeds & habitat creation
- To improve water quality in lakes and ponds
- To improve biodiversity
- Bioengineering applications
- Habitat creation, including protected species
- Aesthetic reasons
- SUDS – Sustainable Urban Drainage Systems