5.1-5.3 Aquatic plants COPY Flashcards
5 Categories of aquatic plants
Oxygenators (submerged) - Hottonia palustris (water violet)
Lagarosiphon major (goldfish weed)
Deep water - grow rooted in the soil base of a pond (that is 30-90cm deep) -
Nymphaea sulphurea
Nuphar lutea
Surface floating - Hydrocharis morsus-ranae
Stratiotes aloides
Marginals - grow in shallow water with water over the crown and roots submerged foliage above water surface. Planted in containers or in puddled clay
Iris pseudacorus
Caltha palustris
Bog plants in situ directly in the soil over the membrane - must be constantly moist. Will grow on temporarily waterlogged soil
Bog plants Gunnera manicata
Acorus gramineus ‘Variegatus’
Oxygenators
Hottonia palustris (water violet)
Lagarosiphon major (goldfish weed) - considered a non-native invasive plant
Deep water
Nymphaea sulphurea
Nuphar lutea
Surface floating
Hydrocharis morsus-ranae
Stratiotes aloides
Categories
Features
Oxygenators: submerged plants that help oxygenate the water and keep in clear of algae by competing for nutrients in the water
Deep water: rooted in the soil. Usually decorative and help reduce algae by cutting down on light
Surface floating: also cut down on light, but care must be taken not to let them smother and kill oxygenators
Marginals: grow in shallow water. Can provide habitat and protection for wildlife
Bog plants: thrive in moist soil - as above
Marginals
Iris pseudacorus
Caltha palustris
Bog plants
Gunnera manicata
Primula japonica
Acorus gramineus ‘Variegatus’
Name
Hyrdrocharis morsus-ranae
surface floating
Name
Stratiotes aloides
Surface floating
Name
Lagarosiphon major
Oxygenator
Name
Carex elata ‘Bowles’s Golden’
Name
Nuphar lutea
Deep water
Planting:
timing
method
principles
Usually between May and August
Deep water, submerged and marginal plants are planted 1. in soil in bed of pond or 2. in containers
50% of surface should be covered with foliage from deep water and floating plants to restrict algae growth. If coverage is greater than 70%, light levels are insufficient for submerged plants
Division
Best divided after flowering when in active growth - spring
Remove container avoiding damage to liner.
Remove plant from container
Trim roots or tease roots through mesh sides if necessary
Remove compost
Separate/cut the plants into sections to include growing point and roots
Remove DDD material
Retain most healthy and vigorous setions
Maintenance of water features
Lower plants (deep water aquatics or marginal) by removing bricks
Winter:
Ensure a small area of the pond remains ice free (trapped methane can be fatal to fish). Use hot pan to melt section or cover small ponds)
Remove leaves/debris from pond/bog areas
Restock with new plants and lift and divide overcrowded plants after flowering
feed container planted with slow release aquatic fertilisers
Summer:
Remove dead flower heads from marginals/bog plants
Top up water levels if required (rainwater)
Weed control on surface of water and in bog garden
Cut back over vigorous oxygenators
Remove excessive growth of floating weeds
Autumn:
Remove dead plant material and organic matter (netting helps)
Cut back oxygenators/marginals
Remove non-hardy plants for overwintering
Pond cleaning (draining first) should be done in autumn
Spring
May-August for new planting
Divide and re-pot eg Nymphaea species or Iris
Feed water lilies
Problems in ponds
Algae: caused by high nitrate levels + excess sun
Control: increase shade (to 50-60%) but at least 33% and avoid tap water (nitrates). Filter the pond and empty no more than once every couple of years to maintain a healthy balance.
Barley straw can act as filter - bale or straw pads added in spring and left for 6 months when blackened. Algaecides clear water temporarily
Blanket weed: form of algae best removed by hand. Filters (eg UV clarifiers) kill the algae cells
Invasive plants eg. Lagarosiphon major pull out by hand
When pulling out weeds leave on side of pond to allow pond life to re-enter the pond
Ice: causes harm to fish and plant life - air holes allow gaseous exchange. Melt a hole or keep a ball floating in the pond
Method for planting (baskets)
- Line container with hessian
- Fill with loamy compost (no organic matter and excessive fertiliser - especially N) Slow release aquatic fertiliser is inserted into container in spring. If garden soil is used must be free of fert, pesticides, weeds, pests and diseases
- Insert and firm in plant and top with pea shingle to 2cm
- The container should be well watered and lowered into the pond (may be lowered using ropes and 2 people)
- Use bricks blocks if required to raise to right level
