RHS level 2 R2112, Alpines, Aquatics Flashcards
Understanding choice, establishment and maintenance
What is meant by true alpines?
Plants from high altitudes where certain conditions exist.
Protection from frost and winds under snow, not wet and cold in winter, very free draining soil, plenty of sun and fresh, constantly moving air in summer.
What is meant by rock garden plants?
Rockery perennial. Dwarf herbaceous perennial suitable for growing in a rock garden. Can include: True alpines Low growing herbaceous plants Slow growing ground cover plants Dwarf shrubs Dwarf bulbs.
Describe the soil characteristics for alpine/rock gardens.
Free draining Good aeration Ability to hold moisture Low nutrient content Free of weeds, pests, diseases.
Describe the soil preparation for alpine/rock gardens.
Clear the area of weeds and dead foliage and unwanted plants.
Can create a slope by grading or terracing.
If site is level and you need to improve drainage then remove 12in of top soil then put down 6in layer of rubble, top this with a mixture of loam, sand, grit, leaf mould and peat substitute about 9-12in.
Or can add grit, sand and peat substitute to top soil.
Cultivate soil and rake the bed, moulding into required shape
Describe the routine maintenance for alpine/rock gardens.
Weeding- reduce the competition for slow growing alpines.
Top dressing- with grit, needs to be maintained especially on slopes. Also helps minimise the effect of heavy rain on the soil surface.
Trimming and pruning- removing dead, damaged, diseased parts of dwarf shrubs. Some plants such as Aubretia benefit from a hard cutting back (about half) to keep compact and promote new growth to flower.
Winter protection- some plants require protection from cold and wet. Can be done with panes of glass propped up over plants.
Describe possible pests and diseases for alpine/rock gardens.
Most alpines are problem free however if fed too much soft growth can attract aphids.
Slugs and snails- grit and drier conditions can discourage them.
Ants - occasionally form nests under cushion forming plants.
Fungal diseases- poor ventilation and/or foliage gets wet.
Describe the choice of containers for alpine/rock garden container displays.
Usually natural material like stone, earthenware, wood:
Troughs
Sinks, often coated with natural looking substance e.g. hypertufa.
Containers made of hypertufa
Hollowed out logs/ trunks.
Describe the characteristics and preparation of growing medium for alpine/rock garden container displays.
Free draining, good aeration, ability to hold moisture, appropriate pH, low nutrient content, free of weeds pests and diseases.
Standard potting mix plus a third as much again of stone chippings 6-9mm.
Cover drainage holes at bottom of container with crocks.
Pour in a quarter of the depth with chippings/gravel.
Cover this with a layer of fibrous peat substitute and finish with the compost mix.
Position and bed in pieces of rock or tufa as the container is filled to simulate a small scale rock garden.
Water thoroughly, allow to drain, then plant up.
Give two examples of aquatic floating plants and describe their use in a pond.
Stratiotes aloides
Hydrocharis morsus-ranae
Used to discourage algae by covering the pond surface and reducing light levels.
They mustn’t be over vigorous and should be removed as more ornamental plants become established.
They have no anchorage.
Give two examples of bog plants and describe their planting and establishment.
Gunnera manicata
Primula japonica
To prepare a big garden, dig hole of minimum 45cm deep with sloping sides.
Line with plastic and puncture it with a fork.
Put a layer of gravel at the bottom.
Refill with soil and cover with mulch.
Vigorous growers should be confined to sunken containers.
Give two examples of marginal plants and describe their planting and establishment.
Iris laevitiga
Caltha palustris
Most marginals require 8-15cm over their crowns. More vigorous/deep marginals should be at least 30cm deep.
If planting in containers give a minimum size of 23cm diameter.
Soil should be low in nutrients, heavy loam, unmanured, seive out organic matter.
Give two examples of deep water plants and describe their planting and establishment.
Nymphaea alba
Nymphoides peltata
These are grown in aquatic containers (mesh pots lined with Hessian) or planting beds (edged shelves filled with soil/compost).
Deep water plants in containers should be soaked well before immersion, with gravel added to surface to prevent soil floating out.
Position them shallowly in the water to start with so the leaves float on surface and photosynthesise.
When growth has begun they should be lowered further into the water until they reach the desired depth.
Describe the annual maintenance of a garden pond.
Structural repairs- liner repair, patches. Concrete ponds, filler and sealant.
Adjust levels.
Stabilise surrounding stones.
Maintenance of water quality- discourage algae by using barley straw and leaf nets to reduce nutrient content.
Removal of blanket weed using rake or sticks.
Clean pond out, remove rotting vegetation in the autumn.
Check pH is around 7.
Autumn and winter care - remove tender plants and place in a bucket in a frost free place. Thin plants. Cover with net. Reduce overhanging plants. Check or drain pump. Prevent ice forming.
Plant maintenance- Feeding? Division, repotting, propagation, dead heading. P&D control, weeding.
