R2114 exam question examples Flashcards
Name seven structural features on a glasshouse + description/function
Ridge
- joins both sections of glasshouse roof.
- provides strength to roof.
Ridge vent
- allows warm air to escape
- provides adequate ventilation
Internal framework
- provides strength to roof and to sides of structure.
Gutter
- to remove and harvest rainwater
Louvred vent
- allows cool air to enter structure
Cladding
- horticultural glass or twin-walled polycarbonate sheeting
Side vent
- allows cool air to enter the glasshouse (usually louvre)
Name three structural features on a polythene tunnel + description/function
Polythene cladding
- skin/polythene, with UV stabiliser to extend life of polythene.
Wooden frame doors
- provides ventilation in a walk-in tunnel
Netlon skirt/side vent
- to provide additional ventilation
Seven environmental factors that a grower has to consider when growing crops under protection, plus how each can be manipulated
Air temperature
- raised by use of heating
- lowered with vent, shading, damping down
Soil temperature
- warm with warming cables or hot pipes in glasshouse beds/benches
Availability of water
- provision of irrigation overhead or ground level, through pipes, seep or drip hoses
- good soil texture, structure and depth help to hold moisture
Relative humidity
- raised by damping down, use of humidifier
- lowered by good ventilation
Carbon dioxide concentration
- from good air movement through ventilation
- enriching atmosphere with CO2 gas to increase
Natural light
- glasshouse design and orientation will dictate how much light enters
- cleanliness of glass and lack of shading allows more light in
Air movement
- affected by providing adequate ventilation through layout and size of vents
- plant spacing will also affect
Pests and symptoms of decorative pot plants in protected environment x2
Vine weevil:
- larvae eat roots, plant becomes stunted, wilts, becomes chlorotic
- adults make irregular notches in leaves
Glasshouse whitefly:
- distortion of growing tip
- honeydew and sooty mould present
Diseases and symptoms of decorative pot plants in protected environment x2
Botrytis (Grey Mould):
- fuzzy, grey mould on buds, flowers, leaves, non-woody stems and fruits
Powdery mildew:
- dry, powdery, grey-white fungal bloom on upper surface of leaves, shoots and flowers
- can lead to red blotches on leaf which then curls upwards
Method of cultural control for a pest (+ example of pest)
Two-spotted spider mite:
- controlled culturally by increasing humidity in a protected environment.
- damping down concrete surfaces with water or misting the atmosphere.
Management of a NAMED fern in domestic building, under:
- Aerial environment
- Re-potting
- Watering
Adiantum raddianum (maidenhair fern)
Aerial environment:
- stable temp of 18-22 deg C
- avoid draughts
- RH of 60-80%, maintained by standing pot in larger tray of moist grit (water level always below base of pot!)
- or humidifiers (for RH)
- diffused light is best.
Re-potting:
- when pot-bound, in the spring
- prefer to be kept slightly under-potted, so never over-pot!
- remove any damaged/diseased fronds, and tease out roots a little if very pot-bound
- use high organic content potting media, planting no deeper than previous level
- firm in to remove large air pockets, but don’t compress too much.
Watering:
- keep compost moist at all times but never waterlogged (rotting!)
- don’t allow to dry out completely
- reduce watering in winter
- water from below using drip tray/capillary matting to avoid water on leaves (scorching)
- use rainwater if possible.
One method of forcing a bulb + bulb example
Narcissus ‘Tete-a-Tete’
- ideally choose a glazed bowl for display, and place a crock over the central base hole
- prepared bulbs potted in early autumn (start of Oct) into moistened bulb fibre compost
- arrange bulbs close together, but not touching, with growing tips showing just above compost
- place bowl in cool, dark, moist environment (e.g. cold garage, fridge, shady N-facing wall) at 4 deg C, for 8-12 weeks.
- this encourages root and flower bud development
- bowl then placed in well lit location at 10-15 deg C for 4 weeks, before flowering commences.
One named disease of bulbs, plus symptoms and control
Basal rot/bulb rot of Narcissus
- pinkish white fungus between affected scales and on base plate in stored bulbs
- when bulbs are planted the foliage may yellow prematurely and not flower.
- no chemical control, but planting of resistant cultivars (e.g. Narcissus tazetta) is beneficial
- also preferable not to store damaged or soft bulbs, to avoid the disease.
Distinct materials and characteristics used in manufacture of plant containers
Terracotta:
- porous, need to water more regularly
- attractive
- heavy to move esp. when watered
- may not be frost-resistant
Plastic:
- wide range of shapes, sizes and colours available
- lightweight - easy to transport and handle
Natural/reconstituted stone:
- difficult to clean
- durable - lasts a long time without need to replace
Steel & aluminium:
- marks easily - problem in prestigious locations
- expensive compared to other materials (e.g. plastic)
Wood:
- good for use as larger pots and planters
- natural, attractive look
- prone to rotting
- heavy when planted!
Six distinct protective structures used in crop production, propagation or display
Glasshouse
Conservatory
Polythene tunnel (walk-in)
Low tunnel
Cold frame
Cloche
Four horticultural uses for a Glasshouse (six points in total!)
- propagate a range of plants (e.g. Cyclamen persicum)
- growing main season crops (e.g. Solanum lycopersicum)
- overwintering plants
- display house for specimens
- used as heated or non-heated environment to grow vegetable or ornamental plants,
e.g. tomatoes, cucumbers, poinsettias, cyclamen - crops can be grown on benches/staging, or on ground using a hydroculture system.
Four horticultural uses for a walk-in Polythene Tunnel + 2 limitations:
- grow short-season crops, (e.g. Lactuca sativa)
- grow celery, strawberries, raspberries, peppers and lettuce;
- plant propagation;
- overwintering plants
- usually non-heated, but can be heated if required
Limitations:
- less flexible growing structure compared to a glasshouse
- potential of growing season is shorter and retains high level of humidity
Three horticultural uses for a Cold Frame
- propagating hardy plants
- growing bedding plants
- hardening off plants (e.g. Impatiens walleriana)
FOUR horticultural uses for a Cloche
- protecting early season row crops;
- starting off French/Runner beans until established;
- plant protection over winter;
- protects crops (e.g. lettuce, strawberries) from environmental conditions, e.g. frost, rain, wind.
Two reasons why adequate ventilation is essential to successful growing under protection
To maintain optimum air temperatures for growing:
- if temps too high = soft growth that is susceptible to P&D damage, lower yields
- if temps too low = stunted growth, reduced flower production, lower yields.
To maintain ambient levels of carbon dioxide to enable photosynthesis to take place:
- poor ventilation = temporary depletion of CO2 in boundary layer around leaf surface, resulting in reduction in growth.
Describe one named method of ventilation
Forced draught or Fan ventilation:
- extractor fans installed at one end of structure
- opening constructed at other end
- as hot, moist air is extracted from structure by fans, cooler air enters through opening
- air speed entering structure is slow due to large surface area of opening
- range of ventilation rates can be achieve depending on number of fans, or speed of fan rotation (this is controlled by thermostat installed within structure).
- Another example is natural ventilation such as vents and louvres.
Cladding: describe properties of Horticultural Glass
- good natural light entry for long period of time
- easily broken - risk hazard
- very heavy
- long life span
- retains heat well
Cladding: describe properties of Polycarbonate
- usually twin-walled, which traps air
- good insulator/heat retention
- lightweight, easy to handle
- can be cut to shape with a saw
- doesn’t break easily
- more expensive than glass
- good light transmission but may deteriorate over time due to acid rain
Cladding: describe properties of Polythene Film
- limited life span (4-5 yrs)
- creates condensation which results in high RH environment
- doesn’t retain as much heat as glass
- good light transmission but is reduced due to condensation
- susceptible to wind damage and snow loading
- goes brittle/deteriorates over time due to dust and UV rays
- less expensive than glass
Cladding: describe properties of Acrylic Sheets
- can be obtained in limited sizes
- discolours over time
- only limited number of thicknesses available
Cladding: describe properties of Horticultural Fleece
- reduces light levels which results in a shade effect
- doesn’t retain heat
- useful for frost protection for short periods of time
Name five different fuels used to heat a protected structure
Gas
Oil
Electricity
Bio-fuel
Paraffin
Two ways of distributing heat around a protected structure
By air:
- e.g. fan heater in one corner
- polythene ducting which distributes heat evenly
By water:
- network of pipes running length of glasshouse (like central heating)
- circulating pump ensure water runs along all the pipework
- N.B. - warm air rises, so heat source needs to be low down to ensure even heat distribution!
Heating a structure - how can efficiency be achieved?
Efficiency depends on the RELIABILITY and EFFECTIVENESS of the heat source,
- Combined with the ability to distribute heat around structure QUICKLY.
This is to ensure the system can respond to any temperature change in the structure.
- Low thermal inertia provides a quick response!
Financial efficiency also important - i.e. maximum heat for minimal cost.
