RHS Level 2 Certificate

Week 14 – Prize Quiz and houseplants

Learning objectives

7. Understand the care of plants in an interior situation. 7.1 Describe the environmental factors that must be taken

into account when displaying plants inside domestic buildings.

7.2 Describe the choice of suitable containers and growing media for houseplants.

7.2 Describe the management of one fern (Adiantum raddianum), one foliage (Ficus benjamina) and three seasonal flowering plants (Euphorbia pulcherrima, Kalanchoe blossfeldiana, and Saintpaulia ionantha) under the following headings: potting; feeding; watering; deadheading; re-potting; pest and disease identification and control.

Prize Quiz

Twenty Questions – 30 minutesTest conditions pleaseThree prizes

Answers

1. (d) 2. (c) 3. (b) – because it warms up quickly in spring and has a loose texture for the carrots to grow into without forking. 4. (a) 5. (b) and (d) 6.(b) 7. (c) 8. Green Manure 9. Nitrogen – chlorophyll, green leafy growth; Phosphorous – essential for root growth; Potassium – essential for flowers and fruit; Calcium – essential for cell walls. 10. Foliar feed is sprayed onto the leaves. 11. Iron deficiency 12. (c) 13. (b) 14. (b) and (d)

15. (d) 16. (d) 17. (b) 18. (c) 19. (b) 20. 46°C and five minutes

Containers

Without the need to survive outdoor conditions the choice is endless.

Must have drainage holes though Stand an ordinary plastic plant pot on a layer

of gravel or leca if you have a planter without drainage holes

Could use a self watering container Remember the rate of drying out of the

growing media will be affected by the material chosen.

Environmental factors indoors

Humidity – much drier than most plants prefer

Light – may be limited, or too much (as on a south facing window sill in summer)

Temperature – day to night fluctuations and maximum and minimum may not be ideal

Water – specific plants have specific requirements; but all need watering

The Environment

Each plant’s needs will depend on where it originates – a jungle or a desert etc.

Light – most like bright but diffuse light; cacti are fine in direct sun.

Temperature – requirements vary, but large fluctuations are often a problem. Avoid draughts.

Humidity – needs vary; can be provided by misting; a gravel tray; grouping plants together.

Feeding and watering

Liquid feed is best, as it gives control. Controlled release is good for large plants.

As a rule of thumb, feed fortnightly in spring and summer and monthly otherwise.

Use a general purpose feed unless a specialist one is available, e.g. for orchids.

Watering – needs vary, as a guide water only if the compost feels somewhat dry to the touch. Water hairy leaved and succulent plants from below.

Routine Care

Remove any dead or diseased plant material immediately.

Dead head or remove spent flower stalks.

Treat pests and diseases as soon as seen.

Dust regularly – dust reduces photosynthesis.

Re-potting – not too often for flowering plants, every 2 years.

Pests and diseases

Aphids, whitefly and other sap suckers – weaken the plant, spread virus and excrete honeydew. Use fatty acid spray or a suitable systemic insecticide designed for houseplants.

Downy Mildew – encouraged by cool, damp conditions. Remove affected parts and raise the temperature.

Powdery Mildew – avoid water stress; treat with suitable systemic fungicide.

Sooty Mould – grows on honeydew, so control sap suckers. Can be removed with a damp cloth.

Addiantum raddianum

Jungle dweller Moderate light, no direct sun Moderate to high humidity – 60 to 80RH.

Stand on a gravel tray or mist. Warm conditions - 18°C or more Avoid draughts as they will cause the leaves

to go brown. Feed fortnightly when growing.

Ficus benjamina

A tree grown as a houseplant – they can outgrow their space, but take some time to do so.

Bright diffuse light, warmth and moderate to high humidity.

Water when dry and reduce watering in cool conditions.

Feed fortnightly when growing. Susceptible to scale insects and mealybugs.

Euphorbia pulcherrima

A Mexican shrub. Likes bright light, warmth (no fluctuations) and

moderate to high humidity. Keep out of draughts.

Feed monthly. Water when the surface of the compost is dry – do not overwater.

Will need 14 hours of dark for 6-8 weeks to initiate flower buds and colour the bracts.

Prone to whitefly

Kalanchoe blossfeldiana

Strong sunlight is fine. Low humidity and moderate to high

temperature. Feed every three weeks Water when compost surface is dry. Susceptible to aphid attack and to botrytis if

the conditions are too humid or it is overwatered.

Needs 15 hour ‘nights’ for 30 days in September to bloom at Christmas.

Saintpaulia ionantha

Good light, moderate warmth and moderate to high humidity.

Feed fortnightly in summer and spring with an African Violet feed. Lack of feeding leads to no flowers.

Water from below when the compost is just dry. Flowers best if overcrowded so don’t repot too

often. Aphid, mealy bug, downy and powdery mildew.

Learning outcomes 7. Understand the care of plants in an interior

situation. 7.1 Describe the environmental factors that must be

taken into account when displaying plants inside domestic buildings.

7.2 Describe the choice of suitable containers and growing media for houseplants.

7.2 Describe the management of one fern (Adiantum raddianum), one foliage (Ficus benjamina) and three seasonal flowering plants (Euphorbia pulcherrima, Kalanchoe blossfeldiana, and Saintpaulia ionantha) under the following headings: potting; feeding; watering; deadheading; re-potting; pest and disease identification and control.

Happy Christmas