Growing Media

Question 1

Explain considerations when growing plants in containers

Answer 1

Restricted root volume 
Waster retention and supply 
Drainage 
Nutrients 
Stability of compost - crumb structure needs to withstand constant wetting 
Sterile

Question 2

Loam based compost

Answer 2

John innes typically
Sterilised loam = clay and organic matter
Peat and sand added for water holding capacity and drainage respectively
Seed compost
Potting compost
1 - pricking out and potting on
2 - potting on from 1 or potting up houseplants
3 - final potting and mature foliage

Question 3

Loamless compost

Answer 3

Soilless
Lighter cleaner to handle
Cheaper - don’t need sterilising
Until recently used peat now use alternatives.

Question 4

Peat alternatives

Answer 4

Coir (coconut fibre)
Garden compost
Wood based - bark sawdust paper etc
Locally available materials such as straw wool etc

Question 5

Describe multipurpose compost

Answer 5

Formulated for wide variety of uses from seed to larger plants
Most are peat free

Question 6

Seed compost

Answer 6

Finer more closely graded contents

Question 7

Environmental implications of peat use

Answer 7

Destroying British wetlands
Not sustainable as it takes many years to develop.
When dug up releases harmful greenhouse gases

Question 8

What is hydroponics?

Answer 8

The cultivation of plants in nutrient solution without soils

Question 9

Considerations when growing plants in water culture

Answer 9

Oxygen supply
Anchorage and support
Nutrition - skilled knowledge
Costs - initial

Question 10

2 methods of growing plants in water

Answer 10

NFT - nutrient film technique. System of troughs and gullies where nutrient solution is pumped.
Aggregate/substrate culture - similar to above but use of a rooting medium such as rock wool and drip fed from above

Question 11

State TWO limitations of using a garden soil as a growing medium in containers. 4

Answer 11

garden soil is not suitable for use in containers because it may be contaminated with weed seeds/pest and diseases,
have a variable soil texture/structure,
may be prone to compaction or
have excessive/poor drainage,
may have a variable nutrient content and pH level or
be heavy to move

Question 12

b) State the effects of growing acid-loving plants in alkaline soils. 2

Answer 12

stunted growth,
lime induced chlorosis
nutrient availability decreases, e.g. phosphorus, iron, manganese and boron which may result in deficiencies

Question 13

State what is meant by the term ‘garden compost’. 1

Answer 13

breakdown/rotting/decomposition of organic matter as a result of the actions of micro-organisms/bacteria/worms