R2102 2.3 Describe methods of composting and their use/application

Question 1

What is composting?

Answer 1

‘the rapid aerobic decompostion of organic matter by micro-organisms at elevated temperatures’

Question 2

Conditions for sucessful composting (8)

Answer 2

1. Air - oxygen required for bacteria
2. Water - mositure needed, but not to much. Once moist enough roof cover is useful to keep out excess rain / maintain heat
3. Organic matter mix - balance between green and brown materials
4. Accelerators / activators - help when there is not enough green material - nitrogen fertilisers. Sometimes there is a shortage of brown material.
5. Shredding - increases surface area making more of the material accessible to organisms. Need to maintain aeration and avoid waterlogging.
6. pH - Should not be too acidic. Can add lime to help.
7. Temperature - Rate of decomposition dependant on temperature 55-65c ideally over 70c. Need to kill harmful organisms and weed seeds.
8. Heap size - the bigger the heap the higher the internal temperature. Ideally at least 1m3

Question 3

What is a brown material for compost?

Answer 3

Material containing a high amount of carbon e.g. cardboard

Question 4

What is a green a material for compost?

Answer 4

Material containing a high amount of nitrogen e.g. hay

Question 5

What not to add to a compost heap? (6)

Answer 5

1. Diseased material
2. Weed seeds
3. Perennial seeds
4. Cooked foods
5. Metals, plastics
6. Manure from non-vegetarian animals

Question 6

C:N ratio

Answer 6

1. Everything you out in a compost heap has its own C:N ratio
2. Best C:N ratio is 25-30:1 for producing fertile, sweet smelling compost
3. If C:N ratio too high (excess carbon) decomposition slows down
4. If C:N ratio too low ( excess nitrogen, possibly fresh manures) you will have a smelly slimy heap.

Question 6

C:N ratio

Answer 6

1. Everything you out in a compost heap has its own C:N ratio
2. Best C:N ratio is 25-30:1 for producing fertile, sweet smelling compost
3. If C:N ratio too high (excess carbon) decomposition slows down
4. If C:N ratio too low ( excess nitrogen, possibly fresh manures) you will have a smelly slimy heap.

Question 7

C:N ratio in the compost heap

Answer 7

1. C:N ratio in fertile soil is 10-12:1
2. The ratio in good compost is also 10-12:1
3. Bacteria and fungi work best breaking down material at 25:1
4. General garden rubbish is 30-70:1 - too high in carbon. Therefore add an activator/accelerator to boost nitrogen supply.

Question 8

C:N ratio in the compost heap

Answer 8

1. C:N ratio in fertile soil is 10-12:1
2. The ratio in good compost is also 10-12:1
3. Bacteria and fungi work best breaking down material at 25:1
4. General garden rubbish is 30-70:1 - too high in carbon. Therefore add an activator/accelerator to boost nitrogen supply.

Question 9

Nitrogen rich materials (green)

Answer 9

green leafy material, comfrey leaves, vegetable peelings, grass clippings, annual weeds, young nettles, animal manures, seaweed, feathers

Question 10

Carbon rich materials (brown)

Answer 10

Woody material, sawdust, wood shavings, straw, brassica stumps, bark chippings, newspaper, cardboard

Question 11

Wooden compost containers (5)

Answer 11

1. Make a bunker from bricks, concrete blocks or wood (old railway sleepers ideal)
2. Minimum 1 cubic metre
3. Can be on bare soil (good for organisms) or concrete base (easy to dig out but organisms must be introduced.
4. Need air, water and soil organisms
5. Temp over 70c needed to kill weed seeds and bacteria

Question 12

Wormeries (6)

Answer 12

1. Self contained systems usually the size of a small dustbin
2. Mainly compost kitchen waste
3. Banded and tiger worms feed on the organic matter
4. 10 cm layer of sand is at the base covered by a polythene sheet
5. Bedding material, such as well rotted compost is added for the worms to live in
6. Chopped waste is then added

Question 13

Compost tumblers (4)

Answer 13

1. Containers rotated on an axis
2. Creates compost in a short time
3. Efficient mixing means each batch heats up quickly
4. Nothing to be added until batch is complete

Question 14

Plastic compost bins

Answer 14

Local authorities often provide for free or subsidised. Disadvantage is their size.

Question 15

Hotbin composting (3)

Answer 15

1. Insulated bin that can compost meat scraps
2. Produce compost in a short space of time - 12days at 60c
3. Can be expensive

Question 16

Hotbeds (9)

Answer 16

1. Bulding a loose heap to get plenty of oxgyen in (fresh manure and straw)
2. Invert pile anf fluff after 2-3 days
3. Repeat after 3 days and add water if needed to keep moist
4. After 9-10 days the decomposing organic matter is made into the hotbed at the site where plants are to be grown
5. Material is then forked into a layers and tamped down. Growing medium is then placed on top.
6. In January hotbed can be made in greenhouse, cold frame, pit, outdoors with insultation in the form of wooden sides and covered.
7. Lasts only about 2 mths
8. Manure and growing medium ratio 3:1
9. Do not let temp go above 24c pt plantsd could be scorched

Question 17

Open Trench composting (2)

Answer 17

1. 30cm deep, add 10-15 cm of compostable materials e.g. kitchen scraps, prunings, thinnings etc
2. Simple to do - dont have to aerate, turning heaps
3. Nutrition is right at the root zone
4. Encourages stronger roots, as root burrow down to get to search for the nutrition

Question 18

Trench rotation (3)

Answer 18

1. Divide garden in 3 zones: trench composting zone, pathway zone, and growing zone
2. Shift and rotate zones as needed
3. At the end of 3 years you’ve got compost under every part of your garden bed

Question 19

Trenching between rows

Answer 19

Plant crops as usual. In the space between rows did a compost trench. As material breaks down it will nourish nearby plants.

Question 20

Trench dig and drop

Answer 20

Dig a 30cm hole and drop kitchen waste into it and cover.

Question 21

Trench dig and drop

Answer 21

Dig a 30cm hole and drop kitchen waste into it and cover.

Question 22

Leafmould

Answer 22

Can be made in plastic bags or by making chicken wire enclosure. When broken down make an excellent mulch or compost additive

Question 23

Making compost tea from Comfrey or Nettles

Answer 23

1. Use gloves to collect leaves of these plants
2. Chop up leaves
3. Pack tightly into a container with a lid
4. Keep warm e.g. in Sun, black container absorbs heat
5. Mix daily (aerate) - foaming indicates leaves are decomposing
6. When foaming stops (after about 14 days) draw off liquid
7. Dilute the stock liquid 1:10 with water for use as potassium rich liquid feed

Question 23

Making tea from Comfrey or Nettles

Answer 23

1. Use gloves to collect leaves of these plants
2. Chop up leaves
3. Pack tightly into a container with a lid
4. Keep warm e.g. in Sun, black container absorbs heat
5. Mix daily (aerate) - foaming indicates leaves are decomposing
6. When foaming stops (after about 14 days) draw off liquid
7. Dilute the stock liquid 1:10 with water for use as potassium rich liquid feed
8. Do not use on seedlings it will scorch them

Question 24

Making compost tea (4)

Answer 24

1. Use mature sweet smelling compost. Do not use unpleasant smelling compost.
2. Place compost in water - 10lbs for 10 gallons of water ina 40 gallon barrel. Protect barrel from cold and heat
3. Stir with a stick daily for a minimum of 5 days
4. Strain liquid from compost after 5 days, using cheesecloth or burlap. Use immediately without further dilution