Urban Agriculture A New Adventure

Traditional Agriculture • A big piece of land • Cattle, goats and sheep roaming around • Rolling fields of crops • Tractors and trucks • Big farm house • Lots of staff

Large Capital Investment

• Buy the land • Buy the capital equipment • Buy the live stock • Plant the fields • Wait for the crops/livestock to grow.

Urban Agriculture

• Sounds like a anomaly. • How can you farm in the city? • What livestock is suitable? • Not enough space to farm • Too expensive

Traditional Agriculture

• Usually divided into two major groups • Crops • Livestock Farmers often combine these two different types of farming to make a viable entity.

Urban Agriculture

• Almost by definition Urban Agriculture has to be intensive

• Crops must have high yields and good returns because of limited space.

• Livestock must be “green” and non-polluting

Aquaculture • This is the cultivation of fish • Or fish farming • Wild caught fish seemed to have levelled out

with cultivated fish making up almost 1/3 of all fish produced.

• China being the world leader with 1/3 of all its inland water bodies used for aquaculture

World Aquaculture

Aquaculture

• Why is fish the live stock of choice. • Feed conversion ration for fish is very low. • What is the FCR – the amount of dry feed in kgs required to produce 1 kg at harvest of the live stock • Eg cattle is 25: 1 • Pigs 3.5:1 • Fish < 1.5 :1

HYDROPONICS - “The process of growing plants in sand, gravel, or liquid, with added nutrients but without soil”- Wikipedia

AQUAPONICS – a system of aquaculture in which the waste produced by farmed fish or other aquatic animals supplies nutrients for plants grown hydroponically, which in turn purify the water- Wikipedia

Aquaponics • Can be big or small

• this small system has about 30 litres of water

To very large

HYDROPONICS – has recently achieved some notoriety in North America as being used to grow – weed, grass, Durban poison or marijuana Now its legal in California- !!!

Headlines • Recreational sales of marijuana began in

Colorado on 1 January – BBC News • Colorado collects $2m in marijuana

taxes in January 2014 – BBC News

Aquaponics Home Systems • Need to be stable • Low maintenance • Cheap and easy to run • Produce good results • Locally made

What can you grow ? • Just about anything • space is your biggest constraint • Vegetables • Berries • Fruit • Legumes • Root vegetables

Vegetable information

• Vegetables grow up to 30% faster in aquaponics systems than traditional agriculture.

• The vegetable spacing is usually dependant of the type of plant being grown but 250 mm apart is a good average.

• Companion growing is encouraged

“Virtually everything we have tried in our system has grown really well with leafy greens and herbs being the most successful. This includes beans (runner and bush), butternut, tomato, squash, swiss chard, coriander, rocket (wild and sweet), basil (5 varieties), oregano, mint, lettuce (several summer varieties), watercress, beetroot, papaya, lemon grass, watermelon and cucumber. The quality of the aquaponics crops is fantastic. Never before have I experienced such intensity of flavour and aroma. Crop quality is probably the biggest plus associated with aquaponics plants.”

A quote from Leslie Ter Morshuizen’s monthly newsletter

Vegetable information

• If vegetables are being grown for resale, then grow high value crops like cherry tomatoes should be considered.

Vegetable information • “With a standing fish biomass of 800 odd

kg, feeding at around 10kg per day you have the capacity to support approximately 4000 plants (greens) harvesting around 800 per week.”-Earthan Group

• The ratios on smaller systems are very similar

• Therefore a 12kg system could support 40 plants and harvest 8 per week

What fish will be cultivated?

Tilapia of course

Global Tilapia Cultivation (FOA)

Aquaculture in SA • SA produces – in total 4 000 tons per

annum of aquaculture products • This is made up almost exclusively of

products cultivated for the export and elite niche markets.

• These products are – abalone, oysters, mussels, seaweed and trout

• Nothing for the man in the street !!

Aquaponics Home Systems • Need to be stable • Low maintenance • Cheap and easy to run • Produce good results • Locally made

Flow Bin Aquaponics

Aquaponics Flow bins or IBT Systems • Cut in the correct sizes – 600 litres of water

available • Using a lower generally accepted stocking

densities -20kg/m³ • Together with 600 litres of grow media. • A 1200 to 1500 litre/h pump cycles the

water fast enough

Aquaponics Flow bins or IBT Systems -continued • the grow bed acts as a filter • Rudimentary venturi’s on the return water

provide aeration or/ small air pumps • All the fittings can be obtained from

hardware store and /or Pet store • Grow media can be locally purchased or

bought from nurseries

AQUAPONICS Costs of the flow bin system- continued

• Total cost < R2 000

Urban Agriculture • Is a very large topic

–Rural /peri-urban agriculture – sustainable living – food security

–Urban live stock options –Urban rooftop

agriculture/aquaponics –Urban vegetable gardens

Aquaponics • Aquaponics is not limited to home systems. • Extremely large commercial systems are in

place in country's like Israel, USA, and Australia.

• Commercial systems are typically of the order of 4 000m² of grow beds with fish volumes to match

Aquaponics • Commercials systems are often various

combinations of the four major types of grow beds dependant of the crops to be grown. – Nutrient film technology “NTF” – Deep water culture or “DWC” – Media (stone chips, LECA®, coyer mix

vermiculite, polystyrene, etc) – Wicked beds – media, geo-fabric membrane,

soil

Wicked Bed

Aquaponics • Different types of grow beds work better

with different crops. • Some crops are heavy feeders requiring

higher fish concentrations. • Supplementary feeding of worms improve

crop performances

Where to from here

• We have the makings of a fabulous facility. • Refurbished labs and accommodation on

site • We need assistance from the City,

academia, grant and donor funding. • There are endless research possibilities

around agriculture and aquaculture.

The start has been made • We need to insure that the good work that

has been done is continued.

• I believe in this program and I hope you will too.

Thank you for your time.