Hello, all! I'm designing a commercial system in Ghana, and we're wondering what your ratio has been for "weight of plant you harvest and eat" to "waste biomass (roots, extra lettuce leaves, tomato stalks, etc). Our goal is to feed all that waste scrap to worms and chickens to create fish food and organic fertilizer, and we need numbers for this grant proposal? Any advice? What's your experience?
Though some methods of organic or synthetic hydroponics systems (like aeroponics) can produce up to three times the bio mass compared to regular soil planting, I suggest using regular weights for your calculation. If it still works good. If it doesn't work at this rate, I would reevaluate your plan. Plumping numbers to get finance is a good recipe for bankruptcy.
Hi Carey, thanks for your input. However, I'm not asking about vegetable production - I have good numbers on that - I'm asking about your experience with how much waste (roots, outer leaves, inedible stems, spoilage) you get for the amount of food you get out of an aquaponics system.
We're going to turn that "waste" into another healthy, useful product through vermicomposting. I want to know how much we'll have to work with.
I do understand your question. I use the same process myself. What I am saying is that in my experience, different growing methods, growing different plants, produce different amounts of biomass. ie I would get three different results if I grew the same cultivar of strawberry using sand vs DWC vs aeroponics. Then it depends on environmental conditions that year. Farming, though quantifiable, is more an art than a science. The only thing one can really plan for is approximate scale. The type of crop you plant also makes a great impact on how much "waste" is available. Then it needs to be defined. What kind of waste is it; brown, green or black? Waste also depends on who and how you sell to. For example, I sell most of my fresh greens, roots on so might only have a few outer leaves to trim. Tomato plants make great compost but needs to be chopped. Peppers produce a lot of wood in comparison. Selling in in a CSA format allows me to tailor my harvest to coincide with customer pickup so less chance of spoilage compared to selling at an open market being exposed all day. The chance of spoilage in Haiti would be higher than in Seattle.
So what I am trying to say is get your data from local soil farm sources for your calculations if you don't have actual experience growing in that environment. I write proposals all the time and applaud your efforts to help the disadvantaged. I'll try to find time to look up some of my previous numbers but in all honesty all numbers are arbitrary. The real question is: is the scale you work with flexible enough not to throw everything off whack if one thing goes wrong. On a well balanced home garden, I plan for 2- 5% biomatter sell-able with 95- 98% waste (compost-able). What are you planning to grow? How much of what?
Sorry if I seem like a stick in the mud.
Melisse, I see looking through that this is quite an old thread from back in 2012. Any chance of updating us on the progress of the system ? Did it work? Was it commercially viable ? Some info on this would be useful. What fish and crops do/did you grow? Is it still functioning ? If no why not etc. All useful data for us beginners.Thanks in anticipation.