Post by shinester on May 13, 2015 15:28:43 GMT 10
I've got some lettuce in, well in volcanic rock, no pumps hydroponic. The aim behind this is to work towards a very low maintenance prepper garden, which is part of a bigger long term self sufficiency plan.
Thinking with prepping/self sufficiency [at least my version of it] in mind it's clear that water, electricity, space, labor, material availability/costs and fertilizer might be in short supply.
Water
The problem with putting plants into the ground is you loose a lot of water through drainage and evaporation. From online data and from my own experience these kind of hydroponic set ups use hardly any water at all, less than 5% of your typical garden. With my phase 1 experiment, even though the containers were fairly small I hardly topped it up with water. If anything the problem [at this time of year] is that it catches too much water so I have a simple hole to allow run off to keep the levels below the root ball. This is important as the roots will rot if they're all in the water. Obviously your plants have to be planted in the rock to a depth where some of their roots touch the nutrients in the beginning to get them going.
Whilst rain will dilute the nutrient solution, I'm confident that it won't have a big enough impact to matter in the 3 months of a growing season, though if it does, it's an easy fix with topping up the nutrients.
Electricity
Most hydroponic systems use pumps that need electricity that could be put to much better use. Obviously with a no pump system we've skipped the need for solar etc. cutting costs and problems with pumps. The downside is 'I suspect' that yields might not be as high, though I've no proof either way on this.
Space
Most backyards are small and to grow enough for a family is a massive challenge. There's certainly some people out there who do this on a 1/4 acre block, though it's a challenge to get the soil right, to get the sun right and so on. Also people only think about growing plants in the ground, but plants will grown anywhere there's sun, what about shallow slanting roofs like the garage? Obviously it would be a pain to get up there every day to water so it would only work if it were very low maintenance. Whilst I have no current plans to climb the roof, and I haven't nearly filled the backyard there's lots of extra space up there if things needed it. Hydroponics give better yields per square meter, so it uses the space you have and can find better.
Labor
Whilst the setting up of such tubs takes some effort, I went literally 2 weeks in summer without touching the plants on the first experiment. This time with larger tubs [and water capacity] I would doubt I will need to look in on them more than a couple of ours weekly and just to check for pests, disease and nutrient deficiency. It's likely to be less, I generally check in on them more than I need to. There'll be little and probably no weeds as the weeds as plants have to have established roots to dip into the system. Growing seedlings fairly normally and planting in when they're roots are big enough being necessary. Soil based pests probably also zero. Hopefully snails don't like volcanic rock.
Material availability/costs
To set this up, you need a opaque container to stop algae growth and something to hold the plant. If your plant needs to support itself standing up then it needs something like rock to allow it's roots to give it stability. I used volcanic rock as it's been used for hydroponics from the beginning, it holds water and it gives the roots better purchase to hold onto. We don't really need the water absorption capabilities as the tips of the roots will sit in water all of the time so the plant will have more than enough water. You could probably use sand or dirt too. Low lying plants such as lettuce could be grown on a piece of foam/board/anything to hold it up in the air a little so the roots dangle into the medium.
I use a piece of PVC inserted into the rock as a way of checking the nutrient levels. The tubs I got were pretty cheap at $3 each, though anything that holds water would do the trick.
Fertilizer
I've used commercially available hydroponic mix as a starting point. The costing is at a premium compared to making your own from chemicals. See HERE.
As well as storing up a decent supply of nutrients, a couple of hundred dollars is probably a 5 year supply, it's cost hardly anything and remember we don't use much water so we don't use a lot of nutrients either and there's no run off and waste. When we do harvest we can re-use these nutrients on any plants we have in the ground.
It's worth looking at alternatives that we self generate such as composting teas [thanks VegHead] and pee-ponics which has been used for eons in gardens. Adding wood-ash for the Potassium is generally a good plan as they might be a little low and whilst a great for self sufficiency, their constitution varies and so will not give predictable results, which isn't ideal for this stage, though I'll certainly run some comparisons when I plant my next set.
Conclusion
Growing with a no-pump hydroponics set up allows the low use of water, low labor, higher initial costings but very little ongoing, high yield per plant and great use of space.
Thinking with prepping/self sufficiency [at least my version of it] in mind it's clear that water, electricity, space, labor, material availability/costs and fertilizer might be in short supply.
Water
The problem with putting plants into the ground is you loose a lot of water through drainage and evaporation. From online data and from my own experience these kind of hydroponic set ups use hardly any water at all, less than 5% of your typical garden. With my phase 1 experiment, even though the containers were fairly small I hardly topped it up with water. If anything the problem [at this time of year] is that it catches too much water so I have a simple hole to allow run off to keep the levels below the root ball. This is important as the roots will rot if they're all in the water. Obviously your plants have to be planted in the rock to a depth where some of their roots touch the nutrients in the beginning to get them going.
Whilst rain will dilute the nutrient solution, I'm confident that it won't have a big enough impact to matter in the 3 months of a growing season, though if it does, it's an easy fix with topping up the nutrients.
Electricity
Most hydroponic systems use pumps that need electricity that could be put to much better use. Obviously with a no pump system we've skipped the need for solar etc. cutting costs and problems with pumps. The downside is 'I suspect' that yields might not be as high, though I've no proof either way on this.
Space
Most backyards are small and to grow enough for a family is a massive challenge. There's certainly some people out there who do this on a 1/4 acre block, though it's a challenge to get the soil right, to get the sun right and so on. Also people only think about growing plants in the ground, but plants will grown anywhere there's sun, what about shallow slanting roofs like the garage? Obviously it would be a pain to get up there every day to water so it would only work if it were very low maintenance. Whilst I have no current plans to climb the roof, and I haven't nearly filled the backyard there's lots of extra space up there if things needed it. Hydroponics give better yields per square meter, so it uses the space you have and can find better.
Labor
Whilst the setting up of such tubs takes some effort, I went literally 2 weeks in summer without touching the plants on the first experiment. This time with larger tubs [and water capacity] I would doubt I will need to look in on them more than a couple of ours weekly and just to check for pests, disease and nutrient deficiency. It's likely to be less, I generally check in on them more than I need to. There'll be little and probably no weeds as the weeds as plants have to have established roots to dip into the system. Growing seedlings fairly normally and planting in when they're roots are big enough being necessary. Soil based pests probably also zero. Hopefully snails don't like volcanic rock.
Material availability/costs
To set this up, you need a opaque container to stop algae growth and something to hold the plant. If your plant needs to support itself standing up then it needs something like rock to allow it's roots to give it stability. I used volcanic rock as it's been used for hydroponics from the beginning, it holds water and it gives the roots better purchase to hold onto. We don't really need the water absorption capabilities as the tips of the roots will sit in water all of the time so the plant will have more than enough water. You could probably use sand or dirt too. Low lying plants such as lettuce could be grown on a piece of foam/board/anything to hold it up in the air a little so the roots dangle into the medium.
I use a piece of PVC inserted into the rock as a way of checking the nutrient levels. The tubs I got were pretty cheap at $3 each, though anything that holds water would do the trick.
Fertilizer
I've used commercially available hydroponic mix as a starting point. The costing is at a premium compared to making your own from chemicals. See HERE.
As well as storing up a decent supply of nutrients, a couple of hundred dollars is probably a 5 year supply, it's cost hardly anything and remember we don't use much water so we don't use a lot of nutrients either and there's no run off and waste. When we do harvest we can re-use these nutrients on any plants we have in the ground.
It's worth looking at alternatives that we self generate such as composting teas [thanks VegHead] and pee-ponics which has been used for eons in gardens. Adding wood-ash for the Potassium is generally a good plan as they might be a little low and whilst a great for self sufficiency, their constitution varies and so will not give predictable results, which isn't ideal for this stage, though I'll certainly run some comparisons when I plant my next set.
Conclusion
Growing with a no-pump hydroponics set up allows the low use of water, low labor, higher initial costings but very little ongoing, high yield per plant and great use of space.
