by jrc+
Concerns about hydroponics
December 18, 2009 in Getting Started, Materials and Resources, Seeking Advice by jrc+
Hi all,
I love the idea of urban farming. I have previously owned an AeroGarden but I am looking forward to going DIY. I am just in the research phase of getting started, and I have some questions/concerns about hydroponics.
I would very much like to proceed as “low-energy” and using as many “low-impact or recycled local materials” as possible. This is what appeals to me most about the windowfarming concept. However, most of the hydroponics solutions I’ve read about do not fit those qualifications. Most low-cost pumps are presumably manufactured somewhere far like China. I’m also against running a pump continuously, and even a simple timer requires electricity (and is also probably imported from somewhere).
In my googling, I’ve come across a few approaches that are pump-less:
- http://www.csupomona.edu/~jskoga/dripirrigation/
- http://www.flickr.com/photos/c4g/3062627532/
- http://www.instructables.com/id/Solar_Thermally_Pumped_Hydroponic_System/
- http://www.instructables.com/id/Solar-Powered-Vertical-Drip-Hydroponics-with-Frenc/
Even so, the drip irrigation approach uses PVC tubing, which I don’t have and can’t make myself, and the ebb-and-flow approach uses materials such as perlite and rockwool, which I’d have to go out and buy. More importantly, such materials are seriously not low-impact if you look up where they come from.
I’m not against buying materials if those things are really necessary, but each purchase seems to go against the low-impact intent! I might as well buy another AeroGarden.
So as a newbie, I’m questioning why hydroponics is really necessary for a successful windowfarm. Could one not just use a little potting soil instead? And how well do perlite, clay pellets, etc. match up against more easily findable “urban” materials (sand, gravel, glass, styrofoam, sawdust, …)? Are there others out there who are thinking along similar lines and have tried any alternative techniques or materials?
/John
Stockholm, Sweden
It is possible to go low impact, I am a teacher biotechnology and my class is starting a project build of 100 % recycled materials. They are aming at no-impact.
- you can us sand, grid , old insulation materials or glass as substrate for your plants, depending on which plant you are cultivating
- do not use potting soil (big impact)
- look around you don’t have to purchase anything to build the installation
- no pump: we use a two containers system which drips the nutritionsolution into the system. the full upper container drips, the lower empty container collects the effluent. after 12 hours we switch the containers manual
- biggest problem is to produce a good and stable nutritionsolution
Bert
Belgium
I have the same concerns. I don’t understand hydroponics very well so I don’t know the advantages. So let’s just put that aside for the moment.
In terms of growing shallow rooted plants , e.g, small greens, green beans etc.
I think that it might be possible to use a light growing medium in a smallish container. I use a fine peat mixture enhanced with manure to grow my seedlings indoors. (I do not use vermiculite, or pearlite or any of that stuff–not necessary and not good for you).
The seedlings grow pretty big in a very tiny container, so if we increased the container to a soda bottle size—we should be able to grow a tatsoi, cress, container green beans, peas, certainly basil and other small herbs.
On the other hand—maybe it would make more sense to take up the space and grow some substantially sized food, e.g., tomatoes in a hanging bag—people do this on their patios—why wouldn’t it work in a window? Indeterminate, smallish tomatoes—like a cherry tomato might work.
The things that seem to make my seedlings successful are the following:
-capillary mat to water them from below (no electricity needed, I add water to the resevoir once a week. So if we could incorporate some kind of capillary system, that might work.
-water from my gold fish tank (no kidding—this stuff works and its free)—but you could buy some locally provided organic-water soluble fertilizer, e.g., seaweed, compost tea etc.
Can anyone else comment on why using soil wouldn’t work in this context?
I ran my small exploratory system using as many recycled components as I could (kitty-litter buckets, odd bits of PVC pipe I scavenged, etc). For media I used a mix of hydroton clay pellets and coconut fibers.
I’m making my second tweaking system using a solar fountain pump (very low rise, but I can use shadows to make the system cycle off-on).
I’d like to investigate more “home grown” media and passive power as well.
I have similar concerns. Although I enjoy traditional vegetable gardening, I am new to hydroponics, and have questions about the expenditures involved. I grow my own food in the warm months in part because the money that I save on groceries can stretch all year long (once you factor in canning, pickling and drying). I would love to have fresh home grown veggies in the dead of winter, but not if it is going to cost me more to set up and run my garden than it would to just go to my local grocery store and buy them. Can anyone speak to the increase in the electricity bill? or the actual cost of the pump, PVP pipes, etc.?
I am excited by the possibilities here, but just need some indication that we will at least break even by trying this.
I’m working on designing a system that uses a modified bicycle pump:
http://www.instructables.com/id/make-a-manual-vacuum-pump-for-under-%2420-by-convert/
Buy a pump from craigslist or use a friend’s old one. It may have been manufactured in China, but you’re essentially recycling it, in that it’s being re-purposed. Though the problem with this approach seems to be timing; that is, how to provide a steady drip to your farm. Won’t my plants go hungry while I sleep? I’d like Britta to chime in with a solution.
As for the PVC, listen to offlogic: the stuff exists in such abundance that it shouldn’t be hard to find scraps. Is there a site near you that sells recycle construction goods?
Good luck.
although i enjoy the concept of the window farm… i am extremely into low tech low impact and grow most things inside using the wick method… which is cheap and carefree.
In wick hydroponic systems, plants control watering rates. Quite simply, the lower end of a highly-absorbent wick is placed in a reservoir containing nutrient-enriched water. The other is embedded in the growing medium close to the plant roots. As the plants need more water (and the nutrients it contains), it is drawn up the wick and into the water-retentive grow media by capillary action. As the plants absorb the solution at one end, more is pulled into the wick at the other…. as a growing medium i usually use sand or gravel.. it’s all very cheap as the only thing i ever buy are the actual seeds. i re-use all sorts of containers from butter dishes to yogurt containers… it’s very simple and many plants can feed off the same water source.
EmailRonda: Sorry to go off on a tangent. I attempt to use the wick method for my potted plants while I’m on vacation. I return to find my plants swimming in water. Have I purchased the wrong type of string (it’s not specifically wick string), or do I have the water source too high above the height of the plant? Any advice would help. Thanks.
Why couldn’t a pump be done like an Artesian well? The water would drip into one larger container connected to a smaller container below it with a line running back up to a reservoir above all the plants? The gravity from the water in the larger tank flowing into the smaller tank would create the pressure to push the water back to the top. Am I missing something?
Also, I’d like to grow plants in groups. But, I only see plants being grown isolated here. Can I use a long narrow container, like a thin, shallow window planter, and grow in groups?
Why couldn’t wicks be used for a window farm for a passive system?
I found the suggestions in the comments section helpful, especially about wicks and about a gravity feed system that is changed by hand.
The Wikipedia article on hydroponics suggests polystyrene packing peanuts as a growing medium. I have not tried this.
Wikipedia also suggests a “Mariotte’s bottle” for providing constant drip flow:
http://en.wikipedia.org/wiki/Mariotte%27s_bottle
OK, some really stupid questions here. I am new to EVERY aspect of this… growing plants, hydroponics, anything mechanical… you name it. Still, some of these systems look simple enough for even me to try, maybe with my husband’s help if I can get him to play along.
I have some concerns about growing plants hydroponically that are intended to be eaten (as opposed to ornamentals). How could hydroponic solution possibly contain all the micronutrients (trace metals, etc.) that are needed for truly healthful, nutritious plants? Also (although maybe this is better posted on another forum) what about the potential health effects of eating plants that are contained in plastic being baked in sunlight that is repeatedly having water passed over it, possibly leaching out harmful chemicals? Isn’t that why we’re not supposed to reuse plastic water bottles now and switch to the metal ones?
Don’t get me wrong, I love this idea and really want a way to make it work. I’ve fantasized about window gardening a long time but I keep getting hung up on what is the safest material in which to grow a plant I’m intending to eat. I’m pregnant and just read “Healthy Child Healthy World” about environmental exposures so maybe I’m kind of hypersensitive about all this stuff right now.
THX!!!