Balcony garden has been doing well and is getting new additions. When Covid is past I’ll be looking at travel again, so time to look at automatic watering.
I’ve based my plan around the type of drip feeding system that uses collected rainwater. However, in this case I’ll be feeding the system by filling a 50gal Ag tank (similar to our metal shop’s water buffalo) once every so often from utility. It’s being done this way since I have to run the hose from my utility room which is not wise to leave unattended.
I know rain barrel systems already exist for gravity feed, but they really need a minimum of 15 feet ideally 30 from what I’ve read.
So I’m investigating options:
gravity systems anyway and I can get it about 10 feet, but will have uneven pressure
use a nitrogen cylinder and regulator to provide some pressure to the system (like 10 PSI of boost should be plenty across 6 square feet)
build a timer for a typical transfer pump to feed a normal drip system; would need a pump that can operate at lower GPH or not burn out when restricted.
Now the last option is likely the easiest, but also I’d like to investigate the gravity options if people can provide practical insight. Why? One, I think it’s neat; two, I’d like the watering process to draw less energy; three, just like to make things
Cheers,
-Jim
Edit: apparently I was swapping GPH and GPM in some of my math which makes me lean more towards the simplistic route.
I’m thinking if I go that route just get one of these 12v ATV sprayer tanks (which have about 1 GPM capable flow), and setting up a solar panel and timer. https://www.amazon.com/dp/B00HO3IWII/ref=cm_sw_r_other_apa_i_K8W1Eb5M89N3W
12 feet would give you 5.196 psig if the the bottom of the tank were at 12 ft. Each 2.31 ft would give you another 1 psi. I think that might be enough for you.
Forgot to add some items, and realized I had a typo in the height which is 10’ not 12’.
10’ is what I can fit to the top of the tank (bottom would be about 8’ for a typical ag tank, 9’ if I can do a lower profile, RV storage tank or similar)
The tank will need to make about 30-40 feet of linear run between the plants. I can do the trunk of the line higher and add drops going down to minimize water having to climb from plumbing done ground-to-planter
Then it would need to be filled up there too in practice unless I run about 75’ of hose horizontally, followed by a 20’ vertical climb to the tank for filling… from a washing machine tap.
Of course that’s all assuming they’d even be on board
Yeah rainwater can’t be reasonably collected here unless I convinced my apartment to re-route their gutters to my balcony.
I get away with so much here, but that’s gonna be a pass from them I’m sure.
Well it would be something to control power to the pump. Whether that be an old-school outdoor mechanical timer, or a smart thing, remains to be seen. I’d probably go simpler to start for that style of setup, and once everything is dialed-in with respect to flow out each section add some moisture sensors and have it respond based on those.
If you go for a moisture sensor, go for the capacitance types as opposed to resistance types. I’ve watched a lot of this guy’s videos, and he had one on moisture sensors:
I’m looking to do something similar, and not to hijack thread, but do you think for the pump at short distance a peristaltic pump would work? I was thinking have 6 pumps going to different plants that way It’ll be easy to know how much h20 is going where! Let me know your thoughts
You can also extend the use of these sensors by only powering them for a very short period of time while actively reading them. For soil sensing, checking once an hour or so would likely be fine. Even checking for 1 sec per minute would extend the life of the sensor by a factor of 60.
Yeah, someone mentioned that in the comments (and I can see how that slows the electrolytic effect), but then it devolved into soil pH talk among other things. Seems like keeping the metal insulated might be a good idea, but I don’t have any practical experience here yet.
I decided to just go the sprayer tank route. Apparently this thing has an automatic pump shutoff on top of the bypass when the pressure builds like a pressure washer; for the cost of the whole system I was surprised.
I setup some fittings to convert the Boom spray output to a garden hose outlet (which will feed the drip system). This leaves the sprayer available so I can do manual watering and filling etc since there is a cutoff valve for the boom output.
I’ve got the supplies for the drips and mini sprinklers, and now it’s time to do all of that. I bet I’ll go through a whole tank just tweaking everything
I’ll post an update when the rest of the drip setup is operational
There was a recently featured Instructable showing an herb growing station with moisture sensors, LED lights, a touchscreen, and an Arduino. It did not actually water the plants, but it did show when the soil was dry.
I have an interest because I picked up some Seeed Studio TFT screens before Tanners closed and this looked like a fun project. My sensors arrived earlier this week. (I bought the cheaper resistive version - not the capacitive style).
The system is plumbed and functional, though I’m still dialing in the amount of watering for the various nozzles. Next up will be adding moisture sensing and automatic timing.
This ended working wildly well. Harvested grapes*, herbs, peppers, strawberries, and more on my balcony.
Well the seasons are changing and now I wonder if I need an improvement.
I know some plants I was looking to add into the mix such as rosemary would handle winter better than others, but one consideration for the system is it currently will not handle freezing temps. Given that it’s not typically sustained below freezing our winters of late I could potentially get away with insulating the lines, but given I’m on the 3rd floor balcony this likely won’t end well
I’ve thought about adding some heating elements to the mix but I have to wonder how efficient it can be. During the winter enough plants may not do well enough I might switch to hand watering.
In addition to this consideration come winter, I’ve also been mulling a switch to hard piping the core of the plumbing. I can make it quite a bit cleaner and more durable that way.
One thought I had was to switch to many small rain style sprayers over the current nozzles. Given that it’s basically an open hole at every Tee I wouldn’t worry about the plumbing freezing as much, only the tanks. The tanks are large enough I could not fill them to above 70% volume and add a temp sensor to disable the pump when temps are in a danger zone.
Heating the tank I suspect would be easier than the lines of I did so.
All in all even if I go to hand watering in the winter in gonna start installing the hardline for cleanliness; if I did attempt a heating mechanism it’s the best time for it.
-Jim
You probably read that right. Yes, I’ve managed to harvest grapes in Texas, on an apartment Balcony on the 3rd floor
Edit: oh, known problems / lessons learned:
Algae growth. It’s not crazy, but it’s ever present. System is filled from city water. Haven’t put any additives in it.
I need to source optimal tank sizes. Right now 35gal Ag tanks are OK, but likely not the most cost efficient Rain barrels are nice and cheap but open sold without a closable to so I’d have to make them. Might be a worthwhile trade-off and not as critical since I can band a tarp or something. Limiting factor in tank selection is width of doors to get it up without a crane, and if there’s a flat side for a better bulkhead or if the one it has makes enough room for better fittings
I could probably switch to a more energy efficient pump or drive it differently. The regulator is controlling like pressure for the current drop system, but the pump idles at speed anyway. This is a larger battery killer
I’m gonna add a lot more planters and spread this out. I meant too after the original proof of concept but the grape vines grew over the railing faster than expected. They need more dirt so it’s more efficient on water usage, or I need to move them to a second zone so when I water them more often I don’t waste water on the others.
