Good question... it seems like I'm pushing that boundary every year. More than anything I fertilize the shit out of everything and kind of don't worry about watering.
The area of my planter is 12'x4'. Everything I read said the limit for capillary action to work in the bed is about 11 inches, so my reservoir is about 10 inches deep and the soil is another 10 or so. A 4" pipe holds a little over a half gallon per foot and I have over 65' in mine, so between the pipe and the space between the gravel, it easily holds over 40 gallons.
Wow. That is incredibly water efficient. With as expensive as water is here I'd easily recoup the cost in a season or two.
Solid progress over the past few weeks. Very happy overall. 4 of the cucumber plants didn't survive, but 4 new ones from seeds are starting to really sprout now. Hidden in there are some big eggplant fruit, and some peppers will be ready to harvest next week. Tomatoes are doing well, lots of new flowers, no fruit showing yet.
The reservoir holds water. That area becomes high humidity. The water gets "filled" with gravel, and then the landscapers fabric goes on over top, and then the topsoil gets put over the top of the landscape fabric. Importantly, a "runoff" or "overflow" hole is cut in the side so that the water level will never get to be higher than the top of the gravel. This is important, because that means that the fabric will never get wet, and the soil will never get wet. With all the air space in gravel, though, that becomes very high humidity. Much higher than the soil above it. So what happens is that the very top surface of the soil gets dried out, but the very bottom of the soil is beside a ton of humidity. This "osmotic action" pulls the humidity out of the air below the topsoil, and up into the soil itself. That means that there is moisture in the soil, but it's never wet. As long as there is water in the reservoir below it, that will put moisture in the air in the gravel layer, and there will be moisture for the soil to pull up into itself. To fill the reservoir, there is a standpipe at one end that you just dump a hose into. That pipe goes all the way down to the water level, and allows you to fill up the reservoir until water comes out the overflow, which means it's full. This is a good pic of that: On the far end, the orange cap is of the fill pipe, and the white square is a piece of old cutting board that I used to frame the overflow drain. (It's just something that I could glue easily to the membrane to keep everything water tight). You'll see a sock-covered drainage pipe snaking in the reservoir, and that's connected to the end of the filler pipe. When this gets filled with gravel, this just lets the water go all over the bottom of the reservoir easier than if it had to make it's way through all the gravel because everything will be full of gravel, but the sock and pipe, which is perforated, will leave lots of space for the water to fill up and will soak into the gravel evenly throughout the bottom of the box. Might not be necessary, but it was suggested in some research I did so figured "why not". Then the box gets filled with gravel. You can see that the water level only goes as high as the drain on the far end... and that is by design. Once the gravel is above the drain, you can then put down your fabric and your soil. As @AFHokie says, the osmotic/capillary action of the water is only 11" or so... what that means is that from the base of your topsoil, measuring up, only 11" or so will get moisture from the humidity below. Not the actual water, but the humid air above the water, around all the gravel. Anything above that will stay dried out. The reservoir can be as deep/shallow as you want, it's where the soil/humidity barrier starts that you measure your 11". It was a bit of work, for sure, but I think the gardens are doing great, and I have to think that the wicking nature of the beds helps keep things constantly watered, even during the hottest of heat waves (like I'm experiencing now).
Nett is right, you only have to water your peppers every 2-3 days. Stick your finger about 2" deep in the soil and if it is wet you don't have to water it. Peppers don't like a bunch of water, they will stop growing and drop their leaves if you water them too much.
Are you asking her if she can suck a golf ball thru a garden hose? Because I think that might should be in DM.
Here's some links I used for my research before I built my bed: https://permies.com/t/21756/Improved-wicking-bed https://www.urbanfarm.org/2019/08/13/wickingbeds3-0/ https://www.permablitz.net/articles/thoughts-wicking-beds/ https://www.postbulletin.com/life/l...cle_5b112160-3860-53e9-bd2b-76bf8658f190.html https://deepgreenpermaculture.com/2...-best-rocks-to-use-for-building-wicking-beds/ And my watering assistant:
yeah I'm starting to figure that out. Unfortunately I have my cucumbers in the same bed as the peppers so I just went the Nett route and have started fertilizing the shit outta them. Next time I'll plant the peppers in their own bed so I can water them by hand every few days, but with the soaker hose right now I'm at 15 minutes twice a day and they seem to be responding well.
What a cute assistant. Looks like you have yours hooked up to the hose. I'm growing my own now, but mine only responds to milk.
@Nettdata , do you grow jalapenos? Do you find them to be reasonably spicy? Same question for anyone else in a cooler climate... @walt ? From what I've read, hotter and dryer conditions result in hotter peppers. The jalapenos I grew back in Bama would melt your face off. Hot as shit. My niece was insistent on eating one from the garden once (seeds and all, she ate it in a blink before I could stop her) and it made her throw up repeatedly, develop a fever, and be so sick she missed school the next day. The jalapenos growing here are the same variety, early jalapenos, and they have nearly zero heat. Like, white pepper is probably hotter than these jalapenos. I may actually have to grow hot peppers now. I have some seeds for habs and ghost peppers I could try next season.