Mother-Hen-Michele
Crowing
Wow! Awesome post!There is an excellent YouTube video on making sub-irrigated planters. I took that concept of the sub-irrigated raised bed and redesigned it. I resized my project to a 2X4 bed raised up on legs. At the time, I was thinking would it be possible to build an elevated planter for people in wheelchairs, where they would not have to bend over to tend the plants. Also, the sub-irrigated concept was to make the planter more self-sustaining. I am happy to say that my elevated sub-irrigated planters are my best ever planter in terms of low maintenance and overall production harvest.
I built my planter out of wood so it would look nice on our decks. Also, I am fairly handy building wood projects, so it worked for me.
First of all, here is the video you requested....
So, I made my sub-irrigated planter up on legs. I lined the inside bottom up to about 6 inches high with pond liner to make the waterproof reservoir. Then I lined the bottom with these 4 inch perforated drain pipes, capping the ends with weed barrier cloth to keep the potting soil out of the drain pipes.
In order for this concept to work, the drain pipes are 4 inches round, so you have to drill an overflow hole at 3 inches. That gives you a 1 inch air gap barrier between the water reservoir full level and the top of the drain pipes. Without that air gap, your plants would drown. Potting soil is simply spread between the drain pipes and the water wicks up through the soil.
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In a normal summer, with average rainfall, I only have to refill my sub-irrigated planter about once a month. Of course, that will depend on your local weather. I inserted a PVC pipe for refilling the planter with water. It goes all the way to the bottom. Then I just cut off a slice of water pool noodle and used it as a water level indicator. When the water indicator is flush with the top of the PVC fill tube, it's time to refill the planter. Again, for me, that is maybe only once a month.
My 2X4 foot planter with a 3 inch water reservoir in the bottom holds about 15 gallons of water. The plants drink up water as needed. All I do is check the indicator to check on the status. When I refill my planter, I stick a garden hose into the fill tube and let it run until water starts coming out of the overfill hole.
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Here is a picture of my sub-irrigated planter full of bean plants. Because they always have access to water as needed, this 2X4 foot planter produces more beans than I ever got out of my in-ground garden planting 3X or 4X as much space. I'm not a great gardener, but with this system, you can't over water the plants because of the overflow hole. And I don't underwater the plants because I just have to look at the water indicator to see the status of the water reservoir. Nature maintains the correct water soil balance.
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The only downside to this planter is that the drain pipes and pond liner add to the expense of the build. When I built my planters, I spent about $50 for the wood and maybe another $25.00 for the drain pipe and pond liner for each planter. For me, it was worth it.
However, in the spirit of this thread and being more frugal, I would suggest that you could make this same planter out of reclaimed lumber or pallet wood, line the wood with feed bags as discussed, and then a much less expensive liner option like a heavy plastic garbage bag. If you don't want to buy perforated drain pipe, you could fill the bottom 4 inches or so with plastic jugs and such with small holes drilled on all sides in them to fill up with water and drain out as needed for the plants.
If you go with a plastic jug option, just make sure you use a heavier plastic container like the thickness that your liquid laundry detergent comes in. The plastic jug has to be strong enough to support the top ~12 inches of potting soil when wet.
I estimate that I could build this type of sub-irrigated planter with free pallet wood, feed bag and garbage bag liner, reusable plastic jugs, and just a 2 foot section of PVC for less than $10.00 total including all the screws to hold everything together. Compare that to paying about $200.00 for a similar planter you might buy at the big box store.
BONUS IDEA: There is a guy on YouTube named Leon who has many videos on making wicking tubs out of different materials. I will link this next video on how he uses plastic tubs with empty plastic milk cartons for his wicking tubs. The advantage to his system is that you really don't need any wood working skills and you can put together one of his wicking tubs in practically no time.
If you like that concept, he has many, many video on his concept but built with slight variations in the materials. So, check out his channel and I'm sure you would find something that would work for you.
Bottom line, if you are willing to learn the concept, you can build your own sub-irrigated planter or wicking tub for pennies on the dollar compared to buying essentially the same thing at a big box store. FWIW, I know that my elevated sub-irrigated planter is a much better build than the kits I see at our local garden centers.
I've read through it, but I will be re-reading it with a pencil and pad of paper later.
