So here's what I've been thinking of trying next year. I'm a landscaper and I have very good access to 15 and 20 gal pots. So what if I took a 20 gal pot and turned it into a kind of self watering pot, but instead of having the water in a larger (expensive) solid pot, I drop in a smaller solid pot where the roots could grow down to it. Let me know if you think this would work or not. :-)

I haven't used a SWP yet, but I've read up on them plenty. It seems to me that unless your galvanized mesh screen is very fine, you will have trouble keeping the growing medium and the water reservoir separate and you'll eventually have much less room in the reservoir for water as that space collects medium and, perhaps, roots. Too, as the tree becomes rootbound, separating the reservoir from the unpotted tree could prove very difficult - better cut off any lip on the reservoir bucket. It's an interesting idea, though.

How do you plan to wick the water from the reservoir to the growing medium?

Why not just use half barrels for the pots?  30 true gallon pot and $5 each, hard to beat.  

Where would you find a 30 gal pot for $5? Yes some media would mingle but the pot would need to get root pruned every few years so at that point you would cut above the mesh completely separating it and throw away the mesh and soil to be replaced with new. I get what you are saying about removing the lip from the inner bucket. Good point.

Aaron,

55 gallon plastic barrels, $10 each.  They are actually 60 gallons with the head space. That is true gallons not the nursery pot idea of gallons.  You cut them in half and you have 2 30 gallon pots that will last a decade even in the Florida sun.  That is what I am using for my SWP experiment.

AD, keep in mind that Mr. Florida, Wills, doesn't have to move his 2 million pound SWPs, or if he does, I'm pretty sure he has a giant crane to do the heavy lifting. Better have a strong back or some large children come winter...and then spring. Heaven forbid you have to do the fig shuffle like I do.

I'm moving to Florida.

Aaron,

The plastic drums are available on craigslist, get ones that held food or a mild chemical.  The ones I use had detergent in them originally.  

Neil,

I forgot all about your shuffle...easy to do as it is 78 degrees at the moment.  Moving them could be an issue.  For the record I do not have a crane but do have a diesel tractor with a front end loader.  

how does the water absorb into the soil? in the picture, it looks like the soil would stay dry and the water would stay in the bucket.  There's got to be some water getting to some soil for the wicking action.  I don't think just having the roots grow down into the water is a good idea.

You could line the nursery pot with heavy mill plastic, flip the solid bucket over and drill a bunch of holes in the sides of it.  I'd use  bucket that's just a bit smaller in diameter than the outer pot.  You don't need much wicking soil.  If the bucket is too tall, you can shorten it.  Don't need the galvenized mesh.

Basically, what I'm describing is a giant version of FMD's mini sip.

Hey Mr. Florida.........;) would you even need to move a 30 gallon pot in our zone? Other than a really hard freeze which rarely happens I wouldn't think you would need too?

I doubt your diesel tractor would get all of my 150 pots into my 10x12' greenhouse if they were in 30 gal tubs, but anyway... I did search Craigslist and the food grade drums are $20 around here. Actually cheaper than I thought they would be. However, I do need to keep them smaller because of the shuffle. 20 gal is good enough for me. FYI: Your pots weigh approx 750lbs and will use a 1/2 yard of soil each. I spend approx $7.50 on my soil and amendments for every 3 gal pot. Just a mere $225 per 30 gal each.

Because you are watering down the PVC pipe and stopping the water when you see water coming out of the bottom drain holes, the soil around the top of the bucket would always be wet. Roots would then gravitate to that area, and then reach down into the bucket. At least that was my theory. On second thought, you could press down on the mesh letting it dip down into the water a couple inches. Problem solved.

Blueboy,

I would not move them for cold just flood.  I am putting them along the back fence next to the lake so the only time I would have to move them is if the lake flooded.  It has only done so once in the 10 years we have been here after two hurricanes a week or so apart.  

Aaron,

I think your math is off.  A cubic yard would be 27 cubic feet...so half a yard would be 13.5 CF.   The pots WITHOUT the reservoir only hold like 3 cubic feet.  #With a reservoir like 2 cf?  

[QUOTE=ADelmanto]Because you are watering down the PVC pipe and stopping the water when you see water coming out of the bottom drain holes, the soil around the top of the bucket would always be wet. Roots would then gravitate to that area, and then reach down into the bucket. At least that was my theory. On second thought, you could press down on the mesh letting it dip down into the water a couple inches. Problem solved. [/QUOTE]

but as the water level drops, the water is below the surface of the soil, so no more wicking action.  So the size of the reservoir is wasted.  You'd have to keep the reservoir full for any soil to get wet, which kind of defeats the purpose of having a reservoir.  The bottom of the wick should be near the bottom of the reservoir. no?

I agree with James, I'm no SWC expert, but I don't understand how this is going to work.

Ooops looks like I multiplied one of my numbers twice. Sorry. Lol. More like 6.5 cubic feet. What if I dropped a section of 4" perf drain pipe filled to the top with soil in the center of the reservoir as the wick? The screen would rest on top; again slightly depressed. That should work.

That might work. It should wick up and spread out.

Design # 2. No mesh

The key, for me, is to spend little to no money on the pot itself. I have access to nursery pots, gal pails, and scraps of PVC pipe.
http://figs4funforum.websitetoolbox.com/file?id=1729858

take a look at bill's SWP link. you basically make space in the bottom using large pvc pipes and some sort of mesh. don't need two container to make SWP.

the sketch in post #17 is lacking an overflow, how would one know when inner container holding water is full?

In response to the last 2 posts, the problem with Bill's setup (for me) is the large (20 gal) pot with no holes. I don't have those. All of my pots have holes. I don't need an overflow because all extra water drains out the bottom of the larger outer pot. In fact that would be how I would know I watered enough. This is all in theory mind you. I'll have to try some out in the spring.

you can always plug those holes.. 

Pete, are you trying to be difficult? Just kidding Pete. LOL I actually appreciate the feedback. I'm one of 8 kids. We argue about everything. It helps the process. Yes, I could plug the holes. I build ponds. I have the material. I'm thinking of another, easier, way. Like rooting cuttings there are many ways to achieve the same goal. Maybe this works. Maybe not.

[QUOTE=ADelmanto]LOL I actually appreciate the feedback.[/QUOTE]

Here's some more ;)

Without the mesh, what's keeping the medium from falling into the reservoir around the smaller inner wicking pot?

Also, when filling the reservoir, you said you expect to see the water come out the holes of the larger nursery pot?  For that to happen, the middle reservoir pot would need to overflow and drain down through the medium around it, drenching all that medium, which partly defeats the concept of SWP.  That drenched medium will also wick up and keep everything too wet (in my opinion).  The basic concept of SWP/SIP is that the meduim only sucks up what it can handle, the only part that is "drenched" is the small wick.

You said you have plenty of scrap PVC, put a hole near the top of the reservoir and a hole in the side of the big nursery pot at the same height, so you have a horizontal (or [u]very[/u] slightly downward) overflow path.  So you'll know when the reservoir is full w/o overflowing it.

It's looking good!  Keep at it.  It may be more work and complicated than some, but cheap is always good in my book.

 

It is next to impossible to plug all those holes effectively. There will always be a leak. You could try 6 mil polyethylene liners but they will be unwieldy and expensive. 

By some miracle the current proposed setup may work, but it cannot be called an SWC or SIP system. Furthermore, unless you use a proper (and expensive) wicking medium you will end up with an anaerobic soggy mess perfect for rotting the roots right off the tree.

Alternatively, you may want to look up and trial an olla watering system using your nursery pots. Again this would mean acquiring unglazed clay pots for extra $$.

Dallas figs , good point about getting the entire area too wet. It would be no trouble at all to get a piece of "Funny" pipe in there for an overflow drain. . (Funny pipe is a 1/2" flexible pipe used in irrigation). It would slip right in with a couple of holes drilled in the pots. I don't need mesh as the holes that I would drill in the nursery pots would be as small as the mesh. (I was thinking of 3/8" mesh not like window screen mesh). Also the inner pot is upside down. FMD. I'm pretty sure Bill uses mushroom soil. I prefer mostly 50/50 pro mix HP and pine bark fines. For 20 gal I may add up to 25% compost or topsoil to stretch the mix. The water logged soil always in the water would get sour but seems to work for Bill. I know, it's weird.

Correct me if i'm wrong.. Your inner wick pot is upside down, but the reservoir pot is not.  Correct?  What's above the reservoir?

Correct. Picture a 5 gallon bucket (solid) upright with an upside down 2 gal bucket inside (perferated). Both pots at same height (level) At the very center would be clean water, the reservoir. Outside of that pot, between that pot and the 5 gal bucket would be my wick of soil and water. Above all of that would just be soil. No need for mesh seperation.

ahhh... i had it backwards..  i thought the very center was the wick.  I'm with ya now.

So the "funny" pipe will run from the center instead of where I put it in the picture above.  That's actually pretty clever.  Is the inner reservoir much smaller than the 5 gal?  I'd try to get one that is about 4" narrower in diameter.  That will give you about 2" ring for the wick and maximize the reservoir space.

Keep us posted on how it works out!

Now were on the same page. I'm with ya! (I noticed that you had the drain pipe stuck in the dirt). What I realized is that water would get some floating stuff in it and may clog a 1/2" pipe so a 1" PVC would be better. But now that that's hashed out, here's another idea. If you did not have the 6" perf pipe you could suspend a 2 gal pot by it's rim in the center. Pop it full of 1/4"-3/8" holes and you're good to go. (Yes my drain pipe should be higher in the bucket towards the lid. Lol)

Yep.. that should work too. 

Aaron,
Since you are starting with existing perforated planters, an idea may be to fabricate a simple Multiflow Hydronic System. All that's needed is one (1) level controller bucket (with float valve) and multiple wicking buckets. The wicking buckets are filled with sand and would be wicking and watering reservoir all in one. They would be placed inside the planter. In the attached video you will see the concept. All that is necessary is a "Level Controller bucket" with an installed float that is attached to your water supply.
http://www.youtube.com/watch?v=qC1GGzbdmG4

BTW the Earth box self watering automated system is built on this concept.
http://earthbox.com/earthbox-pdf/earthbox_watering_system_instruction_sheet.pdf

Instruction and diagrams (pages 2, 12 and 13 in PDF file) for the level controller bucket are available from http://alaskagrowbuckets.com/
in this PDF format...http://alaskagrowbuckets.com/alaska-grow-bucket-guide/
http://www.youtube.com/watch?v=6eRHbNIw3ZQ#t=82

You will have to calculate the optimal wicking surface area for proper water uptake. I have done some calculations in the past and on average the wicking surface area should be approximately 10% of the planters surface area.
 
The solid 5 gallon bucket would be lined with landscape fabric and filled with sand, the fill / drain pipe would exit the side of the container and can then be connect to the simple level control bucket. The system can be flushed or checked for proper operation by simply raising the level control bucket 6 - 12 inches above its normal height (the wicking bucket will flood and water will flow freely from the planter drain holes).
Good Luck.

I don't plan on covering the pots with plastic to keep out rain water. Because there are drain holes on the bottom of the 20 gal pots, I don't see the need. I will be irrigating all of the pots with 1/4" drip tubing. I currently have 150 pots with about 80 varieties with no plans of slowing down. Paying $30 each for SWP's or even $15 is getting out of hand. I already have to up pot 1/2 of my figs. The soil and fertilizer alone is enough. Pete. I don't see (at all) how that would be easier. I have very low cost or free materials and an existing irrigation system. Also, my pots do not all sit level, there is a slight hill. All things being equal and I had a huge level area that I kept them on and money was no object, I'd have them on a flood table regulated with moisture meters. Sorry.

I think the plastic on top is not just for keeping out rainwater.. it also reduces evaporation, so the top half of is staying too dry.  It keeps it consistent. 

Aaron,
The remote reservoir of the multiflow system is much easier to fabricate than individual multiple wicking / reservoir buckets and the containers could be grouped together to share a common level control bucket. Similar to a multi container Autopot system.
    
But, for your application the wicking/reservoir buckets can be built like the individual Alaska Grow Bucket and then water can be added (by your existing irrigation system) through the fill tube. The Level control bucket and its associated tubing would be eliminated, Similar to your design No. 2 in post #17 or the picture in post #24 or post #30. Good Luck.
 

Please keep us posted on your final design and implementation.

<edit> For a 24 inch Diameter (452.4 sq.in) container the cross section for the wicking tube should be approximately 8 inch diameter (45.2 sq.in).
18 in Diameter container...6 inch diameter wick tube.
12 in Diameter container...4 inch diameter wick tube.

Aaron, did you ever end up converting a 15-20 gallon nursery pot with holes to a SIP?  I would be interested to hear about the design you finally came up with.

Hi Adelmonto,
I hope your inner bucket is strong enough to hold the pressure from the dirt around it.
I hope your holes don't clog up.
To be honest, I don't see the purpose of the inner bucket .
Is your climate hot ? That would help dry the mix in the pot.
Is your climate not rainy ? If rainy, you'll be washing the dirt and losing the nutrients through the overflow - so definitively I would want to put a lid on the pot .
What is the height of the pot ? At a certain height the wicking power of the dirt will be inefficient to return the water to the surface of the dirt.
IMO, the key would be to put the pot on a sunny spot. If the pot is in a shady spot, I would expect the dirt to turn soggy and moist .

I've tried something like that with just putting an open bowl in the bottom of at tub as a reservoir. I couldn't tell when it was full and when I up potted I found that the roots had rotted in the reservoir. I have some 30 gal. tubs I use for small plants, peppers and such. They already have drain holes and I have been thinking of retrofitting them with a reservoir, but with closed top, feed and overflow tubes, and a net bag (like in the rain gutter system) for a wick. I would line the tub with weed excluder cloth because I've seen a site selling commercial pot liners that they claimed acts as an air pruner and stops root circling even though it's up against the side of a pot. I wouldn't use a 5 gal. bucket though. I'd cut a 2 or 3 gal. bucket off at 4-6 inches to give more root room above it.

[QUOTE=ADelmanto]So here's what I've been thinking of trying next year. I'm a landscaper and I have very good access to 15 and 20 gal pots. So what if I took a 20 gal pot and turned it into a kind of self watering pot, but instead of having the water in a larger (expensive) solid pot, I drop in a smaller solid pot where the roots could grow down to it. Let me know if you think this would work or not. :-)[/QUOTE] I was thinking of something similar but doing what Bill M does in the bottom of his pots and the putting the 20 gal nursery pot into a deep saucer.

I just found this link describing one approach to convert a container with holes to a SIP:

http://www.insideurbangreen.org/2011/07/converting-drain-hole-pots-to-sub-irrigated-planters-sips.html

Has anyone tried this?