The standard and special window screens discussed above are all made from strands with an outer vinyl coating. Pure vinyl plastic is stiff and brittle. Flexible vinyl has added plasticizers; these may slowly leach out and be toxic to plants (or the people that eat them). Potentially toxic fire retardants may be added. One brand of screen, "super screen", has an anti-microbial additive. If the product is imported from China; it may have lead (they can't put lead into toy exports anymore!, smile-wink).

I would be more at ease using a polyethylene or polypropylene based screen or shade material. These require additives too, but not as many as vinyl. I'm not afraid of additives such as most UV inhibitors or most colorants (some of these are approved for food grade plastics).

I noticed that one of our "gurus", Al ("tapla"), is in the buisness of window screens. Perhaps he can make the proper inquiries to the screen manufacturers and put my mind at ease.

Maybe I'm just a worry wort!
I'm not yet ruling out vinyl-coated fabrics!

The following link is for "Leno Mesh Produce Bags" made from polypropylene fiber. I'm not talking about "onion" or "potato" bags whose mesh is way too big. If you fold the bottom right, these bags have a lot of potential at only 30 cents a piece!

I don't know if these have enough UV-Inhibitor to survive a growing season in the sun. I also don't know its mesh size. (A pore of 5/64 inch is used in one of the products from www.rootmaker.com .)

If you google "mesh produce bags", there is another type of weave pattern called "raschel", that may also be suitable. Raschel looks similar to knitted greenhouse shade cloth. So far in my search, the suppliers of raschel bags sell in packs of thousands; too many for me!

Wal-Mart & other similar stores have mesh laundry bags (hampers and lingerie bags). These are about 1/4 inch mesh, which is probably too large in terms of soil leakage and water loss.

Here is a link that might be useful: Leno Mesh Produce Bags

Hey Npthaskell, glad to see you are interested in this subject. Did you see the follow up post I made? Just in case you didn't, here it is:
http://forums2.gardenweb.com/forums/load/contain/msg101458547980.html

I hate to admit it, but I didn't continue this project much further. I never received my large stock of young trees that I had planned on potting into the DIY airpot. So, I let the idea fade away and never continued it.

However, earlier this spring I slightly revisited the idea, but with a different approach. I got to thinking about Al's suggestion of using mesh pots, and it actually seems like a better alternative if the funds are available (unfortunately for me, they're usually not available).

Not to try and change your mind on the subject, but if you're interested you can run a simple search using "Net Pot" and come up with a huge variety.

I would suggest using these net pots if you have just a few plants you'd like to experiment with. But if you have several plants then the DIY approach would be a more economical choice. I'll probably return to this idea later this summer as I'm planning on having approximately 30 to 50 seedlings of some maples that I want to play with. Buying that many net pots, even the small ones, would NOT be economical for me. So I'll be making several airpots if everything goes according to plan this year.

Back to the DIY approach.... A few things I learned along the way:
The fiberglass screen that I was able to get my hands on was just way too flimsy and flexible. Wouldn't hold up very well. Though you may be able to find some stronger than what I had.

Never could perfect the "mold" technique.

Also couldn't ever perfect the "vertical cut" technique that was suggested by another member. However, I think success using this technique really depends upon what you're using to make the basic shape. I was using things around the house to make the basic form from which to make the appropriate slits in the sides. Never did find anything that worked well. But now that I think about it, you could probably get away with not using any type of mold at all.

Here's what I'm thinking for this approach... Cut out a relatively large square from the screen. Then cut slits diagonally from the four corners towards the center. But don't cut all the way to the center, instead stopping approximately 4 to 8 inches from the center (all of this depending upon the size you're going for). Then fold the newly cut "flaps" together, overlapping them and securing them into the final shape you want (square or circular). Secure with staples (that's easiest thing to use instead of sewing monofilimant).

Hard to describe without pictures but maybe you get my gist. I just tried it using a piece of paper. The flaps overlap quite a bit, so you would actually be using a lot of screen. However, this would help to reinforce the sides making them stronger. Also, this way you wouldn't have to "attach" the bottom to the sides. It would be very easy and not too time consuming.

Hmmm..... Okay. My curiosity is back on this subject again! I think I'm going to have to experiment with this approach later this afternoon as this was something I never tried before.

If I can muster the willpower to try it using real screen (I've got plenty left), I'll post back with my results and hopefully some pics later today.

Now concerning those produce bags.... That seems VERY interesting! Not biodegradeable, already in some basic form, and very cheap! Sounds waaaaaay too easy :)

I think it's a good idea! If you or anyone else decides to try them, please let us know how it goes!

I'm not as versed on this subject as you all are, but just yesterday I just happened to see in one of my catalogs, Growers Supply, a product that could be used for grow bags. Their use is actually to fill up and use for erosion control. They are 12 or 16" in diameter and can be bought in different lengths. Although they jump from 10 or 20 feet to 100 feet. I have a rooftop garden and really no way to use these as hanging bags. I'm looking into using them to grow strawberries in and lay out on the sloped portion of my roof. My hesitation is I don't know how I'd harvest the berries without walking around on my roof and hubby says that might make it start leaking. :(

There's also a product you can buy in long tubes like that that they use to make sand bags for flooding. I don't know if they totally seal in water. It's very similar to that stuff you buy bulk grass seed in, kind of woven plastic. People that build those rammed earth houses use it. I think the architect famous for it name is Nadar Kalili or something like that. I think there's a company in Memphis that makes it. I'll see if I can find anything out on it.

veggievicki wrote:

> ...a product that could be used for grow bags...erosion control

LOL, it is mentioned in my parallel thread (link below). I believe that FarmTek (mentioned in my other post) and Growers Supply (mentioned by you) are the same company.

Here is a link that might be useful: Sandbags & other bags

veggievicki wrote:

> ...long tubes ... earth houses...
> the architect famous for it name is Nadar Kalili
Thank you so much for this lead.

Retailer is Cal-Earth; huge minimum order; degrades in sunlight (buildings are plastered to protect the bag).

http://www.calearth.org/bagorder.htm

> I think there's a company in Memphis that makes it.

Manufactured by Jumbo Sack, St. Louis Missouri?

Here is a link that might be useful: Super Adobe Bags

I did not see your follow up thread, in which you show your wire window screen pots. Thank you for the link; I will study these in greater detail.

> if you're interested you can run a simple search using "Net Pot"
> and come up with a huge variety.

When I think of "net", I think of a mesh fabric used for onions or potatoes (or garden bird netting), with huge holes (about 1 inch or more) unsuited for pots. Silly me, never thought of googling "net pot". So far, most of what I see are pots I have previously seen at hydroponic and pond web sites. I'll keep looking.

zeckron wrote:

> concerning those produce bags....
> Sounds waaaaaay too easy :)

Must be a catch, huh? You may be right.

I got a very quick response from Gourmet Seeds International.

The mesh holes are about 1/8 inch. I think that would be OK, but 1/8 inch seems to be my upper limit.

They are "not UV rated". I don't know what that means, either:

1. They have some UV-Inhibitor, but the manufacturer never advertised, tested, or "specified" (ie., "rated") the degree of protection. ... or

2. "not UV rated" means no UV-inhibitor at all.

Zeckron wrote:

> The fiberglass screen that I was able to get my hands on
> was just way too flimsy and flexible.

That is why I suggested Pet Screen. Not as rigid as wire mesh, but not as flimsy as standard coated fiberglass screen.

> cut slits diagonally from the four corners towards the center.
> But don't cut all the way to the center

If you go to a fabric store, they sell patterns for sewing clothing (eg from "Vogue"). The patterns are like big blueprints that you pin onto the fabric and you cut along the lines drawn on the paper.

Your "sewing pattern", as described above, is much more elegant! ;-)

I am more interested in slim and tall pots. Your idea is perfect when the height of the pot is about equal to (or less) than its width.

Zeckron posted a thread with pictures of his wire mesh pot, and I now see where he is coming from.

> The fiberglass screen that I was able to get my hands on
> was just way too flimsy and flexible.

The way I approached the issue is that a well packed column of soil would put tension on plastic mesh, and then tension on the mesh feeds back to support the column of soil.

Zeckron's approach was to build a pot that is self-supporting when empty. My previous thinking on the subject would yield a pot that collapses when empty. Zeckron's approach is more like those "Air Pots" imported from Scotland, or the "Root Builder II" equivalent from Rootmakers.

Zeckron's approach requires a more rigid mesh than I was ever considering. Silly me; suggesting a switch, from standard fiberglass window screen, towards heavy duty pet screen, may not suffice for a self supporting pot.

I have another prejudice against aluminum window screen. In my mind, wire mesh equals metal, and metal equals corrosion. This is somewhat irrational, as aluminum is supposed to be resistant to corrosion. But not completely irrational, as my aluminum garden tools get a white powdery corrosion material on their surfaces.

Another prejudice in my mind: wire mesh equals dull scissors; ......

..... and equals bloody scratches all over my arms, LOL!

Is this plastic mesh rigid enough for you, Zeckron?

Here is a link that might be useful: Back to the bat cave, Robin! LOL!

The 1/8 inch mesh in the middle of this link should do it. It will need bark to keep the soil from leaking out.

Here is a link that might be useful: This should stop the Penguin, Robin!

President Bush (the first) drew a line in the sand.

Sadam, your invasion of Kuwait will not stand..... but this pot sure will!

Here is a link that might be useful: The Answer My Friend, is Blowing In The Wind

Back to flexible solutions. For illustration only; these nylon meshes are not necessarily resistant to UV. A black UV coating, aka asphalt, is suggested. A potential toxicity of asphalt worries me.

That's "Seine", not "Sign", Mister!

And don't call me Babe, you Jerk!

Here is a link that might be useful: And stop looking at my fish net panties, you pervert!

... of "micro mesh" for building pots...

Here is a link that might be useful: ... or is a roll of mesh just a great

oops, that last link should have read (with some clarification added)

... or is (carrying) a roll of mesh (out from a fabric store) just a great "chick magnet"

My local Wal-Mart is selling Shade Cloth, "Coolaroo" Brand, available as either 70% or 90% shade shade factor. Coolaroo claims at least 10 years of UV resistance. I believe that Coolaroo is mostly an Aussie brand (manufactured in China and sold worldwide), so it is usually promoted as protecting people from excessive UV exposure.

I really don't understand why Aussies worry about skin cancer; I just thought that Crocadile Dundee would just pull out his 12 inch knife and, all by himself, dig out any funny looking moles saying, "Ah melanoma, no big deal."! The late Crocadile Hunter (may God have mercy on his soul) would just hold out his kid in front of a crock saying "Here crocky, here crocky, bite out that melanoma, that's a good crocky, that' it". And any suburban Aussie, would just rub their pet toxic cane toad above any melanoma. Oops, I digress from the topic of this post. Sorry for the American stereotypes of Aussies.

The Coolaroo display box also sells accessories, such as a sewing kit with a roll of black UV-resistant (my assumption) cord plus a special sewing needle. Shade cloth is available in two forms: woven or knitted; the Coolaroo product is knitted and does not fall apart if you cut it.

I purchased a roll of green 90% shade. I attempted two methods of fabrication: sewing or silicone glue (caulking). Using the Coolaroo sewing kit with their 90% shade cloth is quite difficult. Both their cord and needle are just too big; in contrast, their needle and cord should be fine for the 70% shade cloth. Sewing the 90% shade with a smaller needle and a more light weight cord, or using an aluminum wire, are alternatives that may work. Using sticks of hot glue melt may work; but the sticks carried by Wal-Mart are not resistant to UV, as far as I know; I have not tried them for that reason.

I also fabricated cylinders by pumping 1 or 2 strips of silicone caulking onto a two inch wide strip of the fabric, and pulling the fabric around over the silicone caulking and pushing down to form a 2 inch wide glued seam. There was plastic film underneath the seam to protect the garage floor from silicone. I pushed a seam roller (ie., those used for wall paper) over the glued joint. The pressure from the seam roller causes the caulk to ooze out from both layers of shade cloth- the two strips of plastic film intercept this ooze to form a thin layer of silicone on both outer surfaces of the seam. I soon remove the top plastic film so that air will induce the silicone caulk to cure. Once the silicone caulk cures, I remove the second roll of protective plastic film. Note that silicone does not glue the polyethylene (or polypropylene) shade cloth per se. Rather, as the silicone oozes around the plastic threads, a continuous matrix of cured silicone forms a mechanical layer that physically traps the two layers of shade cloth together.

Gee... I'm going to have to photograph this gluing process to explain it. Be careful with the silicone. Some tubes, especially those for bathtubs, contain a biocide to kill mildew; who knows what that will do to plants or those that eat the plants. Silicone, as far as I know, is inherently resistant to mold; but silicone is not inherently toxic to mold, so mold can grow on top of silicone. Nothing prevents mold from growing on top of silicone in a bathtub, unless controlled release biocide is added. Silicone for aquariums would be best, but may be pricey. Since Wal-Mart didn't have the Aquarium Silicone; I bought the "all purpose" tube for $2.65, and a cheap caulking gun.

The silicone method is the easiest method of fabricating cylinders of shade cloth from pieces cut from the roll. Now I have to figure out how to fold one end of the cylinder into a bottom of the pot. Either that, I cut out a circle and attach it to one end of the cylinder. Stay tuned for further adventures with shade cloth.

The shade cloth (Coolaroo brand - 90 % shade) resists folding, so fabricating the bottom of the pot by folding in one end of a cylinder, is quite difficult. Sewing a circular bottom onto one end of the cylinder is much easier, even with Coolaroo's own brand of thread and huge needle. It is a little time consuming, but can be done while watching TV.

Insect Screening is widely used for window, corridors, industry disposing equipment, sieves, filters, etc.

Mesh:4X14 14X16 16X18 18X18
Standard wire gauge: BWG31,32(0.254/0.229mm)
Roll size: 3'X100' 4'X100' 1X25M 1.2X25M 1X30M
Color:
Enamelled iron netting:Green or dark green
Plastic-coated iron wire netting: Green, blue,etc.
Fibreglass wire Netting: Available in different colors.

pls feel free to contact with me if you have an interst of above products.

Here is a link that might be useful: insect screening

I haven't tried it, but what about landscaping fabric? Its pretty cheap (especially for this purpose) uv resistant and rated up to 30 years.

Publix is giving away a reusable grocery bag with a minimum order. Material looks light, most likely won't last long. But for free..................................

One question about these Publix bags, they come with what looks like a rubberized cardboard bottom to strengthen the bottom of the bag for its original purpose. Is it best to dump this piece?

I was just looking at a Sunflower Market bag that had a bottom and I think it will work for spuds. I took out the hard bottom. The bag measures 12 x 12 x 8 so might hold one potato? Or should I try 2 spuds in the bag? Never did this before. But the bag was free when a new store opened and I have tons of grocery cloth bags.