Grow Bags & Capillary Mats

newtraditionsfarm · December 14, 2012

Hi Folks,

I have a 40' x 100' hoop-house that was full of sun golds last year, and I'd like to give the soil a couple years rest from nightshades and was considering growing some plants in containers.

Would it be possible to use long stretches of capillary mat to 'sub-irrigate' a 4' x 100' "bed" of 10 or 15 gallon grow bags? I would most likely have an additional drip system to supplement watering on top of the bags.

I was thinking of digging a shallow 'trough' with my tractor, laying landscaping fabric on top of it (and perhaps an additional layer of painters plastic) and laying the capillary matting on top of that, with each end dangled into a large reservoir of some kind (110 gallon stock tank?)

Here's the capillary matting I was looking at: http://www.farmtek.com/farm/supplies...;pg106223.html

Thanks & let me know your thoughts!

Cole_Robbie · December 14, 2012

Wouldn't the capillary mat be unnecessary? The media in the bottom of the grow bag would wick up water without the mat. Capillary mats are typically used in hydroponics when there is no other media - the roots live in the mat.

I want a setup like you're talking about, but it's all the problems I see that keep me from it. What you're describing is basically a flood and drain system, except without the drain part, which I think you'll need. You'd have to put exactly the right amount of water in each time, or else your roots would get waterlogged and rot. You need a drain, or a sump pit and pump to remove the excess.

Anything the sun hits with nutrients and water on it is going to grow green slime right away, so you'd need to deal with that problem somehow. Either you block the light, or you don't let any unnecessary space get wet. If you get wet spots and slime, you'll breed fungus gnats immediately, and maybe foliar disease, too. I would want a lightproof box to set the grow bags into, maybe made of foil-faced insulation sheets. I will probably experiment with that idea with my bucket plants for the sake of keeping the roots cool when it gets hot.

newtraditionsfarm · December 15, 2012

Actually, here's my thought: Instead of directly flooding the 'trough', I can keep the capillary mat hydrated by having it's ends draped into two reservoirs. This would solve the problem of standing water, mold, whiteflies, etc. The additional plastic layer underneath the matting would simply serve as a moisture barrier so that the ground doesn't wick away all the moisture from the mats.

newtraditionsfarm · December 15, 2012

Also, a thought: To increase wicking between the mats and containers, I could place an additional small cut piece of capillary mat at the bottom of the grow bag with direct contact to the mat underneath.

Also possible: Cutting a round piece of capillary mat to rest on top of the grow bag media like a piece of plastic mulch. This might solve some of the problems I've encountered in the past with container drying in the heat of the hoop house.

Cole_Robbie · December 15, 2012

You could use covered gutters and wicks. Stick the wick up the bottom of the grow bag, set it on top of a hole in the gutter, then flood the gutter.

December 14, 2012	#1
newtraditionsfarm Tomatovillian™ Join Date: Oct 2010 Location: Kankakee, IL Posts: 59	Grow Bags & Capillary Mats Hi Folks, I have a 40' x 100' hoop-house that was full of sun golds last year, and I'd like to give the soil a couple years rest from nightshades and was considering growing some plants in containers. Would it be possible to use long stretches of capillary mat to 'sub-irrigate' a 4' x 100' "bed" of 10 or 15 gallon grow bags? I would most likely have an additional drip system to supplement watering on top of the bags. I was thinking of digging a shallow 'trough' with my tractor, laying landscaping fabric on top of it (and perhaps an additional layer of painters plastic) and laying the capillary matting on top of that, with each end dangled into a large reservoir of some kind (110 gallon stock tank?) Here's the capillary matting I was looking at: http://www.farmtek.com/farm/supplies...;pg106223.html Thanks & let me know your thoughts! Last edited by newtraditionsfarm; December 14, 2012 at 04:02 PM.

December 14, 2012	#2
Cole_Robbie Tomatovillian™ Join Date: Jun 2012 Location: Illinois, zone 6 Posts: 8,407	Wouldn't the capillary mat be unnecessary? The media in the bottom of the grow bag would wick up water without the mat. Capillary mats are typically used in hydroponics when there is no other media - the roots live in the mat. I want a setup like you're talking about, but it's all the problems I see that keep me from it. What you're describing is basically a flood and drain system, except without the drain part, which I think you'll need. You'd have to put exactly the right amount of water in each time, or else your roots would get waterlogged and rot. You need a drain, or a sump pit and pump to remove the excess. Anything the sun hits with nutrients and water on it is going to grow green slime right away, so you'd need to deal with that problem somehow. Either you block the light, or you don't let any unnecessary space get wet. If you get wet spots and slime, you'll breed fungus gnats immediately, and maybe foliar disease, too. I would want a lightproof box to set the grow bags into, maybe made of foil-faced insulation sheets. I will probably experiment with that idea with my bucket plants for the sake of keeping the roots cool when it gets hot.

December 15, 2012	#3
newtraditionsfarm Tomatovillian™ Join Date: Oct 2010 Location: Kankakee, IL Posts: 59	Actually, here's my thought: Instead of directly flooding the 'trough', I can keep the capillary mat hydrated by having it's ends draped into two reservoirs. This would solve the problem of standing water, mold, whiteflies, etc. The additional plastic layer underneath the matting would simply serve as a moisture barrier so that the ground doesn't wick away all the moisture from the mats.