Mesh grow bags in garden.

March 7, 2012 2:59 PM

I was interested in growing vegetables in mesh produce bags. It seems to be the ideal way to grow plants. Good drainage, good aeration and able to setup anywhere. Any downside to growing in mesh produce bags versus plastic buckets?

I've grown veggies in sip's "Sub Irrigated Planters" with some success. Using a combination of perlite, compost and sphagnum peat moss as a grow media I've enjoyed good crops of tomatoes, peppers and eggplants.
My biggest concern was watering. Can the mesh produce bags be placed in a shallow water reservoir without over watering the plants?

posted by boby to Home & Garden (6 answers total)

Best answer: I think your main difficulty with what you propose is keeping the soil moist enough. My experience with hanging baskets leads me to look very suspiciously at anything that exposes as much soil surface to air as would a mesh bag; drying and heating would both happen much more quickly than in other forms of container.

Try it out by all means, but I think that for best results you will probably want some form of liner inside the mesh bag walls (the floor should obviously stay open). Ordinary plastic shopping bags with the bottoms slit open would work for a while, but the sun eats those very quickly. Black polythene builder's plastic would work better, I think.

If you sat your bags in a shallow reservoir, I would expect to see too-wet soil at the bottom and too-dry soil at the top.

Sub irrigation via wicks is a very pleasing idea, and the lack of visible irrigation infrastructure makes it visually neat, but in my experience it will always suffer from root infiltration and silt buildup and need regular disassembly and cleaning. It's pretty hard to go past low-rate continuous surface drip watering, with a decent inline particle filter supplying small black distribution tubes and an adjustable dripper outlet next to each plant, for effective low-maintenance small-scale irrigation.

Try incorporating shell grit into your next perlite/compost/moss mix; you may get another season out of it. Plant roots mine minerals from the soil by exuding small amounts of acid, which the shell grit will help neutralize.
posted by flabdablet at 5:18 PM on March 7, 2012

I'd say flabdablet is right on the money, but expresses it much better than my initial, "oh, wow, look at all that water loss through the mesh, that's TOTALLY going to dry out really fast up top." So I'll just nod at what flabdablet said and go, "MMMMhhhmmmmm, that's right."
posted by theplotchickens at 6:24 PM on March 7, 2012

A blogger I read has been experimenting very successfully with a home-made version of this, she calls them grow cones or SIBs, and she makes them out of landscape fabric, which you can buy in a 100 ft roll for $17:

http://eatingoffthefoodgrid.blogspot.com/2011/08/cone-garden-and-bsf-update.html
http://eatingoffthefoodgrid.blogspot.com/2011/08/grow-cones.html
http://eatingoffthefoodgrid.blogspot.com/2012/01/lettuce-trees-and-sibs.html
http://eatingoffthefoodgrid.blogspot.com/2012/02/how-to-make-sibs.html

She places them in a reservoir or pot that is filled with pebbles and fills it with water up to a certain level so that the roots aren't too wet, and there is still opportunities for aeration. She also lets them dry out every once in awhile to decrease mildew and such. I've made a couple and plan to try them out soon.
posted by permiechickie at 8:02 PM on March 7, 2012 [3 favorites]

Are you going to put them in something opaque? Roots + light = no good.
posted by momus_window at 8:22 PM on March 7, 2012

As others have mentioned I think evaporation from so much perforated surface area will be a problem, and you're going to get localized concentrations of salts where that evap is occurring. I did something similar using perforated plastic bags (like the kind artisan bread loaves come in) and perlite as a medium, but I covered the whole thing with black plastic sheeting to prevent algae and evaporative loss.
posted by werkzeuger at 6:51 AM on March 8, 2012

Response by poster: Thanks for all the advice.
posted by boby at 8:50 AM on March 8, 2012