Grow bags on concrete in the sun?

[Guest]

Has anyone had heat issues from grow bags sitting on concrete patios?
I got three 25 gallon grow bags on my patio. First time using this size and just sitting on concrete. And I have to say up front it’s tomato plants. With the heat starting to get up there I noticed when I stuck a finger in to check moisture the soil was still damp but kind of warmer than I expected. They ‘mater plants are about 16-18” tall and around noon they were noticeably wilting. Came back around after it started cooling off like yesterday. Could the concrete be radiating excess heat into bags enough to make a difference? I went proactive and ordered some gro pro plant risers in case. Last year in slightly smaller bags I didn’t see this problem. ?????

 

[TakenByTheSky]

Just my thinking, far from an outdoor expert but I know the root zone has its happy place in terms of growth. Too cold and it slows down, too hot it stops, and it absolutely hates it too wet, so yeah will they survive? Probably, will they grow to their full potential? Probably not. So as you can see there is many reasons to get them up off the ground and provide a little air gap where the air can flow and the water can drain and that helps the bags dry out from the bottom up.

 

[Guest]

Just my thinking, far from an outdoor expert but I know the root zone has its happy place in terms of growth. Too cold and it slows down, too hot it stops, and it absolutely hates it too wet, so yeah will they survive? Probably, will they grow to their full potential? Probably not. So as you can see there is many reasons to get them up off the ground and provide a little air gap where the air can flow and the water can drain and that helps the bags dry out from the bottom up.

Well it sounds feasible. Hope the plant elevators show fairly quickly. Not expensive but shipping sucks ass.
https://www.gro-pro.net/shop/product/gro-pro-nx-level-pot-elevators

 

[TakenByTheSky]

I use milk crates but I've thought of using plastic pallets for larger plants.

I've never seen plant elevators before I looked them up, I like that!

 

[Cmoon]

Heat stress m8, black buckets in direct sunlight react simular which need shielding, if you can gently get the bag off the floor an inch it will reduce the issue, in heat dont use cold water or expect shock, tepids good enough and if their drying out quickly several waterings a days required.


bests cmoon

 

[LizardMan]

Not concrete or patio stones but still middle of a driveway with limestone screenings.

25 gal fabric pots, only thing was they needed more water then the ones that were not baking from the radiant heat off the driveway.... They still produced i think the heat sink helped in the early season and late season. And some days they turned down from excess heat

Mid september after a rain