Research reveals container size matters - Pics

Ohiofem(6a Ohio)July 5, 2012

Interesting research from Germany tells us what many suspected: Plants never thrive when they are potbound. Read about it in BBC Nature News:

"Plants grown in pots never reach their full potential, images of their roots show. A medical imaging technique called magnetic resonance imaging (MRI) has been used by researchers to capture plant pot root snapshots. The pictures reveal that the roots 'sense the size of the pot' and restrict the growth of the plant."

Here's an MRI of plant roots:

Here is a link that might be useful: Read the article here

Thank you for reporting this comment. Undo

Which is why the bigger the pot the better.
It also "seems" as though the "Smart Pots" may lessen the plant sensing the size of the pot.

    Bookmark   July 5, 2012 at 2:25PM
Thank you for reporting this comment. Undo

As I mentioned on another thread, I'd be curious to know if this was based on peat based or other type of soil. I always inspect roots and have seen this root pattern in peat based soils, but in 5:1:1, the roots are more evenly dispersed and less likely to be rootbound. Is the what you get when roots are constantly looking for air? I suspect so.

    Bookmark   July 5, 2012 at 2:29PM
Thank you for reporting this comment. Undo
dickiefickle(5B Dousman,Wi.)

Just normal survival genetics .Roots spread outward to gain as much area as possible(this helps to make them stable and claims their territory ) then the roots can work downward from their broad territory.
This is a good thing and is why moving (growing) seedlings thru different sized pots before transplant to final garden area helps to build a strong root network

    Bookmark   July 6, 2012 at 1:59AM
Thank you for reporting this comment. Undo
tapla (mid-MI z5b-6a)

I firmly agree that bigger is better - as long as you're not introducing a soil-related limitation (over-potting) by going bigger. It really seems that the study overlooked the most basic explanation for changes in root behavior; that being that all parts of a medium in a container don't provide the same growing environment. Roots don't "look" for moisture or nutrients - they simply grow better where conditions are more favorable.

I think reaching the conclusion that roots 'sense' the container walls while ignoring other potential causes for changes in root behavior, and especially not accounting for other influences on root behavior creates an error in logic called questionable cause or a post hoc fallacy. If Joe gets scratched by a cat today and dies tomorrow, you can't logically say with certainty that Joe died of cat scratch fever.


    Bookmark   July 6, 2012 at 11:35AM
Thank you for reporting this comment. Undo

Take a look at the YouTube videos of Bobby, AKA Mhpgardener:

He grows tomatoes in grow bags in his hoop house, and they grow up to the roof - about 13 feet. Then he lets the twine down to let the vine keep growing up. This researcher says that any restriction at all on pot size affects plant growth. If I could grow tomatoes like Bobby, I'd be happy for that kind of 'restriction.' ;-)

    Bookmark   July 12, 2012 at 2:47PM
Thank you for reporting this comment. Undo

My train of thought goes immediately to "medium matters first", and not to pot size... though, with a well thought out substrate, one can grow easily in a larger pot, and over-potting isn't such an issue.

Cramped roots in small pots... or potbound plants... only behave the way they do because they sense impending issues, and the first genetic instinct is to flower and reproduce to move the DNA into the next generation before it's too late.

    Bookmark   July 13, 2012 at 1:05PM
Thank you for reporting this comment. Undo
greenman28 NorCal 7b/8a

Well said, Jodi! :-)


    Bookmark   July 14, 2012 at 3:19PM
Sign Up to comment
More Discussions
Long Term Potting Mix Recipe - Alternative to Gritty Mix
Hi everyone, I'm a new gardener from Perth, Western...
My New Raised Container Garden - Thanks for all the Help
This is really more of a conversational post. No real...
Cliff Pruitt
Why can't I grow vigna caracalla? Can you?
Hi Everyone I'm in z11 and took a while to get my hands...
RE: Introductory post-C.S-W.M&RXXI 1-27-15
Hi everyone, In my very 1st post, I described how by...
Potting into Air Pots, root length question
Hello all, My question is, air pots are supposed to...
stickstring (Northern California 8b)
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™