Grow Mediums Let's talk about... roots

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Question: Do plants always build as big a root system as possible, or do they only build as much root as necessary?

The reason I'm posing this question is as follows:

I've got a 9 pot RDWC system and on my previous grow the root system was WAY bigger than on my current grow at the same number of days into the grow. Same strain (Mephisto Chemdogging) but very different levels of root development.

Now, "above ground" the plants are almost identical in terms of development and if anything the current grow is healthier. I'm hoping that I have a better nutrient environment this time round (last time was sterile, this time I have good bacteria) and so the plants need less root to maintain the same level of growth. Does this sound plausible?

Basically, I'm trying to convince myself that just because the roots are less developed, doesn't mean this grow will not be as good as the last one - which was heavy yielding (just over 900g from 9 plants).

Would love to hear your AFN thoughts...

 

[Simplicio]

Question: Do plants always build as big a root system as possible, or do they only build as much root as necessary?

The reason I'm posing this question is as follows:

I've got a 9 pot RDWC system and on my previous grow the root system was WAY bigger than on my current grow at the same number of days into the grow. Same strain (Mephisto Chemdogging) but very different levels of root development.

Now, "above ground" the plants are almost identical in terms of development and if anything the current grow is healthier. I'm hoping that I have a better nutrient environment this time round (last time was sterile, this time I have good bacteria) and so the plants need less root to maintain the same level of growth. Does this sound plausible?

Basically, I'm trying to convince myself that just because the roots are less developed, doesn't mean this grow will not be as good as the last one - which was heavy yielding (just over 900g from 9 plants).

Would love to hear your AFN thoughts...

Big plants have big root systems, and yield big.
Little plants have little root systems, and yield little.
An alternate explanation about why the roots are small is that they have trouble growing in the non-sterile environment.
Yield might be less, but who knows.

 

[LaoWhoo]

Have read that ginormous roots are actually detrimental, that there's an optimal balance to be struck there. Sure, you see lotta posts/pics about gigantoid root balls, but...I'll try to dig up the article but it basically said that, outdoors at least, the roots only wanna travel as far out as the canopy overhead. Granted that's pretty big, depending.

 

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Thanks for getting involved with my roots thread @Simplicio - I hope it is something people want to discuss.

Big plants have big root systems, and yield big.
Little plants have little root systems, and yield little.

Totally agree with you there and the thing that is puzzling me here is the two grows are identical in terms of plant development, size, health, everything basically - except the previous grow had more root mass.

 

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Have read that ginormous roots are actually detrimental, that there's an optimal balance to be struck there. Sure, you see lotta posts/pics about gigantoid root balls, but...I'll try to dig up the article

This is what I am hoping! Would really appreciate it if you can find that article.

My theory is the plant creates the roots it needs and no more. I mean, why waste energy on massive roots if it is not necessary?

 

[LaoWhoo]

Here's sumthin about the ratio of uptake to photosynthesis...still lookin

https://www.sciencedirect.com/science/article/pii/0040580984900078

And a model simulation...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213091/

...which found, "Increasing root length, for example due to increasing LRBD, reduces the water uptake per unit of root length and thereby possibly reduces the nitrate uptake per unit of root length as well."

Lotta good notes/references following this white paper

Similarly, this paper, "Optimal Leaf-to-Root Ratio and Leaf Nitrogen Content..." seems to echo same finding

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3134483/

 

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Very interesting @LaoWhoo - many thanks. I just had a quick glance at the model simulation paper and it sounds as though roots from the same plant can also start to compete with each other if there is too much root branching density.

I'm still hoping that my smaller roots and same sized plants in this grow somehow means my environment is better. Thanks again my friend.

 

[LaoWhoo]

Hope so too. That was my intention, anyhoo. Wonder whether you'll feel compelled to prune summa the larger ones?

 

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Hope so too. That was my intention, anyhoo. Wonder whether you'll feel compelled to prune summa the larger ones?

Yes, I pruned the Chemdogging plants today - removed low-potential side branches to encourage all their energy into large colas.

 

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To show what I'm discussing here - a couple of pictures.

Roots from previous Chemdogging grow:

Roots from current Chemdogging grow:

Both pictures were taken at around day 23 give or take a day or two.