Taproot vs. fibrous roots, seed vs. cuttings

[gorbelly]

I recently came across this information while doing some research:

The tomato plant can have a fibrous root system or a taproot system depending on how the plant was grown. If the plant is grown from a seed, the plant will exhibit taproot organization, as shown in the photograph and drawing below. When the plant is grown from cuttings, a fibrous root system will form.

From UC Davis Plant Biology website

Is there a difference in plant vigor/success/productivity/etc. with a taproot organization vs. fibrous root organization? It seems to me that a taproot system would mean a plant with deeper roots, which seems like it would be less prone to water inconsistency issues, problems from soil temp fluctuation, etc.

[Gardeneer]

I don't think there will be a difference in plant vigor. Tap root is the nature's way to anchor the plant for stability. Or it can go deeper to find moisture in case of drought.

Gardeneer

[slugworth]

I will see this summer,I have clones of an heirloom that are going to be planted outdoors this summer.For indoor use no difference.Fibrous root plants if kept indoors until tall would make up for the lack of taproot by planting them deep.

[JLJ_]

There was research published on this in the early 20th century -- pretty thorough, as I recall, you might look around for it. I do have some of it saved somewhere, but haven't time to hunt until, um, about the end of this century.

But I believe a very long taproot developed early in the life of tomatoes planted from a seed at the location where they would grow, and that transplanting shifted the balance toward a more fibrous structure.

[Cole_Robbie]

It would depend on the soil. My sub-soil is compacted clay, and tomato roots just don't grow down into it very well. They tend to run sideways in the loose soil I pile up to make raised ridges.

[carolyn137]

Originally Posted by gorbelly

I recently came across this information while doing some research:



Is there a difference in plant vigor/success/productivity/etc. with a taproot organization vs. fibrous root organization? It seems to me that a taproot system would mean a plant with deeper roots, which seems like it would be less prone to water inconsistency issues, problems from soil temp fluctuation, etc.

The original,from which UC Davis took their information is here

http://soilandhealth.org/wp-content/...010137toc.html

Scroll down until you come to the Tomato Chapter.

This is the one that JLJ was thinking of and I've linked to it here and other places many times over the years.

Carolyn

[seaeagle]

Well I read the first few paragraphs from that Heirloom report and this is what I conclude

You will have a fibrous root system if you transplant which makes it even more important to plant those tomatoes deep.The only way to get a taproot system is sow seed directly or have a plant that comes up naturally.

I would prefer a fibrous root system anyway because of the clay base I have.Pretty black soil on top though.Great book by Weaver and Bruner

[Worth1]

Tap roots are for carrots.

Worth

[gorbelly]

Originally Posted by carolyn137

The original,from which UC Davis took their information is here

http://soilandhealth.org/wp-content/...010137toc.html

Scroll down until you come to the Tomato Chapter.

This is the one that JLJ was thinking of and I've linked to it here and other places many times over the years.

Carolyn

Great link, Carolyn. Thank you.

Interesting: it says that tomatoes that were not transplanted at all before planting out produced earlier and better. Yet most experienced tomato growers advocate transplanting seedlings multiple times, citing a more robust root system and better growth. Has there been new science on that that overturns what this book says, or is it really better, for those of us who are just growing for modest back yard gardens, to start out the seed in a large pot to begin with?

[carolyn137]

Originally Posted by gorbelly

Great link, Carolyn. Thank you.

Interesting: it says that tomatoes that were not transplanted at all before planting out produced earlier and better. Yet most experienced tomato growers advocate transplanting seedlings multiple times, citing a more robust root system and better growth. Has there been new science on that that overturns what this book says, or is it really better, for those of us who are just growing for modest back yard gardens, to start out the seed in a large pot to begin with?

I do consider myself to be an experienced tomato grower after growing some 5,000 plus varieties and also being raised on a farm where we had many acres of tomatoes and I never,but never potted up,as there was no reason to do so.

Sowed seed in 20 row professional inserts, take those seedlings and directly transplanted 6 packs,and that's it.When they are between 6-9 inches they get planted out after hardening off.

I did learn quite a bit from my farmer friend Charlie,where I took all my flats of transplanted ones to his greenhouses,he's a commercial grower.

And in CA many commercial places do direct seed into the soil, they grow mainly det or semi-det ones ,thin out and fertilize only with liquid fertilizer and it allows for much better machine harvested fruits.

One only needs to do ONE transplant to develop a fibrous root system,which is what is desired,not a tap root system for home growers,who,astoundingly,do not machine harvest.

Carolyn

[gorbelly]

Originally Posted by carolyn137

I do consider myself to be an experienced tomato grower after growing some 5,000 plus varieties[...]

I did say "most" . It certainly seems to be the conventional wisdom today that potting up is the best thing to do for seedlings, period. However, I'm wondering whether this is just a case of best practices--for practicality, space, cost of medium, etc.--for large-scale growers that has been mistakenly extrapolated to all growers, regardless of their scale.

Originally Posted by carolyn137

One only needs to do ONE transplant to develop a fibrous root system,which is what is desired,not a tap root system for home growers,who,astoundingly,do not machine harvest.

Carolyn

Does the planting out and burying deep constitute a transplant?

I was thinking that next year, I would do an experiment (too late for this season) in which I grow two of each variety, potting up one in stages as usual and starting the other in a larger pot and never transplanting until it goes into the ground, and seeing whether there's a difference.

[Cole_Robbie]

For soil-grown plants, I agree; it doesn't matter.

For container plants, I pot up several times. Maybe that is the confusion - container versus soil growing.

[JLJ_]

Originally Posted by carolyn137

. . . One only needs to do ONE transplant to develop a fibrous root system,which is what is desired,not a tap root system for home growers,who,astoundingly,do not machine harvest.

Carolyn

The does seem to be what older research found. The one situation where a taproot system *might* be a big advantage to home growers is in dry areas where irrigation possibilities are limited -- a common situation in much of the west. Worth investigating in areas where climate makes direct seeding possible, I think.


That was a great link you posted!

Though I believe what I was thinking of was a couple of older publications devoted to tomatoes -- haven't found them yet -- maybe someday. Lots of good info on growing "real" vegetables in older publications produced by competent sources.

[slugworth]

I had seeds and cuttings from an heirloom that showed drought resistance,so it should be interesting this summer how they perform head to head.

[Worth1]

None of this is set in stone.
A root can go down a wee bit hit something and take off in just about any direction or split up.
What I have noticed to be the biggest complement to planting is to go from the first transplant from the seed starting tray to the next one is to plant the plant deep.
This in effect gives the plant some stability as I have seen some just flop around if I didn't do it.
As for direct planting seeds there is just no way that is going to happen where I live.

The few that have survived like this from volunteers had shallow tap roots in soft soil and the plants flopped around.
Worth