Eucalypt tap-root and lateral root growth.

[Fluorine]

Hi Guys,
Have recently purchased numerous eucalypt tubestock and have directly planted into the ground. Question, is the tap-root my friend or should it be restricted by an impervious or slightly pervious layer buried beneath the plant in order to stimulate lateral root development? Does one increase lateral roots and thicken the trunk of the plant if the tap-root growth is stifled? There has been some very interesting discussion about colander use by Ray and others; based on such reasoning it seems this is the case, unsure if this was in specific reference to natives however. Interested in peoples experience/thoughts/ideas.

Thanks, Fluorine.

[lackhand]

I don't have tons of experience with eucalyptus, but generally taproots are not your friend in bonsai. The shallow containers require lateral root growth for good health, not huge taproots. This is indeed one reason for growing in colanders, because once the roots hit the air they will not grow further, and growth will occur in other directions.

I'll leave it for the eucalyptus experts to say whether you should chop the taproot when repotting or not. Good luck, and welcome to the forums!

Also, I have to ask since you chose the name Fluorine: are you a chemist or scientist?

[Rory]

Well, I subject my Eucalyptus seedlings to the school of 'harden up'. By that, I actually cut off the tap root at the start. Initially I lose about 10% of stock, but the survivors.... they are usually quite tough and do well. Obviously if there is simply just 1 tap root and the roots don't start to branch off until a long way down then you will need to get the tap root into a tiny restricting hole, and force roots from the base. I find that it has no effect on restricting the growth of the seedling any more than pruning roots on a non tap rooted seedling. Of course, ground planting any tree will significantly increase the girth, but it will further promote tap root related problems (for bonsai that is).

[GavinG]

You may find that root work is best done when it's hot - Nov/Dec, followed by lots of water. Definitely dig each year to root prune, otherwise the roots get long, thick, and fatal to dig.

Gavin

[Fluorine]

I don't have tons of experience with eucalyptus, but generally taproots are not your friend in bonsai. The shallow containers require lateral root growth for good health, not huge taproots. This is indeed one reason for growing in colanders, because once the roots hit the air they will not grow further, and growth will occur in other directions.

I'll leave it for the eucalyptus experts to say whether you should chop the taproot when repotting or not. Good luck, and welcome to the forums!

Also, I have to ask since you chose the name Fluorine: are you a chemist or scientist?

Thanks Karl, valuable information. I think I might save the colander growing for those eucs that require a more free draining soil. The soil out here is clay rich.
You guessed it! A chemist, I am. Hope no one holds that against me.

Cheers, Fluorine.

[Fluorine]

You may find that root work is best done when it's hot - Nov/Dec, followed by lots of water. Definitely dig each year to root prune, otherwise the roots get long, thick, and fatal to dig.

Gavin

Thanks Gavin.

[Fluorine]

Well, I subject my Eucalyptus seedlings to the school of 'harden up'. By that, I actually cut off the tap root at the start. Initially I lose about 10% of stock, but the survivors.... they are usually quite tough and do well. Obviously if there is simply just 1 tap root and the roots don't start to branch off until a long way down then you will need to get the tap root into a tiny restricting hole, and force roots from the base. I find that it has no effect on restricting the growth of the seedling any more than pruning roots on a non tap rooted seedling. Of course, ground planting any tree will significantly increase the girth, but it will further promote tap root related problems (for bonsai that is).

Thanks bonsaibuddyman. I have seen some members post on the use of CDs for just that purpose. Will have to keep that in mind when I dig them up in a year's time.

Regards, Fluorine.