I apologize if this has been answered a million times. I did a brief search and still had some questions. I am growing some trees from seed. At the moment I have a few honey mesquite, palo verde and Texas ebony trees that are about 6 months old since germinating. I have read some mentions about tap roots. I know the mesquite trees tend to have a very deep tap root in nature. I am wondering if I should be concerned with these tap roots while they are young or if I can wait until they get some size on them. They are container grown at the moment and will be for many years since I lack the space to put them in the ground. Should the tap root be cut or have a tourniquet applied to them at this young an age or should I be waiting for a particular stage in their growth?
The mesquite and palo verde trees are approximately 18" (45 cm) tall and the Texas ebony are around 8-10" (20-25cm) tall at the moment. They have only been in a small 1/2 gallon (2 liter) pot but will be transferred to a 15 gallon (56 liter) pot soon.
I understand these trees will take many years to grow into anything worth trying to develop. I enjoy growing stuff in general and will use the info I obtain while growing these young trees to help make sure I am capable of caring for these trees properly some day when I am old and gray. I appreciate any advice.

Thank you,

I guess you have sown them indoors? For now your focus should be to keep them aluve until they have gone thrue their first winter. Temperate and subtropical trees sown indoors in the end of season will have more than 1 year until first dormancy period. Many trees gets very stressed by that and some will die from it.

I would not cut tap roots until one year from now. But It can be done much later. I primarily do bonsai from garden center materials 5-10 years old. They all have the taproot still and it is no issue whatsoever to remove it by then. I also have a yamadory pine about 40 years old which I cut the taproot on the day of colecting that are doing fine.

Thank you. Where I live we have relatively mild winters rarely falling below 35f (2c), but yes I did sow these seeds in a greenhouse. i was so concerned on how I was planning on keeping everything alive through our brutal summers I didn't realize that next winter could be an issue. I appreciate your response and will wait and see what these guys all look like about a year from now once they have had an entire year outdoors.

Just out of curiousity. What was the temperature when they germinated?

Tropfrog wrote:

I would not cut tap roots until one year from now. But It can be done much later. I primarily do bonsai from garden center materials 5-10 years old. They all have the taproot still and it is no issue whatsoever to remove it by then. I also have a yamadory pine about 40 years old which I cut the taproot on the day of colecting that are doing fine.

I will disagree. The taproot is the tree searching for water. You water every day or so so thr tree doesn't need that. The taproot will grow and grow, lifting the tree out of the pot and you don’t want that. What you want is lots of small feeder roots, which you will get by cutting the taproot off.

Tropfrog wrote:

Just out of curiousity. What was the temperature when they germinated?

All of the seeds germinated last August/September in my greenhouse at a temp of around 85f (29C). My greenhouse is also used as a house for my African leopard tortoises so it needs to stay unusually warm.
The seedlings have been outside in the yard for a month or 2 now. I started to bring them out once the low temps were no longer below 40f (4C), but I did occasionally move them back in for a day or 2 if we had a cold snap just to protect them. Our nights right now are in the mid to upper 40's (7-9c) and our day temps are in the low to mid 60's (16-18C). It doesn't usually get a lot colder than that here to begin with.

Ivan Mann wrote:

Tropfrog wrote:

I would not cut tap roots until one year from now. But It can be done much later. I primarily do bonsai from garden center materials 5-10 years old. They all have the taproot still and it is no issue whatsoever to remove it by then. I also have a yamadory pine about 40 years old which I cut the taproot on the day of colecting that are doing fine.

I will disagree. The taproot is the tree searching for water. You water every day or so so thr tree doesn't need that. The taproot will grow and grow, lifting the tree out of the pot and you don’t want that. What you want is lots of small feeder roots, which you will get by cutting the taproot off.

Thank you for taking the time to reply. Would you suggest that I remove the tap root now? Again, these trees will be kept in 15 gallon pots for some time. Would the tap root help this tree to grow bigger faster than the tree would if I were to remove it?
I am considering an experiment. Since I have multiples of each tree seedling maybe I should remove one's tap root and compare growth over the next 3-5 years and see how it was affected? I'm sure this has been done a million times, I just can't seem to find the posted results lol.

Ivan Mann wrote:

I will disagree. The taproot is the tree searching for water. You water every day or so so thr tree doesn't need that. The taproot will grow and grow, lifting the tree out of the pot and you don’t want that. What you want is lots of small feeder roots, which you will get by cutting the taproot off.

And I totally agree .

Yes, one definetely need to cut the taproot before it is placed in a shallow bonsai pot watered every day. Bigger containers do not need daily watering, not even weekly in my conditions.

Yes, one definetely want fine fibre roots before it is put in a shallow pot and that is achieved by cutting the taproot.

The question was now or later. Too me it is not an urgent task and it adds stress on top of the possible stress caused by germinating out of season. I just advice precaution as I do not think it is urgent. Health goes first.