How to sort out nursery pine roots?

[Manbris]

Hi!

Sadly one of my dwarf scots pine dead this year after repotting. I may have killed it - was probably too dry and the pond basket was a bit wobbly so should have tied it.

It was in organic soil I changed it to lava rock, pine bark and a bit compost and its old soil in spring- with the hope to strength the roots. The tree was very strong last year. However It did not grow new roots in the new mix from the bottom of the tree, only tried to grow new roots from the surface. This makes me wonder soundness of the approach, if the tree is happy and I cannot water the tree once a day then I might be better off just use organic soil with added perlite to grow it while sorting out the root structure instead of all inorganic soil? As the roots will not be ready for a bonsai pot for years and years and the top needs sorting out.

It is funny I thought I had a straight trunk but after removing all soils. I see there is movement buried in the lower part of the root ball. These are grown in the ground and then dug up and sold to nurseries. And will just up-pot the tree without any root work. The consequence is we have layers of roots and they are all circulating in the can.

The last two pics show the issue. My question is how do we go about sorting the roots out in this case? Half root ball may work but also has a risk of losing large trees. Do we grow top surface roots and then remove bottom roots gradually or the other way around? In this case if I want to use the deeper base, I may not have enough roots at deeper end, how would you go about it?

Thanks!

 

[Potawatomi13]

You seemed to have plenty of roots and could have just sawed off bottom half or nearly so and trimmed circling roots repotting with soil with similar draining charachteristics to what was removed if it was any decent potting mix. I have done this several times successfully(always)when it was too cumbersome to clean out the old soil. You may have bare rooted too much for the trees survival or possibly bad watering.

 

[Brian Van Fleet]

3 things I’d do differently in this case:

1. I really don’t want to bare-root a pine.

2. I always tie trees down in the pot to immobilize the roots.

3. I am anti-pond basket as a grow-out container, terra cotta containers are far superior, as are Anderson Flats. I don’t want the sides of root masses to dry out and die, they need to grow, so the entire premise of the basket is flawed in my view.

Your question on sorting out the roots from a nursery container: saw the bottom 1/3 to 1/2 of the roots off, then rake out one side of the remaining roots (front half or back half, for example). Make those roots radiate outward from the trunk, then tie it down into a sturdy container and work in good soil very well. Boon students call this HBR, half bare-root. The next time you repot, replace the other half of the original soil, while not touching the half you already removed the OG soil from.

 

[KateM]

I think bare root was done post mortem just to show the structure...

 

[Manbris]

3 things I’d do differently in this case:

1. I really don’t want to bare-root a pine.

2. I always tie trees down in the pot to immobilize the roots.

3. I am anti-pond basket as a grow-out container, terra cotta containers are far superior, as are Anderson Flats. I don’t want the sides of root masses to dry out and die, they need to grow, so the entire premise of the basket is flawed in my view.

Your question on sorting out the roots from a nursery container: saw the bottom 1/3 to 1/2 of the roots off, then rake out one side of the remaining roots (front half or back half, for example). Make those roots radiate outward from the trunk, then tie it down into a sturdy container and work in good soil very well. Boon students call this HBR, half bare-root. The next time you repot, replace the other half of the original soil, while not touching the half you already removed the OG soil from.

Thanks a lot - will keep these in mind next time.

If we would like to use deeper roots as future nebari, for example the green line shown in the pic and current roots are shown in red line, how would you go about it?

 

[Manbris]

You seemed to have plenty of roots and could have just sawed off bottom half or nearly so and trimmed circling roots repotting with soil with similar draining charachteristics to what was removed if it was any decent potting mix. I have done this several times successfully(always)when it was too cumbersome to clean out the old soil. You may have bare rooted too much for the trees survival or possibly bad watering.

You are right- I did 7 pines this spring 2 did not make it. For this one - although strong, was repotted last year for sale before I got it. So the roots were disturbed again. Watering was bad - I left the top too dry and it was in the hottest spot in my garden. The choice of pot was bad for this tree.

How do you judge how much roots is enough for pines?

 

[Brian Van Fleet]

Thanks a lot - will keep these in mind next time.

If we would like to use deeper roots as future nebari, for example the green line shown in the pic and current roots are shown in red line, how would you go about it?

Just remove a few roots from the trunk and lower the soil level until you get down to the green line. It might take a few repots.