Fix a Severely Root Bound Rhododendron planted over 10 years ago

mrcreosote

13 days ago

last modified: 9 days ago

This plant appears healthy but stays at about 3' (EDIT: actually 4') tall while others are 8-10' tall.

If I can "fix" the roots, will the plant begin to grow big like a healthy rhodo?

Some thoughts how to fix:

work on one quadrant at a time, perhaps one per year to minimize trauma?
Radial Cuts: cut radial slices through the soil? (I have a 16" long Sawzall blade)
Completely remove a small "pie slice" from the root ball?
Severly cut back the roots that are shallow leaving at least 2/3rds of the bound remaining to reduce trauma - perhaps the the shallow would grow vigorously and eventually become the primary roots for the plant?

Featured Answer

kevin9408

12 days ago

last modified: 12 days ago

Give the plant stem some good tugs and wiggles to see if it's still root bound. It will feel loose and only the area above the original hole will move. I've pulled root bound trees and shrubs out of the ground two years later to find the root ball was nearly the same as when it went in, lack of growth was the first sign. I've also noticed a root bound plant will dry out and wilt needing frequent watering compared to plants not root bound.

In these cases I would lift the plant/tree/shrub out and use the hose sprayer to blow out the original dirt and tease the roots loose and replant using the water hose to turn added soil to a soup to refill voids in the roots You don't want air pockets I've heard.

Disclaimer. None of what I said has been verified by me and it's only based on what I have done and may be unacceptable to others or even dead wrong.

Sort by:Oldest

Comments (8)

gardengal48 (PNW Z8/9)
13 days ago
Do you know if your rhododendron cultivar is supposed to grow to 8-10'? There are many dwarf rhodies that will stay very compact - 3-4' or less. Unless you can confirm what kind you have, I wouldn't be messing about trying to correct some sort of root defect that may or may not exist,

btw, rhodies are by nature extremely shallowly rooted.
mrcreosote
Original Author
13 days ago
No, this was definitely a large plant. It was gigantic in it's pot. As time passed, the size of the flowers and leaves started to decrease.

I have the cultivated and also the wild. it was so root bound it was solid white roots when I took it out of the pot. Back then I didn't know what to do. It's very frustrating because it was the biggest plant I ever bot and a good price.

(I just bot what appears to be a dwarf - it's a completely different type of plant. I have a row of privet hedges that are over 50 years old and this last year, two of them died - the very 1st deaths. I plane to "pepper" that row with a bunch of different plants. Also have a nice azelia that matches the color of my current Rhodi's. Also on the lookout for the Rose of Sharon.)
Related Discussions
Umbrella plant, SEVERELY root bound! Help!
Q
Comments (9)
I also "inheritted" a schefflera (I am assuming this is what you mean by umbrella plant). Mine is schefflera arboricola, not variegated. The plant was severely root bound, was in the same pot for 10 years. In the spring 3 years ago, i repotted it. What i did was prune a lot of the outer roots off and teased the soil a lot to loosen up the tightly wound roots. I tried replacing as much soil as i could. I had some leaf drop afterwards, but this could also be because it was trying to become acclimated to my home. The following year i also severely pruned it because it was leggy, it responded pretty well. I plan on pruning it even further to make it more compact. I think this plant can handle a wide range of stress and responds nicely to repotting and root/trunk pruning. The plant was about 6' tall and 7' wide at first, it is now 5' tall and 4' wide, going to make it 3'x3' or 4'x4' when i prune soon.
...See More
I Planted a Mimosa/Silk Tree 4 Years ago in NE Ohio Help!!!
Q
Comments (81)
Krycek1984, I want to address a few points brought up in your post. First, there's really need for more personal attacks. There were enough of those already in this thread. While I sometimes disagree with iforgotitsonevermind, she certainly isn't generally ignorant, and even when she and I see things in almost totally opposite ways, I don't think she tries to be arrogant. Maybe she gets a little over excited, but don't well all. Iforgotitsonevermind's concern was not whether mimosa is currently considered an invasive pest in the area, but whether it had the potential to be in the near future. Your assurance that it "will not become an invasive species unless global warming goes crazy", falls short of convincing me. As I said above, I'm not convinced that it will ever become a problem, but your assertion, that it's not even close, doesn't convince me the other way, either, and seems to be based more on feeling than proof. Your question about who cares if you plant Bradford pears can have many answers including a number of invasive plant groups (which are concerned about their damage to the environment in many areas), neighbors (who worry about the trees falling over the property line onto their car, producing a foul smell, or making the neighborhood ugly when they fall apart at an early age), and those that want to share information they've learned from their mistakes or observations.
...See More
Acidified the soil 10 years ago, is it still acid?
Q
Comments (13)
Lot of misinformation going on here....:-)) Acid planting mix can certainly help to achieve a proper degree of soil pH for some plants but it is unlikely to be a permanent condition if you use it in an inground planting situations - much more effective long-term if used in a raised bed or in a container situation. 8-10 years is a long time so I'd guess that current soil pH is no longer very acidic but you will not know for sure unless you test. And retail soil pH test kits are NOT worthless.....in fact, they are about the only accurate soil test kits there are on the retail market but you must use them with distilled (not tap) water. SoCal soils are often on the alkaline end of things but that is very different from sodic - if you have concerns about that then a professional soil test is advised. And finally, most plants are adaptable to a range of soil pH so that does not necessarily limit what you can plant in your existing soil conditions. Just avoid those that prefer the quite acidic conditions like the blueberries. Many fruit trees grow very well in SoCal soils so check and see what neighbors might be growing or what's sold at your local nursery.
...See More
Poor results with pot bound root pouches
Q
Comments (5)
Yes I typed "fiber" but it's fabric. How these work is the roots grow out through the fabric instead of being deflected by solid pot walls. Heavy root sections inside the container are expected. But circling roots are not - I'd look at the Carl E Whitcomb Lacebark Inc. web site to see what his current remarks are about using fabric containers. If it has any relevance to what you are seeing now I do know that some years ago there was a problem with a manufacturer not making fabric containers to designer specifications, resulting in crop failures.
...See More
iochroma
12 days ago
I consider a dense root ball perfectly normal for rhodys. Chopping away roots will not help growth.

Is there some barrier around or beneath the root area?

Have you been fertilizing this plant at all?

Have you considered top-dressing with compost several times a year?
mrcreosote
Original Author
12 days ago
It is root bound. When removed from pot, so root bound you could not see dirt was white with solid roots. I knew I should have researched it then, but just put it in the ground. I have fertilized it every few years. It is planted it regular soil. No composting. Nourishing it has no appreciable effect.
iochroma
12 days ago
No nutrients = no growth
Sherry8aNorthAL
12 days ago
Pop it out of the ground. Take a sharp knife and slice from top to bottom through the EDGE of the roots. Replant, making sure it is NOT deeper than it was to start. Take a garden fork and loosen the soil around the plant The roots are pot bound and keep going in a circle. .

LEAVE IT ALONE, except for water and mulch.
mrcreosote thanked Sherry8aNorthAL
davidrt28 (zone 7)
9 days ago
I had a similar problem once and killed the plant trying to unknot the roots. So be careful, certain varieties of rhododendron can have brittle roots that easily snap.

Fix a Severely Root Bound Rhododendron planted over 10 years ago

kevin9408

Comments (8)

gardengal48 (PNW Z8/9)

mrcreosote
Original Author

Related Discussions

iochroma

mrcreosote
Original Author

iochroma

Sherry8aNorthAL

davidrt28 (zone 7)

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Fix a Severely Root Bound Rhododendron planted over 10 years ago

kevin9408

Comments (8)

gardengal48 (PNW Z8/9)

mrcreosoteOriginal Author

Related Discussions

iochroma

mrcreosoteOriginal Author

iochroma

Sherry8aNorthAL

davidrt28 (zone 7)

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

mrcreosote
Original Author

mrcreosote
Original Author