Rhododendrons: Moving large Rhodo.

We have collected many Rhodo's over the years (since 1990). Some of them becoming too close together and we where going to dig them up and either replant or find homes for them.
They have all done very well, but our favorite ones are going to be overgrown by the other and will reduce the amount of flowers we will get.
Any thoughts from past experience would be appreciated.

 

Dense, shallow fibrous roots easy to handle. Slice around them and replant where wanted. A good project for damp, mild spells during fall and winter.

 

We used to sell large ones when I was growing up. Take a good ball of roots and replant or in our case they were put into sacking (burlap?) till moved on. Some of the big ones were prepared for lifting by digging a trench around them several weeks before they had to be lifted. We have just done a large camillia here and the person thet gave it to us also pruned it back by a third. Seems to be working droopy leaves back to normal. We have had mild weather and really good rain which has helped.

Liz

 

Thank you Liz,
It is always good to here from someone that has first hand experience with moving large shrubs. I went a bit crazy when I join the local Rhodo Club back in 1990. Started with alot of Hybrids, then went on some tours and the foliage of some of the species Rhodo's got me realy interested. Went out and bought about ten. We had, had a Rhodo Conference in our area and the one of the local nurseries brought in alot of harder to find species.
Enough rambling
Again, thank you

 

Neither root pruning in advance of transplanting nor top pruning at planting time have been shown to be of benefit in organized investigations. Root pruning of tree and shrub transplants might work if the new roots grown afterward were not cut off when the plant was lifted later - later being long enough for a substantial amount of new roots to grow - something that for most of the year does not happen in a matter of weeks.

Arbitrary top pruning at transplanting has in addition been seen to be not just unhelpful but harmful. Plants are integrated systems, like us. Amputation of one part of the plant body has deleterious effects on the remainder. Practitioners of bonsai have long used pruning of roots to reduce top growth, help maintain the specimens in their care in a miniature state. Growth of new roots is supported by leaf and stem tissue, and vice versa. The less of one a transplant comes away with, the less of the other it produces after transplanting. The condition of a plant prior to planting has a critical effect on how readily and well it establishes in the new site.

 

Ron I think the trench thing was done so that these very large rhodos could adjust to being moved. They were small trees in many cases. Yes it's important to get a good root ball and have the new area ready so the trauma is kept down.

Liz

 

The common concept is that new roots will form in response to root pruning undertaken well in advance to the final digging and moving and that this will confer an advantage. Otherwise it would appear there is no other useful adjustment the shrub would make while sitting there with a trench around it.

Most growth of new roots occurs in spring, in response to hormones produced by the opening vegetative buds that have overwintered at the ends of the shoots. At this time of the year (fall) existing, intact roots will be elongating - the most of the whole year. The rest of the time the roots are comparatively inactive, other parts of the plant receiving energy allocation priority. Depending on what time of the year you do it, when you prune roots it may be months before a major flush of new root growth occurs. The tradition seems to be to prune roots one year before transplanting.

Done now, followed by lifting less than a month later it would be expected to merely cut off the elongating existing roots, expose the specimen to whatever other adversities might occur as a result of there being a zone of air (trench) around the rootball for some weeks.

 

I am happy to accept explanation. I can not remember what time of the year etc. I know it was done with young trees too. May be it was to get them to a certainn stage of dug up so that the whole thing would be done quickly and easily on day they were needed. These were hand dug no machinery then.

Liz

 

For more background look at libraries of colleges with hort. departments for the plant growth and production titles listed here. Do not know how much presence these have outside of the US.

http://www.lacebarkinc.com/books.htm

Author is a trailblazing methodology investigator and inventor.