When can I move my Rhody.? How big of a football should I expect on a 10yr.
You can move your rhody anytime of the year if they are handled correctly. Here is more:
A master gardener noticed that I have a problem with grubs eating my rhody and recommended a powder that begins with "di or dian". What is the full name?
Diatomaceous earth is a white powder used to control grubs:
https://www.gardeningknowhow.com/plant-problems/pests/insects/get-rid-of-grub-worms.htm
I have a pot grown rhododendron which is several years old. We are about to move house and I would like to reduce it's size and hopefully encourage good new growth for next year. Can pot phododendrons be hard pruned, and is this a good time of year to do it?
Pruning is seldom needed except for removal of the spent/faded flowers. One can prune out up to 1/3 of branches with flower buds. This will reduce the blooms in spring 2022, but the remaining branches will still provide plenty of bloom. There is normally little need for pruning azaleas and rhododendrons if you select a compact cultivar and an appropriately sized pot with rollers. If growth becomes excessive, reduce the size with light pruning. Plant form can be improved by pinching out the soft, new shoots of vigorous-growing plants. Rhododendrons and azaleas may be pruned to induce new growth. Prune out dead/diseased/damaged branches, and if the plant has become scraggly, start cutting the oldest branches back to encourage growth in younger branches. But normally, pruning in the fall is not recommended as it will remove the buds for newsprint 2022 flowers and stimulate regrowth that may not harden before winter and freeze back and die.
With large leaved rhododendrons (aka, elepidotes), you must prune just above growth joints. Each year as the plant starts to grow there is a visible point where the plant started growth. That spot is reffered to as a growth joint. Prune just above it, because that is where the dormant rhododendron growth buds are located. Don't prune between joints as there are no dormant growth buds in that area. With azaleas and small leafed rhododendrons (lepidotes), you can prune anywhere along the stem because these two plants have dormant growth buds just about nearly everywhere.
Can a Rhododendron be propagated from a cutting of an older established one?
Yes. The younger the growth, the better, so try and find newer growth if you can. Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/projects/rooting-plant-cuttings.htm
https://www.gardeningknowhow.com/garden-how-to/propagation/cuttings/what-are-root-cuttings.htm
https://www.gardeningknowhow.com/ornamental/shrubs/azalea/propagating-azalea-cuttings.htm
see enclosed photo
This can be due to environmental stress. This article should help:
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/brown-rhododendron-leaves.htm
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/fertilizing-rhododendrons.htm
My wife loves this plant but we want to move it to a more prominent area in our garden. Can this be done?
This is a type of Rhododendron. They do not move well, and will not do well in full sun. You would have to acquire a different shrub for your other area, since moving this one would likely kill it.
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron
ructions. When should I prune them back?
Usually if they have buds but don't bloom, a late frost nipped them. Rhododendrons should be pruned after they bloom to prevent cutting off the buds that formed last year (old wood).
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/rhododendron-care.htm
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/pruning-rhododendrons.htm