rhododendron, feeding roses & repot tree

Question

Hi!
Q1, Rhododendron has brown crispy edges on some leaves that crack off , it shows ? white underneath before turning brown, what is this & how do I treat it? I have the miracle grow powder, how much do I mix with how much water? I am scared of poisoning the plant which I have re-potted & it is in a more sheltered area than before the re-potting.
Q2, Shall I feed the rose bushes which are starting to show leaves, they are in pots, I changed the the top compost layer but not the entire pot.
Q3, I would like to re-pot an small evergreen tree to a smarter pot, as we are now in spring & it appears to be waking up , is it okay to move it?
Thank you.

Answer 1

I think the leaf damage is most likely environmental or sun scorch from winter.
The damaged leaves and branches can be pruned from the plant.
Here is some links with more information.

https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/rhododendron-care.htm
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/issues-with-rhododendrons.htm
https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/how-to-fertilize-rhododendrons.htm

Here are some articles to help with Rose care and fertilizer.

https://www.gardeningknowhow.com/ornamental/flowers/roses/rose-fertilizer.htm
https://www.gardeningknowhow.com/ornamental/flowers/roses/best-rose-fertilizer.htm

I would go ahead and repot the Evergreen now. Make sure not to use to large of a container. Just large enough to allow new growth.
Use good quality potting soil and make sure the container has adequate drainage.