Rhododendron looking very poorly

[siliconglen]

Hi
Over 20 years ago I was given a Rhododendron in a pot which did quite well in the pot, flowering really consistently but was ultimately only growing to about 5 feet tall due to the limitations of being in a pot. A couple of years ago our gardener transplanted it from the pot, including the soil in the pot and for the first few years it did OK in the garden but the last few years it's looked extremely poorly indeed. It doesn't get much direct sun but is in a similar place in the garden to the pot where it did OK. It's on the north side of a fence. It would be a pity to lose the plant completely as it's got sentimental value. Based in Edinburgh. Pictures taken a week ago.

thanks
Craig

 

[NewLeafTX]

My guess is that removing it from the pot changed the pH of the soil, in a way that the plant did not like.

Rhododendrons and their close cousins azaleas (see my avatar) both want a soil pH of 4.5 to 5.5.

If the surrounding soil in which the rhodo is planted has a higher pH than 4.5 to 5.5, this will cause the plant to become ill.

I recommend doing a pH test on the soil at the rhodo root ball, and another pH test on the garden soil about 8" away from the root ball.

If your soil turns out to be insufficiently acidic, you could buy soil acidifiers, and/or you could dig the rhodo back up, remove soil around its roots and replant it in a large pot with azalea soil.

In nature, rhodos and azaleas grow underneath pine trees because the needles that fall every year naturally acidify the forest soil when they break down.

 

[Esther Knapicius]

They like an acidic environment. I have a whole big Rhodo circle, about 5 large guys, been there going on 40 years, that is one garden I do not rake out the leaves from ever. I never have to mulch either. I just go in and if I see some weeds, pull them, that is about it.