Soil for Rhododendron

kompik

I've got a Rosebud Azalea (rhododendron X 'rosebud') that supposedly need lime-free acidic soil. What should I use?

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jjeter

Kanuma is what the Japanese use for azaleas. It has a natural 5.5 to 6 pH. I have about 10 azaleas planted in straight Kanuma. It is fast draining (you need to screen out the fines of course). It breaks down somewhat fast and you will need to repot about every other year. Akadama is also acidic. One of our club members works at the botanical garden and sent a sample of Akadama in for analysis. I don't have the complete analysis, but I remember the pH was in the 6 to 6.5 range which is also good for azaleas and most other bonsai. Both are a little expensive (they are shipped from Japan). If you don't want to go with a straight Kanuma of Akadama, a mix with pumice, lava, etc. are good. Leave out the organic material. Azaleas like moist, but not wet feet. Biggest problem I have is overwatering. The Kanuma holds a great amount of water anyway.


Hope the helps

Jeff

kompik

Thanks for the info. I've heard that you can use normal bonsai soil then just apply acidic fertilizers, but I have no idea how effective that would be.

kompik

Jeff, if I was to get my hands on some Kanuma or Akadama, would I pot my azalea in it as-is, or would I need to treat it like an organic soil component and mix it with lava rock or turface?

BonsaiGreenhorn

As-is. Akadama and Kanuma are mined from areas in Japan I believe. Its good to go.

I've kanuma on its way for my azalea. And Akadama, but for a few maples.

-Evan

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