A good container mix for rhododendrons is half ProMix or other peat based potting mix and half soft wood bark mulch. I think there is a prepared mix like this, but I've never seen it available in retail centers. The Lowes' soil for acid plants is probably peat based and should be fine. All peat based mixes break down and grow more compacted with time, so replanting into new mixture will be necessary every 3 years or so. This is easy to do, however. Olga Mezitt is often listed as a semi dwarf variety, but it's certainly capable of growing to 6 feet in time. There are other more dwarf varieties that might be more suitable for a container. Also, Olga Mezitt is a very hardy rhododendron, but will be much less so in a container - the small volume of soil in a container will freeze much more deeply then the ground so winter protection will be needed.

For really good plant survival in a pot,the usual rule of thumb is to plant a variety that is hardy 2 zones colder than you are unless you want to do the work needed to insulate or protect your plant.

I purchased a beautiful azalea (rhododendron hybrid)in Feb. It's in full bloom & healthy. It's in dire need of transplanting & confused about the best potting soil to use. I want to keep it in my house in larger container. I have an organic potting mix which contains fir bark, forest humas, peat moss, perlite, chicken manure, worm castings, bat guano, kelp meal, alfalfa meal, oyster shell & dolomite limes (ph adjusters). What do you think? I've also heard myricle grow works as well. My phone # is 530-432-7685. I live in Grass valley ca., 95946, don't know zone.
thank you, Peggie

Can you tell how acidic is this mix? Azaleas prefer acidic soils (around 5-6) and will tolerate (up to a point) some neutral/alkaline soils. I am just wondering because you listed dolomite lime pH adjusters. Lowering acidity is not what you want to do with azaleas and rhodies.

Hi Peggie,

You will be better off if you get a product that is especially for acid loving plants such as rhododendrons and azaleas. The mix you mention sounds like it is too fertile. Azaleas have low requirements for fertilizer and if given too much will look lovely but not bloom. Make sure the new pot has drain holes. Drainage is the key to growing azaleas. It is best to use two pots. The inside pot has the drain holes with stone in the bottom to provide excellent drainage. The outside pot is decorative and catches the water that comes out of the inside pot. The inside pot must be sitting on something to raise it so that it won't be sitting in water caught by the outside pot.

Here is a link that might be useful: How to care for rhododendrons and azaleas.

PS: Luis had good points about the acidity. Acidity is essential. In some areas with deep wells, the water is alkaline and this can lead to decline of azaleas. In that case it is best to use rain water.

You mentioned Miracle Grow (Miracid). I would avoid the liquid form like the plague. First, it builds up salts in the soil which is what potted plants don't need. Second, it is rich in nitrogen, which is what azaleas don't need too much of if you want to have flowers.

The Miracle Grow powdered azalea fertilizer is OK if used sparingly. Even better is HollyTone. If used at all, use at half the amount recommended on the package.

Keep the azalea soil moist but don't water until the soil begins to dry out. Too much water and poor drainage is the chief killer of azaleas. Soil that is not acidic leads to slow decline.

The location is important. They need some sun to set buds for the next season. My experience is that azaleas are good greenhouse plants, in that many varieties can be forced into bloom. But most are difficult house plants. They typically should bloom in the spring, be exposed to partial sun in the summer so they form new flower buds for the next season. Be kept cool in the fall and winter. Then when the days get longer in the spring they will bloom again. The bloom only lasts for 2 to 4 weeks each year, so don't expect the plant to keep on blooming. There are some azaleas under the Encore brandname that bloom all summer. I have no idea if they make good house plants or not.

Your hardiness zone is 7B which is good for most hardy azaleas, but not for many florist/greenhouse azaleas which can't tolerate freezing.

Good Luck!