All azaleas grow very well in pots but there are several considerations to be aware when choosing the best pot for planting your azaleas.
Each consideration will make a difference to how well you azalea grows and flowers.
The best pot for azaleas is made of clay, ceramic or terracotta as they keep roots cool in summer compared to plastic or metal pots. Azalea pots must have drainage holes in the base allowing water to escape. A 16 inch diameter ensures pots contain enough soil for insulation and holds enough moisture.
Good Drainage at the Base of the Pot or Container
By far the most important characteristic of a pot for azaleas is that it must have drainage holes in the base. Otherwise the pot will collect water and the roots will be saturated. Azaleas require moist soil but saturated or boggy soil will quickly lead to the fungal disease root rot.
It is also a good idea to use a 1 inch layer of gravel at the bottom of the pot before adding the soil and planting the azalea. This will allow for the drainage holes to be kept clear from compacted soil or any thing else that may hinder the flow of excess water out the bottom of the pot.
Of course the right potting mix for azaleas is important to ensure that azalea roots have the optimal balance of moist soil that is also well draining. Read my article on the best potting mix for azaleas for best practices.
If your pot is outdoors then it is a good idea to position the pot or container on ‘feet’ which elevate the pot slightly off the ground. Sometimes when pots are placed on patios, water drain out the bottom of the pot and pool on a patio slab which in turn can make the soil too boggy for azaleas.
If the pot is elevated off the ground then water will escape efficiently and the azalea will remain healthy and free of the fungal disease root rot (plyothera) which is one of the most common azalea diseases. If your potted azalea looks unwell read my article on common problems for potted azaleas.
Avoid this mistake!
A very common mistake with potted plants is to use a drip dray underneath the pot to catch any water that trickles out the base, particularly with indoor pots.
This will catch all the water draining out of the pot and have the same affect as a pot without drainage holes. The soil quickly becomes saturated and the azalea starts to show symptoms of root rot.
With indoor pots I would recommend that you take your azalea either outside temporarily or place it in the sink for 30 minutes after watering to stop water trickling out of the pot and damaging furniture or onto window sills. For more tips on watering read my guide on how much and how often to water azaleas.
Best Pot Size For Growing Azaleas
Azaleas are fairly shallow rooted plants which means they are susceptible to drought in hot weather or because of infrequent watering.
Therefore a bigger pot for outdoor azaleas is preferred as larger pots have a greater capacity for soil. The more soil in a pot the more moisture can be conserved which reduces the risk of drought, as pots can dry quite quickly anyway.
More soil also provides more insulation for the roots from the cold which can increase an azaleas resistance to the worst of the Winter weather and more access to nutrients for the roots.
I personally see outdoor azaleas grow best in pots that are 16 inches across or more. This gives the azaleas shallow roots enough space to spread out to access water and nutrients.
Azaleas actually don’t mind being somewhat pot bound as long as they are watered frequently and have an application of fertilizer in the Spring. Fertilizing azaleas in pots is important to ensure healthy foliage and a strong display of flowers in the Spring/Summer. Read my article for more about when and how to fertilize azaleas in pots and containers.
The size of the pot will ultimately restrict the root growth and size of the azalea. For indoor pots where cold weather is less of a concern, azaleas can be planted in more modest pots, particularly if you are cultivated azaleas as subjects of bonsai (azaleas are a great choice of species for growing resilient bonsai trees).
Best Material for Potted Azaleas
Another consideration is the type of material your pot is made of. Which is best out of plastic, metal, wood, ceramic or clay?
Azaleas can be grown in pots and containers of almost any material although some are better then others.
I personally recommend avoiding metal and plastic pots for growing azaleas and rhododendrons. Metal is a good conductor of heat and therefore heats up very quickly in the sunshine.
If the pot heats up then this will increase the rate of soil evaporation and increase the likelyhood of drought and potentially increase the chance of the roots developing the fungal disease root rot as warm soil is one of the conditions that promotes disease.
With metal pots you may have to increase the frequency of watering in hotter weather which is inconvenient as azaleas characteristically require moist soil and cool roots and will be on the first plants in the garden to wilt because of drought.
Plastic pots are often okay for growing azaleas as long as the pot has plenty of drainage holes and the plastic is not too thin as a thicker pot helps to keep the soil and roots cooler in hot weather. Plastic does however tend to be less breathable for azalea roots for respiration.
Ceramic, terracotta or clay pots are always the best for growing azaleas. A thick clay pot will stop the sun from heating up the soil as much and protect the azaleas shallow root system from drought. A thicker pot also helps to protect the azaleas roots in the Winter.
Clay pots also tend to be more breathable which helps the respiration of azalea roots.
Wooden pots and containers can also work well as they are good for conserving moisture. However azaleas require consistently moist soil which causes the wood to rot so you may need to replace the pot after a few years, hence why clay, terracotta or ceramic pots are a much better option for growing azaleas.
- A pot that is 16 inches in diameter is the ideal size for growing azaleas. This ensures the pot contains enough soil for insulation in the winter and holds enough moisture for the shallow roots.
- The best material for potted azaleas is either clay, ceramic or terracotta as they doe not heat up quickly in the sun whereas metal and plastic pots conduct heat efficiently which dries out the soil and causes drought.
- The most important characteristic of a pot for azaleas is that it has a drainage hole in the base so the soil does not become saturated. A layer of gravel at the base of the pot will prevent blockage of the drainage holes with compact soil so that excess water escapes efficiently out the bottom of the pot.