Originating from Japan, Turkey and South America these garden ornamentals are happiest growing in acid soil, with a PH rating of 7 or below. If your plot is more on the alkaline, limey side don’t despair. It is possible to dig in leaf mould and ericaceous soil to boost the acidity, feed a plant with ericaceous liquid feed or failing that – grow Azaleas in pots, where you can tailor the compost to meet their every need.  Tempted to learn how to grow azaleas? Then discovering when to plant azaleas is the perfect starting point.

When to plant azaleas

Classified either as evergreen or deciduous azaleas, these long-lived plants need little attention once they get established – and they make for a stunning addition to your flower bed ideas. Do protect from late snowfall and frosts though, to prevent young shoots and buds from being damaged. Flowering from late spring through to mid-summer these shrubs are best planted during their dormant period.

 When is the best time to plant azaleas in a border

Azaleas are best planted during the fall, when the plants are dormant, but the soil is still warm. Late spring is also a good time, as it gives the plant an opportunity to establish its root system over the summer, before any cold weather arrives. Avoid planting altogether when the soil is frozen or waterlogged as this will severely damage the roots and, most likely, kill off the plant.  Choose a sheltered spot in dappled shade for the best results. ‘If you would like to grow your ericaceous plants straight into the soil but don’t have a suitable pH level in your garden naturally, dig out a large enough hole, line the edges with a sheet of plastic with drainage holes, and add a specialist ericaceous compost to plant them into,’ says Angharad James, product manager at Phostrogen.

 When is it best to plant an Azalea in a pot 

Late spring and early fall is a great time to establish a nursery grown Azalea in a new container. ‘Make sure to choose a container with a drainage hole(s) at the bottom, and one that is large enough to allow for 2 to 3 years of growth before shifting your azalea up to a larger size container,’ say the team at Wilson Bros Gardens (opens in new tab), Georgia. ‘This might mean your planting pot would be 6 inches (15cm) or more, wider than the root ball of your plant.’  Azaleas are shallow rooted and wide spreading, consequently they prefer their root ball to be just below the soil’s surface. Aim to sit the root ball an inch below the top of the pot and fill around the edges with ericaceous compost, firming lightly.  ‘The next step is to put a layer of 4-5cm of pine bark chips on top to finish off the pot,’ says Will Murch of azalea experts, Osberton Nurseries (opens in new tab). ‘As well as looking really smart they keep the roots cool, aerate the soil, keep moisture in and stop weeds from growing. it is important to pull these 2 or 3cm away from the point where the plant’s stem joins the compost to stop it getting too moist.’