Planting rhododendrons in 4 easy steps
How to plant rhododendrons and azaleas
Planting rhododendrons is not difficult at all, but there are a few things that are important to consider. You'll need to find a suitable location for this shade-loving plant and choose the best time to plant a rhododendron. Last but not least, the way you plant the rhododendron is also important. Here we'll go through all the necessary aspects of planting these amazing plants.
When to plant rhododendrons
You can plant rhododendrons at any time of year besides winter, but the best time to plant rhododendrons and azaleas is spring, when there is no longer danger of frost in your climate.
How to plant rhododendrons
1. Dig a planting hole twice as big as the rhododendron’s root system
2. Add acidic, well-drained soil that is half organic matter to the planting hole
3. Place the plant into the hole and cover with substrate, keeping the top of the root system a bit above the ground level .
4.Tamp down thoroughly and Water generously. Continue watering regularly after the top layer of soil dries out.
Where to plant rhododendrons
A semi-shady site, ideally under trees, with plenty of moisture is ideal for rhododendrons and azaleas. They can tolerate direct sun for a few hours, and species with smaller leaves (e.g. azaleas) tolerate the sun better. A site in full shade, however, will cause rhododendrons to flower less or not to flower at all.
The shallow root system of rhododendrons prefers moist but not waterlogged soils. Heavy clay soils are therefore not suitable for rhododendrons. Even if you fill your planting hole with a well-drained substrate, excess moisture will still reach the roots. If you have heavy clay soil, it is advisable to plant the rhododendrons on mounds (raised areas) so that the excess water can drain away. Soil drainage can also be increased by putting a layer of sand at the bottom of the planting hole to help drain away excess water.
Because of their acidic soil needs, neither rhododendrons nor azaleas should be planted near concrete walls or pavements, as concrete increases the alkalinity of the soil over time.
Soil for rhododendrons
The best soil for rhododendrons should be at least half organic matter (immature compost, peat, dry leaves, pine bark) and be well-drained, as rhododendrons and azaleas need oxygen for healthy root growth. Decomposing pine bark is a good choice for aerating the soil, which also prevents fungal root diseases. Rhododendrons prefer acidic soil with a pH between 4.5 and 6, so you can also use specialized rhododendron substrates with high organic content and a low pH, which are available in every garden center, or you can make your own 1:1 mix of peat moss and compost amended with pieces of bark, needles, dry leaves or other organic material.
Rhododendron planting tips
• If you have heavy soil that doesn't drain well, you can improve drainage by putting a layer of sand at the bottom of the planting hole.
• When planting, it is important that the top of the root system is not below ground level, and ideally it should be about half an inch above the ground.
• The planting hole should be twice as wide and deep as the size of the root ball. The plants should be watered thoroughly before and after planting.
• Rhododendrons and azaleas are usually sold in containers or with root balls. Potted plants need to be removed from the container before planting and the root system should be loosened and lightly trimmed in order to avoid rootbounding.