Propagation
Surface sow fresh seeds in boxes, using a sandy-peat media that is lime free and cover the seeds lightly with sphagnum or sand. Keep moist and pot up as soon as large enough to handle.

Semi hardwood tip cuttings that are taken from early to late summer from 25 mm (1 in) to 200 mm (7¾ in) long. All but the top leaves should be removed and they can be reduced by half to improve aeration and reduce evapotranspiration. Place the cuttings in a well-drained media and maintain a temperature of 21° C (70° F) and apply water misting on a regular basis. 

Cultivars may be grafted onto a rootstock.
Aerial or ground layering during the growing period.

Botanic information
Leaf: The leaves are elliptical to oblong up to 50 mm (2 in) wide with an obtuse apex that is mucronate. The leathery textured glabrous leaf is dark green above and light green below with a petiole up to 38 mm (1½ in) long. 

Flower: The broad campanulate to funnelform flowers are arranged in terminal umbel-like racemes (trusses). The flower colour varies from lilac-purple to lilac-rose and is occasionally white. They appear during late spring.

Fruit: The dehiscent woody capsule has 5-valves and contains numerous tiny seeds. The small seeds are viable but the plant is commonly reproduced vegetatively to maintain true to type.

Culture
Rhododendrons grow best in a sandy loam that is tending acidic and is well drained with a mixture of leaf mould and peat that is kept moist, and friable. They do not thrive in clay or limestone based soils with a high pH and is very sensitive to salinity. 

As they are shallow rooted they are easily transplanted with a good ball of soil kept around the roots. When replanting apply a thick layer of mulch which will retain the soil moisture, improve soil aeration and decrease the penetration of frosts in cold areas. 

When planting from a container you may make vertical slits down the root ball with a sharp knife to ensure contact with the new soil and the hole once planted it should not be allowed to dry out. 

The large leaf forms tolerate a shaded position, under deciduous trees or on the southern side of buildings and the smaller azaleas can tolerate a sunny position, but all forms require adequate light for flowering.  

Normally little pruning is required, but rhododendrons will tolerate cutting back if they become leggy or to rejuvenate.