Rhododendrons are beautiful shrubs, with gorgeous blooms, and there is a huge range of different varieties from the massive rhododendron sinogrande, which can reach 12 metres in height, to the tiny dwarf rhododendron fastigiatum ‘Blue Steel’, which only grows to about 12 inches.
Some have very large leaves which have a felt like brown covering on the underside, and some leaves are very small. There are some that are scented, and some that grow into quite big trees after a number of years. I expect most of us grow the smaller ones that will fit into our gardens, especially the yakushimanum hybrids (yaks), but whatever the sort you have, they all need a little care now and then.
Rhododendrons are acid lovers, they like well drained soil and a pH of 4.5 to 6, although there are a few rhododendrons that will grow in neutral soil. They like dappled shade and leaf mould or humus rich compost. It is possible to grow in a more open site, but they do need shelter from cold winds, and avoid frost pockets.
There have been some articles in the newspapers recently about the invasive variety, rhododendron ponticum, which has caused a lot of damage to habitats in parts of the highlands. It is probably best avoided in gardens, because there are much better varieties readily available in nurseries and garden centres.
Always hand weed around the roots, because rhododendrons are shallow rooted and could be damaged by hoeing; they like mulching with bark wood chips or leaf mould. Do not use uncomposted grass cutting, it can kill the roots. I use a fertilizer that is specially for acid plants and I water frequently in dry weather. If the bush is small, and it is possible, remove dead flower heads. There are some varieties that will hardly put on any new growth, simply because they are not dead headed. It is worth trying to do it; you could be rewarded with more flowers next year!