Before planting ensure your site and soils meet the growing conditions needed for Rhododendrons. In most cases partial or half shade is desirable, in hot dry areas it is essential. Rhododendrons and azaleas prefer a porous well drained, acidic soil pH 4.5 – 6, but they can be grown in heavy soils if special precautions are taken. Find our more about site and soils.
Dig a planting hole 30cm wider each side of any plant rootball and 40cm deep, regardless of soil type. Mix one teacup of acid fertiliser with the soil that goes back into the hole. Always plant rhododendrons and azaleas so the soil level just covers the top of the rootball. After planting, mulching with coarse organic matter (not lawn clippings or mushroom compost) will help conserve moisture and provide a cool root run, at the same time controlling weeds. Find out more on planting.
Water carefully during dry weather especially during the first three summers after planting. It is better to wet the soil deeply each time and water less frequently. Under watering or severe dryness will show up as brown tips to leaves in the Autumn – Winter period. A water stressed plant is more susceptible to disease, insect attack and dieback.
- Avoid areas exposed to prevailing winds or drying coastal winds.
- Check basic soil pH – should be 4.5 – 6.
- Avoid planting into heavy clay soils – adjust as necessary – acid and friable is ideal (see our Cultural Hints re Gypsum.)
- In clay type soils we recommend adding Trichopel at planting time.
- Keep well watered in sandy or free draining soils.
- Mulching with bark chips, chopped up garden prunings or rotted leaf mould.
- Mist irrigate the foliage in the evening during extremely hot periods, along with normal watering practices.
- Plant lightly foliaged, deciduous trees for shade.
- Be prepared to spray for pests e.g. Thrips
Yellow leaves, wilting leaves or pests such as Thrips are all problems that can effect the overall health of your Rhododendron. See our plant health guide to help identify the problem and how best to control it.
Have another issue? See our Plant health FAQ's
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