50 to 75 percent is not too much, especially if you have heavy clay soil. This will promote the well-drained, acidic environment that azaleas love. Make your own mixture of humus, decomposing pine bark or pine straw, and peat moss, or purchase compost or soil conditioner to add to your native soil.
Morning sun with partial afternoon shade is ideal.
This allows their roots to become established before they bloom, and before enduring the stress of summer heat. You may also plant in spring after danger of frost has passed, or even during the winter if you live in milder regions where the soil does not freeze. However, spring is best for zone 6 and for zone 5, if conditions allow.
This is critical during the summer months of their first year in the ground. The soil should be moist but not soggy. Supplemental watering will depend on how hot it is and how much rain you receive. When you water, thoroughly soak the entire root ball. However, remember well-draining soil is essential. If the roots stay wet, they can rot.
To shape or to stimulate growth and flowering, prune your Encore azaleas immediately after their spring bloom. Pruning later in the year may result in loss of buds for your next bloom cycle.