In general, azaleas in the landscape require little or no fertilizer. Having humus (decomposed organic matter) in the soil and maintaining an organic mulch around azaleas are more important than applying chemical fertilizers, and much safer. Decomposition of the mulch normally provides the nutrients needed for the good health of the azaleas.

If chlorosis of the leaves (yellowed, with green veins) or stunted plant growth suggest there may be nutritional deficiencies, a soil test may be useful. This can usually be arranged through your county agent at little or no cost. Soil test results will show the specific amounts of nitrogen, phosphorus, potassium and various other important elements that are present in the soil. The results may be accompanied by specific fertilizer recommendations to correct any deficiences. If not, your county agent may be able to provide specific recommendations.

Applying chemical fertilizers without knowledge of any deficiences in your soil may not help much, and may actually harm your azaleas. As a very general rule, more azaleas are killed by kindness than by neglect.

Azaleas need very little fertilizer. The only things I put around mine is cottonseed meal and garden sulfur.

we planted azaleas about 3 months ago and they are now wilted and look like they need watering. WATERING DID NOT DO ANY GOOD. WHAT I DO?

Usually plants die from poor cultural conditions. The main requirements for azaleas are drainage, adequate moisture (no more), acidic soil, a good mulch to keep the roots cool, and partial shade.

Azaleas planed too deeply in clay soil without opening up the roots and soaking the root ball before planting will die a most certain death whether you have sun or shade.

I recommend digging them up, opening up the roots, soaking the root ball, and then replanting.

When you buy plants, the root balls are usually root bound. They need to be opened up. I usually take a box cutter and cut the root ball down from top to bottom about 5 or 6 places around the outside. Then I pull loose roots wadded up on the bottom. Then take a claw tool and pull out the roots so they are coming out from the root ball.

Then soak the root ball about an hour before planting. A dry root ball never accepts water if you plant it. It will always be too dry.

When replanting, make sure the soil is acidic. You can mix conifer bark dust or peat moss into the soil before planting. Plant higher than it was in the pot when you bought it, never lower. If the soil is poorly drained, make a mound a plant the azalea higher than the surrounding soil. After planting mulch, about 2 " of conifer bark pieces or similar material.

Here is a link that might be useful: How to grow rhododendrons and azaleas.