Azaleas are popular plants and can grow from Seattle to Southern California. They are not difficult to grow if properly selected and properly cared for.
Here are the proper steps to follow:
- Grow in peat moss fertilized with cottonseed meal, using 100 pounds of meal to one bale of peat.
- Light compost, sand, and oak leaf mold may be mixed with the peat in heavy soils.
- Cottonseed meal, the base of most acid fertilizers, is likely to form mold in the fog area. If this occurs, substitute fish emulsion.
- Keep plants moist but not wet.
- Water before and after feeding and never feed just before or during the flowering period.
- Propagate by using ripened wood cuttings in midsummer or by layering.
- Do not disturb the shallow roots when you cultivate.
Ideal Shade And Location For Growing
In Southern California, azaleas should be given some shade. A slope where live oaks grow is an ideal location for azaleas.
Do not plant them, however, under shallow-rooted trees such as acacias.
When tree roots smother azaleas, the plants must be lifted and reset with peat, sand, and fertilizer added to the soil.
Azaleas are popular in Southern California as pot and patio plants and for edging pools.
Fertilizer Application
If Colorado River water turns the foliage yellow, use an acid fertilizer to counteract its effect but do not overdo this.
Pulverized magnesium limestone also relieves alkaline water trouble.
Planting should be done in late fall, and through the winter, the plants set so that the soil around them is no higher than the root ball.
Feed after blooming with one of the special azalea fertilizers and repeat the application with 2 other feedings at six-week intervals. Follow package directions.
In the Northwest, give attention to good drainage. Avoid deep planting and never over water.
Ideal Light Conditions For Good Growth
Most azaleas will take full sun. In the sun, they flower profusely and need more food and water than those in semi-shade.
Deciduous azaleas do particularly well in the Northwest. Plant them when the danger of frost is past.
Pest Treatment
Thrips and red spiders bother in the Northwest, but you can help prevent this by washing the top and bottom of the foliage each morning.
Use a miticide for the red spider.
Feed the plants once after flowering and give one more feeding 6 weeks later.
Kurume And Indica Azalea Varieties
Kurume azaleas bloom more profusely than the indicas. This is because they have smaller flowers and are hardier.
Indicas make good pot plants and can be shaped by pinching. They form closely-knit bushes with dark foliage.
The Rutherfordiana hybrids become too large for the small garden.
Glenn Dale hybrids bloom almost continually in the fog area.
Know your colors and the plant’s ultimate size before assigning them a special location in your garden.
The following varieties were chosen for adaptability to the Southern California area and the Pacific Northwest, respectively.
The information included here does not apply to the specialized growing conditions in the San Joaquin and Sacramento Valleys.
Ideal Varieties For Southern California
For Southern California, try the following varieties of Kurume azaleas.
They are evergreen plants and form dense shapely specimens:
- Flamingo is a brilliant double coral
- Laughing Water has single, large white fragrant flowers, is fairly tall and large, and can stand Colorado River water
- Pale Moonlight has single, large orchid-like flowers of silvery lavender
For the indicas, try the following:
- Azalea Vervaeneana alba, an evergreen type, has double, large white flowers, blooms profusely for many months, and will stand Colorado River water.
- The indica-macrantha hybrid, Houri, has single, large wavy-edged flowers of light rose-lilac. It blooms profusely and blossoms all summer. It is evergreen.
Ideal Varieties For Pacific Northwest
The Kurume hybrids, which are evergreen, have an excellent floral display for the Pacific Northwest.
They are the following:
- Snow is a semi-double, hose-in-hose type, although sometimes it has large wavy-edged single flowers. The plants are compact and may lose a few leaves during hard winters.
- The Kurume hybrid, Hexe, is a semi-double, hose-in-hose type. It has bright crimson flowers and forms a dwarf, compact bush with dark foliage. It makes a good pot plant and throws an autumn bloom in the fog area. It is popular because of its hardiness and beauty.
- Twenty Grand is a deep-flowered plant and a persistent bloomer. In the fog areas, it may throw an autumn bloom.
For the Indicas, try the following:
- Paul Schame has flowers that are double coral-salmon flecked crimson. It blooms early and lasts through the summer. In milder coastal regions of the Northwest, it is popular as a background plant for blue primroses. It is evergreen.
- A deciduous azalea, Azalea occidentalis, has single flowers of white with a yellow blotch. Sometimes it is pink. It is the most fragrant of all azaleas, with erect, loosely-branched growth to 10’ feet tall. The foliage turns red and crimson in fall. It needs moisture and will grow in the sun or partial shade. It blooms from May to July.