These beautiful blooming shrubs have many varieties and can grow outdoors in most locations. This guide is about growing azaleas.
Spring and fall are the best times to purchase and plant azalea and rhododendron clumps.
|Life Cycle:||perennial landscaping shrub|
|Planting Time:||spring or fall|
|Height:||1' to 12' or more|
|Soil:||rich, moist, well-drained soil with an acidic pH|
|Hardiness:||zones 5 to 8|
|Bloom Time:||early spring to summer depending on zone|
|Flower:||white, pink, lavender, violet-blue, yellow, orange and red|
|Suggested Use:||landscaping shrubs|
|Growing Hints:||Spring and fall are the best times to purchase and plant azalea and rhododendron clumps. If you buy whole balled or burlap wrapped plants, late summer is the best time for planting. You can grow both of these plants from 4 " cuttings taken in late spring and early summer. Dip cuttings in a rooting hormone, insert them into a moist propagating mix and cover them with plastic, making a mini greenhouse supported with bent wire. Keep cuttings moist and out of direct sun until they root (weeks or months). Remove plastic, harden them off and transplant them. The best sites for azaleas and rhododendrons are sites with loose, hummus-rich soil that is evenly moist and has a pH of 4.5 to 6.5. Pruning should be done immediately after flowering. Do not plant near walnut trees.|
|Interesting Facts:||Rhododendrons have 10 or more stamens, bell-shaped flowers, and leaves that are usually evergreen, while azaleas have 5 stamens, funnel-shaped flowers, and deciduous leaves. Gardeners see these as two different plants, but botanists lump them into one genus (group).|
Azaleas are beautiful and versatile in the landscape. They come in a variety of shapes, colors and sizes, and have a wide enough hardiness range that even gardeners in the coldest of zones can enjoy growing them. These ornamental shrubs are very particular about the conditions they grow in-especially the soil. They are not necessarily more difficult to grow than other landscape shrubs, as long as you give them what they need.
Soil preparation: Start with a soil test. Azaleas prefer acidic soil with a pH range of somewhere between 4.5 to 6.0. They will suffer and fail to thrive in alkaline soil. The results of your soil test will tell you what you need to add (e.g. sulfur) to adjust the pH. Once amended, you can keep the soil acidic by adding a cup of sulfur to the soil around each plant in the early spring.
Moisture: Adequate moisture is critical for azaleas, especially while becoming established. Although they prefer moist soil, they also need adequate drainage to prevent soggy roots. If you have clay soil, you'll need to amend it with equal parts of coarse sand and organic matter or consider growing these shrubs in raised beds to improve drainage. Gardeners with sandy soils should double up on the organic matter (hummus) to help the soil retain moisture long enough to be taken up by the roots.
Mulching: Azaleas have shallow root systems, so be very careful when working around the base of them. They will benefit greatly from a few inches of acidic mulch (pine bark, pine needles, or oak leaves) applied around the base, which will protect their roots and help conserve moisture.
Fertilizer: As with exposure to light, pruning, and other aspects of cultivation, azaleas prefer being fed in moderation. Both dry and water-soluble organic fertilizers specially formulated for azaleas are readily available at most garden centers. Once the plants establish their roots, most recommend scattering a handful of slow release organic fertilizer near each plant once in the early spring and again in the fall (dry), or dissolving a small amount in water (wet) and feeding plants every three weeks. Always read and follow directions on the label carefully.
As for the practice of putting fertilizer directly in the bottom of the hole when planting-don't do it! Their roots are shallow and easily burned and the results can often be fatal.
My azalea is in full bloom now, thought I would share the gorgeous color with everyone. Hope you vote thumbs up if you like them.
By Linn from Canada
My azalea bushes are 20 years old. Several years ago, I pruned them back severely, because they were getting very leggy and sparse. This spring they did not bloom for the first time in years. I found that they enjoyed an acid soil. Instead of mixing up pickling vinegar (which is the best), I use the juice from a pickle jar any other jars that have vinegar in them. After I have eaten all of the pickles, instead of pouring the juice down the drain when the jar is empty. I pour it over my Azalea plants. They do seem to love it and are thriving.
By xintexas from San Antonio, TX
Hardiness Zone: 5b
MinDee from Missouri
I wouldn't worry about cleaning them up unless you have had problems in the past with insects or fungal diseases. If this is the case, the fallen leaves will make a nice place for insects and disease spores to spend the winter so you're better off disposing of them (don't compost). If insects and disease are not a factor, I see no harm in leaving them. After all, the leaves can also make an attractive place for beneficial insects to overwinter. The way I look at it, when in doubt, always follow nature's example. Without human intervention, plants naturally rely on the insulating properties of their own leaves to protect them from the elements and provide nutrients again in the spring. Because most of the plants in our gardens are forced to adapt to "artificial" growing conditions, we've got to help them compensate. That said, you will probably want to add some mulch to the leaves anyway, unless you think you have enough leaves to provide adequate winter protection.
Azalea bushes love acidic soils--to add acidity, rake
away the leaves that have fallen around the azaleas, and mulch around them with some pine
needles. They will LOVE you for it!!!!
I received an azalea rhododendron hybrid plant for Mother's Day and don't know what to do with it. Is it an outdoor plant or indoor? I live in southern Ohio. I also need to know how large it will grow. Or is it considered a bush?
By Peggy C
Do you believe it ? The Ohio State University is providing you with a full page of information. Titled of the page is " Growing Rhododendrons and Azaleas in Ohio " and it is here : http://ohioline.osu.edu/hyg-fact/1000/1078.html
What more do you need ? Maybe just this about plants in full bloom sold for Mother's day or any other big date. To force full bloom at a given time plants are usually either "heated" or kept in darkness and suddenly exposed to full light 24 hours a day or overdosed with fertilisers. Your Azalea may also be potted with coconut fibers only. This type of soil can provide nutriments for the plants for a few weeks only. Once you have found its future place in your garden let the plant stay in water at room temperature until it is completely soaked take the plant out of the water, throw the water away and repeat the process. This way you will get rid of the extra fertilizer. Avoid fertilizing during the first year. If your Azalea is in a suited place in your garden with the proper soil and receives the right amount of water it will not need fertilizer.
Good luck !
When we moved into our house last fall, we had no idea that the huge overgrown bushes along the driveway, were this beautiful in the spring. I'm so glad we decided to wait to trim them, until we saw them for a full season.
By Patricia N.
It's summertime and hot here in Virginia. Why are my azaleas blooming in the summer?
By Barbara from Yorktown, VA
When is the best time to prune rhododendrons and azaleas?
By Jess from Hillsboro, OR
Right after the last bloom begins to look 'ugly'. Wait too long, and you take the risk of new bloom sets being pruned off. Next years blooms take shape soon after the last bloom of the current year fades, so pruning at the wrong time will cut off all those buds for next year and all you'll have is a green shrub in your garden.
When you do your pruning, make sure to disinfect your shears between plants to avoid transferring any fungi or pests from plant to plant (sometimes very hard to see until damage-infestation is killing your plant).
Also, open the interior of the bush a bit, and remove all crossed/rubbing branches/stems to keep fungi and aphids from finding an attractive home.
These plants are some of the most beautiful garden plantings, especially when planted in masses, but they do need to be pruned at the right time. :)