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Pink azalea

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Got gardening questions? Contact the Hortline at (515) 294-3108 (M-F; 10-12 & 1-4:30) or send an e-mail to hortline@iastate.edu. For more gardening information visit us at Yard and Garden Online (www.yardandgarden.extension.iastate.edu)




I recently received a flowering azalea as a gift. Can I plant it outside in the spring? 


Azaleas sold by florists are not winter hardy outdoors and are normally discarded after flowering. However, the azalea can be kept as a houseplant. After the plant has flowered, place the azalea in a sunny east or west window. Proper watering is extremely important. Check the potting soil frequently. Thoroughly water the plant when the soil surface becomes dry to the touch. Discard any excess water.  Wilting and leaf drop may occur if the potting soil is allowed to get too dry. Wet soils can lead to root rot problems. When the azalea begins to grow, fertilize monthly with an acid-type fertilizer. 


The azalea can be moved outdoors in late May. Select a site in partial sun. A site that receives morning sun and afternoon shade is generally a good site. Don’t remove the plant from the pot, simply dig a hole and set the pot in the ground up to its rim. Be sure to water the plant during dry weather. Fertilization should be discontinued in mid-summer.


While difficult, it is possible to get the azalea to bloom again. Flower initiation occurs in late summer/early fall in response to cool temperatures. Bring the plant indoors right before the first hard frost. Indoors, place the azalea in a well-lit, cool location. Keep the soil evenly moist. If the plant receives the proper care, the azalea should bloom sometime in winter. 


Is it possible to transplant an established grapevine? 


The roots of a grapevine often penetrate to a depth of 3 to 5 feet. As a result, transplanting an established grapevine is difficult if not impossible. The best way to save an old grapevine is by taking hardwood cuttings. 


Hardwood cuttings are taken from the dormant vines of the previous season’s growth. The best time to collect cutting material is late February or March. Cuttings should be approximately pencil-size in thickness and 12 inches long. The bottom cut should be just below the lowest bud, while the upper cut should be 1 to 2 inches above the top bud. 


If the ground is still frozen, loosely tie the cuttings in a bundle, place them in a plastic bag with some damp peat moss, then store them in a cool location, such as a refrigerator. 


As soon as the soil is workable in spring, remove the cuttings from storage and set them in the ground vertically with the top bud just above the soil surface. Water the cuttings during dry periods in spring and summer. Those cuttings that root and grow can be transplanted to their permanent location before growth begins the following spring. 


When should I start impatiens seeds indoors? 


Impatiens are relatively easy to grow from seeds. However, they are rather slow growing. Home gardeners should sow impatiens seeds indoors in late February or early March. Immediately after germination, place the seedlings under fluorescent lights. (Plants grown in sunny windows often get tall and spindly because of insufficient light.) Position the lights no more than 4 to 6 inches above the growing plants. Leave the lights on for 12 to 14 hours each day. Harden the plants outdoors for several days before planting them into the garden. 



Contacts :

Richard Jauron, Horticulture, (515) 294-1871, rjauron@iastate.edu

Jean McGuire, Continuing Education and Communication Services, (515) 294-7033, jmcguire@iastate.edu

Two photos are available for this week's column.

Purple Azalea   (LavenderAzalea1-25-06), 1.8 MB

Pink Azalea,   (CUPinkAzalea, 1-25-06), 1 MB