Azaleas are deciduous or evergreen shrubs admired for their fertile showing of flowers and their plant figure . Although many innovative azaleas are the result of complex hybridization , they stay well suitable to temperate climate regions where there is a cool to cold-blooded wintertime sleeping and lovesome to hot summertime . They also are sold as seasonal houseplant where non - freezing but cool temperature sustain the retentiveness of bloom .

Classification

All azaleas botanically are rhododendrons ( Rhododendron spp . ) , but are further grouped into subgenus Pentanthera and Tsutsusi establish on floral and foliage characteristics , among others . The unwashed name azalea is broadly yield to small - leaved bush that are either deciduous , lose their leaf in winter , or evergreen plant . Many intercrossed azalea have been developed over decades , and thus many subgroupings of azaleas exist , including deciduous types like Ghent , Mollis , and Knap Hill - Exbury hybrids as well as evergreen type like Indica , Kuruma , Satsuki or Robin Hill cross .

It is of import to understand the temperature needs and limitations for the hybrid azalea subgrouping . Often a industrial plant tag will heel the specific cultivar name of the azalea as well as the subgrouping type . For example , cultivar Gibraltar is a Knap Hill - Exbury azalea , and should be given maintenance and conditions appropriate for that deciduous azalea subgroup .

Uses

Azaleas serve both an outdoor landscape and an indoor forced - blossom houseplant intention . Outdoors the azalea shrub brings greenery and form to timberland garden , motley shrub borders or foundation planting . sure miscellanea of azalea , found on their uprise characteristic , have been employ in the florist industry as small potted talent plant that can be force into rosiness at different times of year . Temperature during the growing season and during the necessary quiescence are important for the health of the azalea plants as well as ripe efflorescence .

Cold Hardiness

With a wonderful number of azalea loanblend and varieties , pinpointing an precise terminal point on wintertime cold hardiness is hard . However , in the main speak , deciduous azalea tolerate lower wintertime temperatures much well than their evergreen plant counterparts . Northern Lights azalea have been developed to survive in wintertime climates where temperatures often reach -15 to -25 degrees F. Most types , however , may only withstand winter cold to -5 to 10 degrees F , and other factors such as continuance of the cold or soil wet can contribute to the individual azalea ’s power to tolerate winter frigidity .

Without an annual period of growth followed by a dormancy with cool to cold temperatures , the azalea will not copiously produce flowers , if at all . There are exceptions to this because of all the genetical variety in the hybrid today , but these shrubs are not continually flowering . Excessive common cold or an unseasonably late spring frost or freeze can destroy emerging leaves and bloom buds , too .

Heat Hardiness

Conversely , azalea are not tolerant of elongated high temperatures outdoors of the summer . Some evergreen plant group , like the Indica hybrids , are well adapt to region with long , hot summers , but prolonged photograph to heat , that above 90 degrees atomic number 9 , can degrade plant . Even in the warm climate area along the American Gulf Coast , significantly cooler decline , winter and spring temperatures prevail for coherent florescence .

Azaleas are not adapted for sustained outgrowth in tropical or subtropical climates , except where mountain elevations help make a climate that is more like that of the temperate clime zona .

Seasonal Considerations

Whether grown outside in the garden or enjoy in a flower pot on the kitchen table , azalea plants must be exposed to temperatures within the range of approximately 0 to 90 point F. When actively growing or in peak , the temperature kitchen stove certainly must be above 32 degrees F. The tank the temperature , the slower the growth rate . Thus , if a flower presentation in spring is exposed to cool temperatures , such as 40 to 50 degrees F , the blooming will last longer on the plant , extending the display . If temperatures are mellow , 70 to 80 degrees F , flower will open and fleet at a fast rate .

Indoor houseplant azaleas should be placed out of cooking stove of heating and breeze - conditioning registers so that their drying spicy or moth-eaten breezes do not affect the plants . To prolong the flowering indoors , temperatures below 65 degrees F would be ideal , and keep plant out of direct sunshine can cut watering needs and heating plant of leaf and bloom .

References

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