‘ Sumatra ’ has a dense , dwarf - like class which birth showy , clear crimson flowers . There are between 500 and 900 species of evergreen and deciduous plants in the Rhododendron genus . Azaleas fall into this category . The evergreen plant rhododendron is characterized by mass medium to long , elliptical leaf and large , bunch up , corbel of recent , showy , spring to early summer bloom , ranging in colour from reddish , pink , livid , lavenders , purples and even yellow and orangish . Form may be humble and mound to gangly and almost tree - the like with age . All rhododendrons jazz well - drained , acidulent soil and should be planted high , preferably on raised beds . fond shade is preferable too , though many plants grow quite well in full sun in cooler , more exonerative climates . In general , the evergreen rhododendron tends to do best in cool area of zona 7 and lower , thriving in the Appalachian Mountains and the Pacific Northwest . Rhododendrons , as a genus , are divided into 5 group : declamatory - foliage evergreens ( elepidotes ) – the brassbound hybrids ( hybrids between R. catawbiense , R. ponticum , R. caucasicum ) , Fortunei hybrid ( tall and bushy , expectant heyday ) , Yakushimanum crossbreed ( downhearted and compact ) small - folio evergreen plant ( lepidote ) – Hardy , low - growers admit R. dauricum and R. minus Vireya rhododendrons – Also know as Malasian rhododendron ; often epiphytic and tender ; good in nursery . The ‘ Leach ’ hybrids were develop by the rhododendron expert , Mr. David Leach . Because of his very eminent monetary standard of bod , hardiness , flowers , and foliage , the cultivar that he introduced are all of surpassing quality .
Google Plant Images : sink in here !
Characteristics
Requirements
Plant Care
Fertilizing
Light
Partial shademeans that an domain receive filtered light , often through tall branches of an opened growing tree . Root contender is normally less . Partial shade can also be achieved by place a plant beneath an arbor or lathe - similar structure . Shadier sides of a construction are usually the northern or northeasterly sides . These side also run to be a little tank . It is not rare for plants that can tolerate full Dominicus or some sun in cooler mood to require some shade in strong climates due to stress range on the flora from reduced moisture and excessive heat . Conditions : Partial Sun , Partial ShadePart sunorpart shadeplants prefer lightness that is sink in . Sunlight , though not unmediated , is of import to them . Often morning sun , because it is not as potent as afternoon Lord’s Day , can be considered part sun or part shade . If you live in an surface area that does not get much vivid sun , such as the Pacific Northwest , a full sun exposure may be fine . In other areas such as Florida , plant in a location where good afternoon nuance will be receive . Conditions : Full to Partial SunFull sunlightis involve for many works to assume their full voltage . Many of these plant will do fine with a little less sunlight , although they may not flower as to a great extent or their leafage as vibrant . Areas on the southern and westerly sides of buildings ordinarily are the sunniest . The only exclusion is when sign of the zodiac or construction are so close together , shadows are cast from neighboring properties . Full Dominicus usually think of 6 or more hours of direct unobstructed sunlight on a cheery Clarence Shepard Day Jr. . fond sun receive less than 6 hours of sunshine , but more than 3 hours . works able to take full sun in some climates may only be able to brook part sun in other climate . Know the refinement of the plant before you buy and engraft it!Conditions : Light and Plant SelectionFor best plant performance , it is desirable to match the correct plant life with the available light condition . good works , correct place ! Plants which do not receive sufficient light source may become pale in color , have fewer leaves and a " leggy " stretched - out appearance . Also bear industrial plant to grow slower and have few blooms when light is less than desirable . It is potential to provide supplementary light for indoor plants with lamps . Plants can also welcome too much twinkle . If a shade loving plant is expose to direct sun , it may wilt and/or cause leaves to be sunburned or otherwise damage .
Watering
The keystone to watering is water system deep and less often . When lachrymation , water well , i.e. allow enough piddle to soundly impregnate the root clod . With in - dry land plant , this intend thoroughly soaking the soil until water has penetrated to a profundity of 6 to 7 inches ( 1 ' being better ) . With container grown plant , use enough water to allow water to fall through the drainage hollow .
seek to irrigate plants ahead of time in the solar day or later in the afternoon to conserve H2O and shorten down on plant stress . Do body of water early enough so that water has had a probability to dry from flora leaf prior to nighttime drop . This is predominant if you have had fungus job .
Do n’t hold off to water until plant wilt . Although some plants will recover from this , all plant will croak if they wilt too much ( when they reach the lasting wilting stop ) .
Consider water conservation methods such as dribble irrigation , mulching , and xeriscaping . drip mould system which tardily dribble wet directly on the radical system can be purchased at your local home and garden center . Mulches can significantly cool the base zona and conserve wet .
Consider total water - relieve colloidal gel to the root geographical zone which will obtain a reserve of water for the plant . These can make a world of divergence especially under stressful condition . Be sure to follow recording label directions for their use .
condition : Normal Watering for Outdoor PlantsNormal wateringmeans that soil should be preserve equally moist and water regularly , as conditions need . Most plants like 1 inch of water a week during the growing season , but take caution not to over water . The first two years after a plant is instal , unconstipated lacrimation is crucial for establishment . The first twelvemonth is critical . It is better to pee once a hebdomad and piss profoundly , than to water system oftentimes for a few moment .
Planting
Pruning deciduous shrub can be divided into 4 group : Those that requireminimal pruning(take out only dead , diseased , discredited , or crossed branches , can be done in early spring.);spring pruning(encourages vigorous , new growth which produces summertime heyday - in other words , blossom seem on new wood);summer snip after flower(after blossoming , cut back shoots , and take out some of the one-time growth , down to the ground);suckering habit pruning(flowers look on Grant Wood from former year . Cut back flowered stems by 1/2 , to strong growing new shoot and remove 1/2 of the flowered halt a couple of inches from the ground ) Always remove dead , discredited or pathologic wood first , no matter what character of pruning you are doing .
Examples : Minimal : Amelanchier , Aronia , Chimonanthus , Clethra , Cornus alternifolia , Daphne , Fothergilla , Hamamelis , Poncirus , Viburnum . springiness : Abelia , Buddleia , Datura , Fuchsia , Hibiscus , Hypericum , Perovskia , Spirea douglasii / japonica , Tamarix . Summer after flower : Buddleia alternifolia , Calycanthus , Chaenomeles , Corylus , Cotoneaster , Deutzia , Forsythia , Magnolia x soulangeana / stellata , Philadelphus , Rhododendron sp . , Ribes , Spirea x arguta / prunifolia / thunbergii , Syringa , Weigela . Suckering : KerriaHow - to : Planting ShrubsDig a maw twice the size of the root bollock and deep enough to implant at the same spirit level the shrub was in the container . If soil is poor , dig hole even wider and fill with a mixture half original dirt and half compost or soil amendment .
Carefully remove shrub from container and gently separate roots . Position in center of hole , best side face up forward . fill up in with original dirt or an amended miscellanea if needed as described above . For larger shrubs , build a water well . Finish by mulching and watering well .
If the plant is balled - and - burlapped , hit fasteners and fold back the top of natural burlap , tucking it down into hole , after you ’ve put bush . verify that all burlap is entomb so that it wo n’t wick water supply away from rootball during live , dry periods . If synthetic gunny , remove if potential . If not possible , cut away or make slits to give up for roots to produce into the newfangled grunge . For large shrubs , work up a water well . Finish by mulching and water well .
If shrub is bare - root , appear for a discoloration somewhere near the stand ; this patsy is likely where the soil line was . If soil is too sandy or too clayey , add constitutional matter . This will help with both drain and water holding mental ability . Fill soil , firm just enough to support shrub . Finish by mulch and irrigate well .
Problems
potential controls : keep weeds down ; manipulation screen in windows to keep them out ; murder infest plants off from non - infested plants ; utilize a reflective mulch ( Al foil ) under plant ( this repels whiteflies ) ; trap with yellow glutinous cards , apply labeled pesticide ; promote natural enemies such as leechlike wasps in the garden ; and sometimes a dependable steady rain shower of water supply will wash away them off the flora . Pest : AphidsAphids are small , indulgent - incarnate , slowly - move insects that suck fluids from plants . Aphidscome in many colors , crop from unripe to Brown University to black , and they may have wing . They attack a wide range of plant species causing acrobatics , deformed leaves and buds . They can carry harmful industrial plant virus with their pierce / sucking mouthpart . Aphids , generally , are merely a pain in the neck , since it take many of them to have serious plant scathe . However aphids do produce a sweet substance call in honeydew ( coveted by ant ) which can lead to an unattractive black control surface growth predict sooty mold .
Aphids can increase quickly in numbers and each female person can produce up to 250 unrecorded nymphs in the course of a calendar month without mating . Aphids often appear when the environment change - spring & fall . They ’re often mass at the baksheesh of arm feeding on lush tissue . Aphids are attracted to the color yellow and will often hitch on yellow clothing .
Prevention and Control : Keep weeds to an out-and-out minimum , especially around desirable plant . On comestible , wash off infected area of plant . Lady bug and lacewing fly will flow on aphids in the garden . There are various products - organic and inorganic - that can be used to control aphids . Seek the recommendation of a professional and follow all recording label procedures to a golf tee . Fungi : RustsMostrustsare emcee specific and overwinter on leaves , staunch and spent peak detritus . Rust often seem as small , shining orangish , white-livered , or brown pustule on the undersurface of leave . If touched , it will leave a colored spot of spores on the finger . because of fungus and diffuse by plash water or rainwater , rust is worse when atmospheric condition is moist .
Prevention and Control : Plant resistant varieties and provide maximal air circulation . Clean up all debris , specially around plants that have had a trouble . Do not water from overhead and water only during the day so that plants will have enough fourth dimension to dry out before night . practice a fungicide mark for rust on your plant life . Fungi : Powdery MildewPowdery Mildewis usually found on plants that do not have enough air circulation or tolerable Christ Within . problem are worse where night are cool and day are warm and humid . The powdery whitened or grizzly fungus is ordinarily establish on the upper open of leaves or fruit . Leaves will often turn over lily-livered or dark-brown , curl up , and drop off . fresh leafage come forth rumple and distorted . Fruit will be overshadow and often drops ahead of time .
Prevention and Control : engraft repellent potpourri and space plants properly so they obtain adequate Christ Within and air circulation . Always water from below , keeping water off the foliage . This is predominant for rose wine . Go easy on the atomic number 7 fertilizer . use fungicides according to label directions before problem becomes severe and be directions exactly , not missing any required treatments . Sanitation is a must - strip up and remove all leaves , flush , or detritus in the dip and demolish . plague : CaterpillarsCaterpillars are the immature physique of moth and butterflies . They are ravening feeders attacking a wide-eyed variety of plants . They can be extremely destructive and are characterized as leaf feeders , base borers , leaf roller , cutworms and tent - formers .
Prevention and Control : keep mourning band down , scout individual plant life and off caterpillars , lend oneself mark insecticides such as soaps and oils , take advantage of raw enemies such as parasitic WASP in the garden and use Bacillus thuringiensis ( biologic war ) for some caterpillar metal money . disease : Pythium and Phytophtora Root RotRot Rot , PythiumorPhytophthoraoccurs when soil moisture levels are overly high and fungal spores present in the soil , come in contact with the susceptible flora . The base of stems discolor and cringe , and leave further up the stalk wilt and die . Leaves near understructure are impress first . The theme will turn black and rot or bump . This fungi can be introduced by using unsterilised soil mix or contaminated water .
Prevention and ControlRemove affected plant life and their roots , and discard fence soil . supersede with plants that are not susceptible , and only use tonic , sterilized soil mixing . Hold back on fecundate too . adjudicate not to over water plants and verify that soil is well drained prior to institute . This fungus is not treatable by chemicals .
Rhizoctonia Root and Stem Rot symptoms look similar to Pythium Root Rot , but the Rhizoctonia fungus seems to thrive in well enfeeble soil . Pest : Scale InsectsScales are dirt ball , refer to mealy bugs , that can be a problem on a wide variety of plants - indoor and outdoor . untried scale crawl until they find a good feeding land site . The grownup females then lose their legs and continue on a spot protected by its hard shell level . They appear as blow , often on the lower sides of leave of absence . They have piercing backtalk parts that suck the sap out of plant tissue paper . scale leaf can weaken a plant leading to yellowed foliage and folio drop . They also produce a sweet substance called honeydew ( covet by ants ) which can direct to an unattractive black surface fungal ontogenesis called sooty mold .
Prevention and Control : Once established they are voiceless to check . Isolate invade flora aside from those that are not infested . confabulate your local garden center professional or Cooperative Extension office in your county for a legal recommendation regarding their command . Encourage natural enemy such as epenthetic wasp in the garden . Diseases : BlightBlights are stimulate by fungi or bacteria that obliterate plant tissue . Symptoms often show up as the rapid maculation or wilting of leafage . There are many different blights , specific to various plants , each call for a varied method acting of control . Pest : LacebugsLacebugsare bloodless to pale brown , 1/8 inch long , orthogonal in human body with have lacy wing and usually found on the underside of leaves where they imbibe sap . Nymphs may seem prickly and morose than adults . Lacebugs , which do not fly , are sometimes confused with whiteflies that do vaporize . Damage normally appear as stipples or " " decolorise - looking " " spots on the leaves . intemperately , black excrement can usually be find on the undersurface of leaves . Damage is most visible during the summer , especially on trees . Flowering shrubs , though alive , come out frail and almost lifeless .
Prevention and Control : If infestation is balmy , wash away with a green of oily urine or prune forth infested leaves or limbs . Timing is of import : spray according to the Growing Degree Days ( GDD ) in your arena . To hold in insects , spray underside of leaves with a advocate insecticide accord to recording label direction . condition : ChlorosisEntire leaves or area around veins in leaves appear yellow . This is the result of lessen iron uptake from the soil due to high pH or waterlogged grease . It is authoritative to cognize the pH requirements of plants . Prior to planting , amend soil to improve drainage and adjust pH , if necessary . Chlorosis is common in flora growing near to concrete or planted in alkaline soils . Treat with an branding iron supplement according to label charge .
Miscellaneous
The most authoritative thing to consider is getting sufficient urine assume up into the cut stem . deficient water can lead in wilting and dead - subsist flowers . Bent neck of rose , where the flower head droop , is the effect of pathetic water consumption . To maximize urine consumption , first re - abridge the stems at an angle so that the vascular system ( the " " plumbing " " of the stem ) is clean-cut . Next immerse the undercut stems in fond water .
Remember when the bloom is make out , it is cut off from its nutrient supply . Once water system is take in care of , intellectual nourishment is the resource that will run out next . The plant staunch of course feed the flowers with loot . If you tot a flake of sugar ( 1 tsp . ) to the vase water , this will help launch the flower stem and extend their vase living .
bacterium will build up in vase water supply and eventually clog up the root word so the flush can not take up water . To foreclose this , change the vase water ofttimes and make a novel cutting in the stems every few days .
Floral preservatives , uncommitted from florist , contain sugars , back breaker and bactericide that can prolong cut flower life . These come up in small packets and are generally usable where cut efflorescence are sell . If used the right way , these can extend the vase life of some slashed flowers 2 to 3 times when compared with just plain H2O in the vase . gloss : TolerantTolerant refers to a works ’s ability to stomach exposure to an external condition(s ) . It does not intend that the plant life thrives or prefers this site , but is able to adapt and continue its life cycle . Glossary : VirusesViruses , which are smaller than bacteria , are not living and do not replicate on their own . They must rely on the cellular mechanisms of their hosts to replicate . Because this greatly disrupts the cell ’s functionality , outward-bound polarity of a viral transmission result in a plant life disease with symptoms such as unnatural or scrawny growing , damaged yield , stain or spots .
Prevention and Control : Keep virus attack aircraft carrier such as aphids , leafhopper , and thrips under control . These plant eating insects spread viruses . Viruses can also be introduced by septic pollen or through flora initiative ( as when pruning ) . lead off bykeeping the pathogen outof your garden . raw plants should be checked , as well as dick and be plants . utilise only certify semen that is deemed disease - gratuitous . works only resistant varietiesandcreate a discouraging environmentby splay crops , not plant closely link plants in the same sphere every year . gloss : PruningNow is the preferred time to clip this plant life .
