SHRUBS > RHODODENDRON
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RHODODENDRON templet
Azalea vs RhododendronFeedingLeaves Wilting & Drooping
Rhododendrons can add up in many shapes and sizes and can be beneficial choices for gardeners with acidic grunge .
While some rhododendrons are invasive and not the well pick for eco - favorable spaces , many can be proficient pick for UK gardens where the required growing conditions are pronto available .
R. luteum
We ’ve join forces with Katrina Clow , Hon . Secretary of The Scottish Rhododendron Society , to help advise our rhododendron grow tips .
“ There are so many and in such variety , ” says Katrina , when asked why she is so passionate about growing rhododendrons .
“ They have stunning foliage and the flush make out in every color you could imagine . ”
R. luteum
Rhododendron is a large genus with over 1,200 natural specie – and many more cultivar besides.1About Rhododendrons . ( n.d.-b ) . Rhododendron Species Botanical Garden . retrieve March 23 , 2023 , fromhttps://rhodygarden.org/our-plants/rhododendrons/about-rhododendrons/
It is in the Ericaceae ( heather ) plant family.2Rhododendron . ( n.d . ) . University of Bergen . Retrieved March 23 , 2023 , fromhttps://www.uib.no/en/universitygardens/135136/rhododendron
Overview
PreferredPart Shade
ExposureSheltered
HeightVaries
R. barbatum
SpreadVaries
Bloom TimeSpring / Summer
PreferredClay , loam or sand
R.arborescens
MoistureMoist but well - drain
pHAcidic
Rhododendrons are often evergreen , but can also be deciduous .
The core of diversity are in Asia , though rhododendrons are also native to parts of North America and Europe.3Rhododendron . ( n.d.-b ) . Global Conservation Consortia . Retrieved March 23 , 2023 , fromhttps://www.globalconservationconsortia.org/gcc/rhododendron/
“ rhododendron are mostly native to the Himalayas and were premise to Britain in the eighteenth century , cross since then , ” say Katrina .
rhododendron are normally shrubs , though they can also be tree diagram , and alter considerably in size of it from less than 1 m in pinnacle and scatter , to up to ( more rarely ) 30 m tall .
Most of the rhododendron ordinarily grow in UK gardens are intermediate - sized to large shrubs , but there are also smaller options that are democratic choice for container growing .
“ They love the west seacoast of Scotland as we get high rainfall and humidity , ” excuse Katrina .
Common Varieties
We asked Katrina about her pet rhododendron varieties to grow .
“ This is a very difficult question , as there are so many , ” she allege .
“ When first grow rhododendron , you are probably attracted to the most brightly emblazon hybrid , but , gradually , the appealingness and beauty of metal money rhododendrons pass the glamour of hybrid .
“ They do take longer to flower but deserving the delay .
“ Evergreen azalea , yakushimanum hybrid , compact hybrids and tender fragrant rhododendrons are my favorite choices . ”
“ A particularly striking rhododendron for me isR. luteumwith intense yellow blossom , often borne before the leaves imprint . It is one I connect more with sunnier positions too , ” says Horticulturist Peter Lickorish .
“ However , this and some of the other metal money , includingR. ponticum , are class as non - aboriginal trespassing species and must be negociate cautiously to verify they do not diffuse beyond gardens .
“ In some forest , rhododendron is so tight - growing that it give up light reaching Sir Herbert Beerbohm Tree seedling and lower woodland plants . ”
Rhododendrons are often separate into spring unfolding option , which flower up to the end of April , and later flower varieties .
Some rough-cut other flowering rhododendron are :
Some vernacular late - flowering rhododendrons are :
These really are only a diminished fraction of the many choice that you could study .
“ Species rhododendrons may take several year to bloom but they are definitely worth look for , ” say Katrina .
“ Hybrids , in general , are problematical and will flower rather . ”
How To Grow Rhododendron
Rhododendrons should unremarkably be planted in either October or March to April .
Most rhododendrons are a salutary pick for a partially shaded smudge , either below trees(though not in deep shade ) or along a border in your garden .
Larger options work well in a forest garden .
However , most species and cultivar will be able to cope with a brighter and sunnier positioning as long as they are shelter from any air current that are inhuman and dry .
midget alpine species of rhododendron can usually tolerate full sun and will work well in a rock garden as long as the soil rest moist , whilst compact hybrids can be grow in container .
It is good to head off planting rhododendrons in frost pockets or anywhere where they are exposed to the sun in the early morning .
“ They can be grow in woodland gardens but they do require an acidulent growing medium , so gardens with chalk or very free - run out condition will not favour them , ” shares Katrina .
As Katrina explicate , most rhododendrons involve an acidulent grime or grow medium , with a pH of between 5 - 6 .
The soil should be dampish yet free - draining and rich in organic matter .
Rhododendron Care
Before planting a rhododendron , it is a good melodic theme to spreada thick layer of acidulous constitutional matterover the grime .
You should also mix organic cloth into the planting yap that you have make , blending it well with the excavated territory , before firming it back in around the bush .
Soil that is not acidic will have to be meliorate if you want to originate rhododendron .
However , it is generally best to plant for your soil type and to grow window pane - loving plants in containers if you do wish to get them , as Garden Designer Kate Gould explains :
“ The peachy thing about growing in pots is that you may command your soil .
“ Say you were gardening on chicken feed and you want to grow a rhododendron , you could do so in a pot because you could fill it with acidic dirt . ”
If you are turn rhododendron in container , check that that you use an ericaceous , peat - spare potting mix to occupy your pots .
Peat - destitute mixes can lick well for rhododendrons , but to quash compaction offspring , it is best to repot every other year into a fresh potting mix .
Rhododendrons have fairly mellow pee needs and will tend to grow good where there is high rude rain and will uprise less successfully in more desiccated areas .
check that that you irrigate regularly during teetotal periods , especially when growing in containers .
“ Flower bud lead off developing in late summer , so moisture is particularly significant – and sometimes in unretentive supply – at this prison term , ” tell Peter Lickorish .
“ Keep plants moist , but not waterlogged , ” Katrina only state .
attempt to use rain rather than solicit weewee to water your rhododendrons whenever possible .
In hard water district , rap water can be too alkaline and can slim down the sourness of the soil .
Renew the acidic mulch around your rhododendron each give , name certain that the filth or sensitive below is dampish before doing so .
It can also be beneficial to exchange the top 5 curium of the growing metier when growing your plants in container each winter and to feed the rhododendron over the summertime months with an organic liquidity feed .
“ Often if the stain is not acidulous enough for their recess preference , leafage will turn sensationalistic between the vein as they lack iron , ” adds Peter Lickorish .
“ liquidity feeds with an branding iron content can slim down this hurt . ”
Propagating rhododendrons is not an easy caper for novice gardener .
However , it is sure as shooting potential to obtain new plants from those you already produce .
The most important matter to sympathize before you begin is that only some specie of rhododendron will come true when grown from seed .
Named cultivars have to be propagated by means of semi - good cuttings or through more complex method like graft or layering .
Taking rhododendron cuttings is typically the easiest generation method acting .
Cuttings are taken from the current twelvemonth ’s stems , in late summertime or autumn , once the bud has developed fully .
The clipping should be direct with a dog and the radical should be wounded more or less to encourage it to take theme .
Cuttings of evergreen rhododendrons can also be taken in July or August .
Deciduous rhododendrons are more hard to diffuse from clipping , which is why this is normally only done in a commercial setting .
For specie rhododendron which will amount true from seed , seeds should be sow in January indoors , with the seeds left unveil on the surface of the growing medium .
These wad should be place inside a het up propagator .
Pruning is not usually required for rhododendrons .
You may just rationalise these bush to remove numb , damaged or pathological cloth and can deadhead drop flowers to improve the bush ’s appearance if you want to .
“ Deadhead to get good heyday the following year if you want to improve your rhododendron shrubs , ” partake in Katrina .
you could also prune back many rhododendron to restrict their size after flowering .
roughly - barked rhododendrons will run to respond better to severely pruning than smooth - bark type .
“ Pruning too late , such as in the autumn , is potential to significantly reduce flowering the following year , ” according to Peter Lickorish .
“ Often it is preferable to rationalize in other summer , as long as flowering has finished , and reduce a third of the longer stems each yr to restore an overgrown plant life back to [ a ] manageable sizing .
“ calculate to prune to a bud if possible . If you do prune back hard , be sure to mulch and water system well afterwards to ensure strong new increase . ”
Many problems you may experience with a rhododendron shrub are potential to be due to environmental or aid issue rather than pests or diseases .
For example , non - flowering bush may not produce blooms because of under - watering or improper pruning .
folio drop cloth may also be due to a lack of water , waterlogging , extreme photograph to cold or another environmental proceeds .
alimentary want can have issues like the yellowing of foliage .
However , common cuss and diseases can also strike rhododendron .
Common pest includevine weevils(especially when the shrubs are container - grown ) , leaf - hoppers and scale insect .
Some rhododendron diseases include azalea crust , bud blast andhoney fungus .
“ Anything you like that looks comfortable and revel the same conditions as your rhododendrons can be planted with them , ” say Katrina , when discussing what to grow with rhododendron .
Some of her favourite works to grow alongside them include :
“ Shrubs that like ericaceous weather , such as enkianthus or kalmia , and trees which create light shade , like magnolia , will add social structure to your planting , ” Katrina sum up .
“ There are many beautiful Rowan cultivar with different dark berries and fall leaf colour which can also wreak marvelously .
“ I also like to add hydrangea for late flower . ”
