Black tips on Satsuki Azalea Kobai leaves…

[Tumpet2000]

Hello all,

As shown in the attached pictures, the tips of my Satsuki Azalea Kobai leaves are turning a black/brown colour?

Should I worry? Or is this ordinary?

Thanks.

 

[Leo in N E Illinois]

You will have to decide which of these possible causes is relevant.

Just a bit too dry between watering. In which case if watering frequency has improved, the problem won't continue.

Just a bit too wet, though here the new growth would show more damage too.

Too much fertilizer.

Heat stress - you did not fill out location in your profile, so have no clue if this is a possible problem. Azalea should be moved to shade when temperatures are over 95 F (35 C), azalea also like to cool off at night. Heat stress can show up is night temperatures do not drop below 80 F (27 C) at night. Sun on the pots can heat the roots up. The trick is to keep pots somewhat shaded while getting sun to the leaves. Some use cardboard or aluminum foil to keep the roots in shade while leaves get sun. The right amount of sun is about a half day to three quarter day of sun.

 

[sorce]

Oops.

Welcome to Crazy!

Sorce

 

[Deep Sea Diver]

You will have to decide which of these possible causes is relevant.

Just a bit too dry between watering. In which case if watering frequency has improved, the problem won't continue.

Just a bit too wet, though here the new growth would show more damage too.

Too much fertilizer.

Heat stress - you did not fill out location in your profile, so have no clue if this is a possible problem. Azalea should be moved to shade when temperatures are over 95 F (35 C), azalea also like to cool off at night. Heat stress can show up is night temperatures do not drop below 80 F (27 C) at night. Sun on the pots can heat the roots up. The trick is to keep pots somewhat shaded while getting sun to the leaves. Some use cardboard or aluminum foil to keep the roots in shade while leaves get sun. The right amount of sun is about a half day to three quarter day of sun.

Excellent synopsis @Leo in N E Illinois !

I would be nice to know @Tumpet2000 what media mix you are using. If the Kobai is still in nursery mix, my first bet would be fertilizer, closely followed by overwatering or both. It would be pretty obvious if you’d underwatered in that case as you’d probably have to submerge the pot to rehydrate the media.

If the tree is in a bonsai mix, it would be a crapshoot which issue you caused this.…. except if you are in kanuma, then I’d bet overfertilization followed by underwatering.… you really can’t overwater a satsuki in kanuma…. well… you’d really have to work hard at it!

If you think you might be overwatering, then you could back off a bit and mist inbetween watering. Remember watering is dependent on the soil moisture level. Azaleas like moist soil, but not wet.

Regarding high temperatures, it’s likely more like 90 degrees F for plant shutdown for azaleas. 95F would be absolute though. Narrow leafed cultivars shutdown first. Kobai is rounded, so it can take more heat.

I forgot about Ye Olde aluminum foil trick! Thanks for the reminder .

Tumpet - to add your location and USDA Zone so we can tailor advice please double click you icon on top and enter your approximate location.

cheers
DSD sends