Buxus turning yellow after watering

A few days ago when we had that warm weather I decided to power wash my front path and water my adjacent buxus boxes with my hosepipe. Yesterday I noticed one of them was starting to turn yellow on top and along one of the sides and today it's gone much worse and it's also looking a bit black rather than the lush bright green colour that it uses to be. I'm worried that it's been affected by either the chemicals in the water or maybe there's been something on my path that's washed in to the soil.

A couple of months ago when we had all that snow I put rock salt down on the path and washing the paving slabs next to it may have washed some of the residue salt in to the soil. I'm clearly grasping at straws here and only guessing but I'm sure it's not any kind of blight or disease as it's been healthy for many years until the recent watering. I also gave it a trim to shape it up prior to watering so don't know if it's just scorched as the damage mainly seems to be on the top where I trimmed it but it's gone very dark and some of the leaves have turned black.

Not sure if I should give the plant a thorough soaking to wash away any potential chemicals or whether that will just make it worse.

This has happened to me before with exactly the same species when I washed my patio and the water ran off in to my borders. The box never recovered and I ended up having to rip it out after all the leaves turned white and dropped off. I don't want to have to go through that again as it's quite an established box which has taken me about 5 years to get to this size and shape.

Any ideas?

 

My guess is that it could be salt, did the water you used contain any cleaning chemicals?
On the other hand it looks very similar to a problem I have had with box in the past, it can scorch in the sun, and that usually happens after trimming.

Cant remember exactly but there is a time to trim box in order to stop scorch, I need to look it up

 

I’m with Pete. I think there may have been salt from before still around that part of your garden and the hose has transferred it to the plant. The salt and sun act very similar in their drying tendencies.

 

Salt would do that but so would applying water on a hot day. New "sensitive" growth would be vulnerable to watering on a hot day The Wizard. I would guess the watering rather than the salt. Nothing to do with the roots or soil though I think
I would do nothing for now and re assess in 3 or 4 weeks

 

The water was just regular tap water out of the hosepipe so it just contains the chemicals they put in drinking water. It wasn't from a water butt and no other chemicals were used for cleaning. Just water.

Is it likely to recover on it's own or do I need to do anything? If it IS salt that's caused it to dry out then wouldn't watering it more be beneficial?

 

Not sure it is box blight but time will tell.....as I said, reassess in 3 or 4 weeks. If its sun scorch it will recover by then.
As ever, feedback would be appreciated

 

Been several days and had a good bit of rain and it's looking worse already. The leaves on top are looking dead and dry.

 

Compared to the others that are planted along the same side which are looking healthy...

 

Wondering if it has anything to do with that hose attachment. Have you checked the soil. Is it it sodden from a leak or dry because its sheltered by the hose reel?

I would brush off the brown leaves and gather them all up and bin them just in case they are harbouring blight. Dont touch the others incase the fungus spreads.wash all tools and hands in very mild bleach soap solution just in case.

 

This has only happened since I pruned it and hosed my path down and watered it. The hose reel has been there for many years and actually is what used to make it flourish. You see, the hose reel has a tendency to drip and so has always kept it slowly and gently watered which is why it's always grown better than the others. I have however noticed that a hole/gap has developed at the back which could indicate that something has been living or burrowing under there. Even so, it's odd that it was doing ok until I cut it and power washed my path.

I'm wondering because of the rain we've had over the last few days and the box now looking worse whether it could be a sign of being overwatered. I never usually water them at all and just allow the rain to do it's job. Maybe washing my path has saturated it and then the extra rain on top made it worse. This may explain why this happened to me before when I washed my patio. I've always been led to believe that box doesn't need much water so maybe it's had too much. What do you think?

 

Just do nothing for now....it will look worse before it gets better
You pruned it, right The Wizard? Then watered it in hot weather? New growth in those circumstances would do just as it has, in my opinion.
Over watering? Well, its only just started showing signs of distress despite a mighty wet winter and early spring so I think not. However, I wouldnt be watering it right now; wouldnt feed it or fiddle with it! In hot dry spells in summer then yes but not now

 

Thanks I'll leave well alone and check back in a week with a quick update.

 

Quick update. One week later. Looking a lot worse now despite not doing anything.

 

Hey! Give it a chance The Wizard. A warm even hot spell coming up in a day or two heralding good growing weather.