HELP with my Grape Bonsai!!

[chefmateo]

I have a nice grape vine bonsai that had been killing it all summer! Throwing of a little fruit also. In a matter of under 72 hrs, it shriveled up, dropped leaves, the ones still on the canes were dry & crispy. I don't over water it & it gets a full 8 hrs of sun a day. What could possibly make something decline so rapidly? I checked for pests & found none. I didn't notice any white mildew or any other discolorations either. I have trimmed off all the dead stuff & pulled into a semi shaded ICU area for now. I'm hoping it'll bounce back, but also looking for any suggestions on possible remedies. Thanks.

I posted some current pics & ones when it was healthy.

 

[chefmateo]

Update: I posed this question to the seller of my grape. They suggested removing half of the soil & washing the roots thoroughly..then replace the other half with fresh soil. I hate to re-pot an already stressed plant, but if the illness is associated with the roots, then this seems like a logical remedy..albeit a risky one. Any opinions? Thank you.

 

[Wires_Guy_wires]

If the illness is associated with the roots, then I'd say washing the soil away wouldn't help much. I mean, if it's an infection, it's already inside the plant and you can't really wash it out. Systemic biocides are needed to treat that, possibly rendering your fruits inedible for at least a year.
I have owned grapes as long as I can remember, but this is the first time I'm seeing something like this. Ours has a raging fungal infection on the deadwood, but it's not damaging live tissue or anything in the past 4 years.

I don't know the Dallas weather or climate, but over here we're starting fall. Due to lower temperatures our grapes get really cool colors. I don't know if that happens in TX as well, since 'low temperatures' are my 'high temperatures'. It could just be fall dormancy, but then I'd expect the plant to at least drain the foliage of remaining nutrients. Unless there's been a really cold snap, when temperatures drop rapidly to freezing, the plant can just reject foliage by abscission in a matter of hours. This sudden dieback could be Eutypa, but that usually comes in stages and it'll be visible in a trunk with that little shoots.

Can you tell us a little more about what you did with it in the past few months? Are there vineyards nearby? That might give some pointers on where to look. You can pretty safely remove the bark strips by the way, it helps prevent scale and mite infections and it might show you a little more of what's going on. They'll be back next season if the tree survives. Remove those strips as you would clean a juniper; don't go into the live tissue. Grapes are way easier to clean compared to junipers.

 

[chefmateo]

If the illness is associated with the roots, then I'd say washing the soil away wouldn't help much. I mean, if it's an infection, it's already inside the plant and you can't really wash it out. Systemic biocides are needed to treat that, possibly rendering your fruits inedible for at least a year.
I have owned grapes as long as I can remember, but this is the first time I'm seeing something like this. Ours has a raging fungal infection on the deadwood, but it's not damaging live tissue or anything in the past 4 years.

I don't know the Dallas weather or climate, but over here we're starting fall. Due to lower temperatures our grapes get really cool colors. I don't know if that happens in TX as well, since 'low temperatures' are my 'high temperatures'. It could just be fall dormancy, but then I'd expect the plant to at least drain the foliage of remaining nutrients. Unless there's been a really cold snap, when temperatures drop rapidly to freezing, the plant can just reject foliage by abscission in a matter of hours. This sudden dieback could be Eutypa, but that usually comes in stages and it'll be visible in a trunk with that little shoots.

Can you tell us a little more about what you did with it in the past few months? Are there vineyards nearby? That might give some pointers on where to look. You can pretty safely remove the bark strips by the way, it helps prevent scale and mite infections and it might show you a little more of what's going on. They'll be back next season if the tree survives. Remove those strips as you would clean a juniper; don't go into the live tissue. Grapes are way easier to clean compared to junipers.

Since spring after a repot, I've simply been watering it as needed after a soil check. Trying not to over water. Fertilizing once every 3-4 weeks. I use Super Thrive & fish emulsion as my two choices. It's on a bench in full sun a minimum of 8 hrs a day next to my bougainvilleas & desert roses. There are no vineyards within 30-40 miles of me. It turned for the worse almost overnight on this past Sat 9/7. Sun & Mon it's just continued to wilt & get worse. Temps around here are still over 95 degrees & will remain well over 90 until late September early October. We get about 2-3 weeks of fall in mid to late Nov & sub 45 degree weather is mid to late Dec-Jan.

 

[CasAH]

Has there been anyone spraying herbicides in your neighborhood? Grape vines are very sensitive to herbicides.

We had a person in Chicago have most of his collections over 100 trees wiped out when his neighbor spread Roundup on a windy day. State investigated said it was herbicide poisoning, but cannot prove it was the neighbor’s actions, police dropped it.

 

[cbroad]

@CasAH
I was going to ask the same thing.

Also, any chance lawn people were there or at the neighbor's spraying chemicals or fertilizer?

 

[Carol 83]

Has there been anyone spraying herbicides in your neighborhood? Grape vines are very sensitive to herbicides.

We had a person in Chicago have most of his collections over 100 trees wiped out when his neighbor spread Roundup on a windy day. State investigated said it was herbicide poisoning, but cannot prove it was the neighbor’s actions, police dropped it.

I work for an agricultural co-op. During spray season, wind speed has to be recorded on every spray ticket, and no spraying is allowed when it is windy. Damage claims can be very expensive. It is a real shame that the neighbor was not held responsible for the loss.

 

[chefmateo]

No pesticides as far I know. I re-potted & washed the roots thoroughly on Wed. I didn't see any rot or significant issues there. I replaced the soil with a pumace base, then my usual bonsai mix. It's watered in & now under my porch which gets about 4-5 hours of sunlight evenly split with early morning rays & the evening setting rays. Fingers crossed & prayers said, & hopefully it makes a recovery. What green remained after my initial hard pruning is still viable & soft.

 

[chefmateo]

4 days later & I have new growth!!! Hope to get some good continued vigor for a couple more months before dormancy. Looks like so far, the seller was right in offering the root wash/soil change suggestion. Only time will tell. Still .

 

[Sn0W]

I have 4 beasts and they have all done the same. I think my problem was I let them get too dry. They've just started pushing buds so I'm hoping they can get leaves and gain some energy before they need to go dormant

 

[chefmateo]

Mine were watered regularly..probably a tad more over than under considering the 100+ degree heat we consistently endure here with Dallas summers. When I did the initial examination & hard prune it was fine with regards to moisture. Not sure what happened & not sure why the soil change per the seller's recommendation seems to have so far made positive gains for it either. Head scratcher for sure.

 

[Sn0W]

Maybe it was over watering. Mine are still in the soil they came in and I don't know how it drains. I was waiting until spring to repot into some decent substrate but now I'm questioning if I should do it now or not.

 

[chefmateo]

Maybe it was over watering. Mine are still in the soil they came in and I don't know how it drains. I was waiting until spring to repot into some decent substrate but now I'm questioning if I should do it now or not.

Maybe so, but I don't see how. I check with a chopstick & even skip certain plants due to the fear of overwatering. My grapevine, Ashe Junipers, Bougainvilleas, & desert roses, I specifically skip consecutive days of watering. All my other bonsai & tropicals get doused twice a day. I have a Brazilian rain tree that I place the pot into a Christmas tree stand, so that it has water on it as much as possible. In this Dallas heat it's dried up in two days easily. Anyway..the grape is rebounding nicely, & we won't get a sniff of cooler weather until maybe early to mid November, so it's got time to get some good growth in. Debating whether to fertilize it one last time with some fish emulsion.

 

[parhamr]

Washing out half of the soil from an unhealthy tree seems like such a suspect recommendation. I’m glad it didn’t make things worse!

If the illness is associated with the roots, then I'd say washing the soil away wouldn't help much. I mean, if it's an infection, it's already inside the plant and you can't really wash it out. Systemic biocides are needed to treat that, possibly rendering your fruits inedible for at least a year.
I have owned grapes as long as I can remember, but this is the first time I'm seeing something like this. Ours has a raging fungal infection on the deadwood, but it's not damaging live tissue or anything in the past 4 years.

I don't know the Dallas weather or climate, but over here we're starting fall. Due to lower temperatures our grapes get really cool colors. I don't know if that happens in TX as well, since 'low temperatures' are my 'high temperatures'. It could just be fall dormancy, but then I'd expect the plant to at least drain the foliage of remaining nutrients. Unless there's been a really cold snap, when temperatures drop rapidly to freezing, the plant can just reject foliage by abscission in a matter of hours. This sudden dieback could be Eutypa, but that usually comes in stages and it'll be visible in a trunk with that little shoots.

Can you tell us a little more about what you did with it in the past few months? Are there vineyards nearby? That might give some pointers on where to look. You can pretty safely remove the bark strips by the way, it helps prevent scale and mite infections and it might show you a little more of what's going on. They'll be back next season if the tree survives. Remove those strips as you would clean a juniper; don't go into the live tissue. Grapes are way easier to clean compared to junipers.

This is a really detailed and thoughtful answer! Well done.

 

[Wires_Guy_wires]

Reading back all this, I think suffocation of the roots is a very likely suspect. I mean, they're originating from the desert.
Our grapevine didn't flinch this year when we went without rain for over two months.
As a matter of fact, this has been one of the best years for our largest grapevine. Around a bucket full of grapes per two foot of vine. And this is Northern Europe, not France or Italy.

 

[chefmateo]

One week later & all is well. Filling out nicely.