Any hope for saving this cotoneaster horizontalis?

[mtjzm]

Hello,

I gave my partner a cotoneaster horizontalis, from a bonsai nursery, for her birthday in early April. About a month later, some leaves started turning yellow. She thought she didn't water correctly, but that now turned out was not the source of the problem. Unfortunately, we went on vacation. When we came back yesterday we found the tree without any green leaves and with many tiny, white "sticks" on it. (See the photos.) It is probably some kind of mite? I treated the bonsai with spider mite spray yesterday. However, when I looked at the plant again today, I saw a somewhat bigger—yet still tiny (about 1/8 inch)—white insect crawling around as well. So maybe these tine white "sticks" are larvae?

I have little hope that the bonsai could become healthy again, but maybe there is a tiny chance for it? Any help would be very much appreciated.

 

[WNC Bonsai]

First mistake, you were keeping it inside—death sentence. It needs to be outside in zones 5-7. So you went on vacation and left it to water itself? The white “sticks” look like dead bugs. If you don’t have a yard or balcony then get cacti or other succulents for your bonsi efforts.

 

[mtjzm]

The person at the bonsai nursery said it could work inside if very light. We have no yard or balcony. (Yet we have many plants that are not cacti or succulents. Thanks for the very friendly advice...) I thought it wouldn't be necessary to say that, but the bonsai was of course watered while we were on vacation. Any help regarding the question what the exactly white "sticks" are (if they are bugs, what bugs?) would be much appreciated.

 

[Esolin]

Welcome to bonsai Nut! The white sticks are bugs ( I don't know they're name, but they're similar to aphids I think), but I don't think they caused your tree's demise, they were just opportunists that piled onto a suffering tree. I killed my first bonsai tree by keeping it indoors. I thought they were just another type of house plant. Yes there are a lot of house plants that survive indoors just fine, but they tend to be tropicals with very large leaves to soak up every speck of light. Preferable species for bonsai have small leaves so that they give the illusion of small trees. While I have heard of some elms surviving inside, better indoor bonsai candidates with small leaves are various succulent and ficus plants. If you wish to keep other sorts of species alive inside, you'll have to use grow lights and other such things to give them the environmental conditions they need. Even then, this gets tricky and requires a lot of fine tuning depending on the species.

It's possible your tree is still alive. Performing a scratch test on the bark is the best way to tell. If you make a small scratch and see green under the bark, there's still life in the tree. If it's brown and dry under the bark, it's dead. But even it it's alive, without a balcony were it can get some fresh air and direct sunlight, it's unlikely to recover.

 

[SeanS]

The person at the bonsai nursery said it could work inside if very light.

Although we’d all like to believe that all bonsai nurseries have the best interest of their customers and trees at the forefront of their minds, many are just operating as businesses and want to make sales. They will tell you that most plants they sell will do fine indoors in order to make a sale. In reality this is not the case.

 

[mtjzm]

Welcome to bonsai Nut! The white sticks are bugs ( I don't know they're name, but they're similar to aphids I think), but I don't think they caused your tree's demise, they were just opportunists that piled onto a suffering tree. I killed my first bonsai tree by keeping it indoors. I thought they were just another type of house plant. Yes there are a lot of house plants that survive indoors just fine, but they tend to be tropicals with very large leaves to soak up every speck of light. Preferable species for bonsai have small leaves so that they give the illusion of small trees. While I have heard of some elms surviving inside, better indoor bonsai candidates with small leaves are various succulent and ficus plants. If you wish to keep other sorts of species alive inside, you'll have to use grow lights and other such things to give them the environmental conditions they need. Even then, this gets tricky and requires a lot of fine tuning depending on the species.

It's possible your tree is still alive. Performing a scratch test on the bark is the best way to tell. If you make a small scratch and see green under the bark, there's still life in the tree. If it's brown and dry under the bark, it's dead. But even it it's alive, without a balcony were it can get some fresh air and direct sunlight, it's unlikely to recover.

Thanks for the welcome and for the explanation. This is helpful. It turns out that the bonsai was probably even moved to a less sunny spot in order to make things easier for the person who came to water the plants. That is very sad.
We have some windows with a lot of southern California sun—so much that other plants get scorched. But that couldn't possibly make a cotoneaster horizontalis survive inside, it seems?

@SeanS: I was wondering. The vendor was initially telling me that the bonsai has to be outside and only then did I say that we have no possibility to put it outside and if it might possibly work inside. He could have been more clear had he wanted to be perfectly honest, but he may have only said that it can or could work inside.

 

[Shibui]

The pictures are not quite close enough to get a good ID on the white bugs but they look like thrips from this distance. Can be difficult to control but a systemic insecticide may do it. Miticide probably won't be effective on insects. I suspect it is too late to use a systemic on this tree ( see below). See if you can find any contact insecticides that treat thrip. There's still a very faint chance the tree is still alive under all those dead leaves. If you can stand having a dead tree for a few more months you may like to continue care for a few more months, cross fingers and toes and hope that it comes back.
Unfortunately many plant pests love indoor conditions and are probably another reason why so many plants don't do well indoors.

The photos do show wrinkled bark which generally indicates the tree is dead and probably has been for some time. A lot of plants can stay green using the reserves of food and energy in the trunk, sometimes for months after the roots have died. This can make it troublesome for beginners to accurately pinpoint time and cause of death. Most likely cause will be watering but could be too much or not enough. Symptoms are similar for both but the end result in the same in both cases.

We have some windows with a lot of southern California sun—so much that other plants get scorched. But that couldn't possibly make a cotoneaster horizontalis survive inside, it seems?

Light is only one factor in tree growth and health. Air flow, humidity, seasonal temperature differences, pests and other factors also come into play. The plants that do tend to do well indoors tend to be species from tropical and sub- tropical rainforests which are adapted to low light, low air movement, relatively stable seasonal temps and periods of low humidity and rainfall.
A lot of people have tried temperate species indoors and very few have succeeded. There are legions of threads here almost identical to yours where unsuspecting newbies have been sold temperate species and told they can/may do well in a bright sunny indoor spot.

 

[Paradox]

The person at the bonsai nursery said it could work inside if very light. We have no yard or balcony. (Yet we have many plants that are not cacti or succulents.

Your best option for indoor only bonsai is a ficus.

 

[mtjzm]

Thanks for all your replies. This is very helpful. (And thanks for continuing to help unassuming newbies!)

 

[WNC Bonsai]

Thanks for all your replies. This is very helpful. (And thanks for continuing to help unassuming newbies!)

Unfortunately this is all too common, with eager beginners being misled by folks anxious to make a sale. Good lick with fonding another tree that will work for you in your apartment.