BRT indoor help with sufficient lighting/watering

Nicobaby

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Hello all I have just purchased my first bonsai (BRT) I’ve had it for 3 days so I’m very new. The tree is about a foot and a half tall in a clay rectangular pot about 12-13 in in diameter.
I have a 4000k full spectrum led 100w light from a grow shop on it for 12 hour light cycles that I’m going to change to 18 now because I don’t think my light is sufficient. Btw I live in US MICHIGAN

My Problem is some of my new growth is yellowing and some leaves have fallen. I don’t think its happy…

My questions are
1. Is 18 hours with a 4000k sufficient if not what kind of light do I need.

2. I’ve been keeping it moist making sure the soil doesn’t dry out I just watered it last night (Tuesday) after i got it Sunday for the first time I didn’t want to overwater.
Does anyone know about how much I should be watering and how often do you just base this off of soil wetness or look more at how the tree is responding.
 
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My questions are
1. Is 18 hours with a 4000k sufficient if not what kind of light do I need.

A 100W LED grow light is probably enough. I recommend having it about 8"-10" from the top of the tree. I only have my lights on for 14 hours and my BRT does fine. 18 hours seems like a lot but may be okay as well.

2. I’ve been keeping it moist making sure the soil doesn’t dry out I just watered it last night (Tuesday) after i got it Sunday for the first time I didn’t want to overwater.
Does anyone know about how much I should be watering and how often do you just base this off of soil wetness or look more at how the tree is responding.

It depends on your soil. I have a BRT prebonsai in a training pot with nursery soil. In that media, it is very easy to gauge watering - I just water when the soil surface just starts to look dry. For me, under lights that is usually 2-3 days. A fast-draining inorganic mix will dry out faster, and may be more difficult to tell. You might be able to tell by feeling the weight of the pot. Some people leave a chopstick in the soil and water right before the submerged end of the chopstick gets dry.

Even if it dropped all its leaves, I would not worry too much. Mine has done that when moved, and I just reduced watering, watched it and eventually new leaves emerged. The one thing that could become a problem is if it has bugs. Watch for sticky residue on or around the tree, webs, or (obviously) little crawly things that don't belong. If you find any of those and don't know what to do, you can snap a photo and ask for advice here.
 

Tums

Shohin
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Hello all I have just purchased my first bonsai (BRT) I’ve had it for 3 days so I’m very new. The tree is about a foot and a half tall in a clay rectangular pot about 12-13 in in diameter.
I have a 4000k full spectrum led 100w light from a grow shop on it for 12 hour light cycles that I’m going to change to 18 now because I don’t think my light is sufficient. Btw I live in US MICHIGAN

My Problem is some of my new growth is yellowing and some leaves have fallen. I don’t think its happy…

My questions are
1. Is 18 hours with a 4000k sufficient if not what kind of light do I need.

2. I’ve been keeping it moist making sure the soil doesn’t dry out I just watered it last night (Tuesday) after i got it Sunday for the first time I didn’t want to overwater.
Does anyone know about how much I should be watering and how often do you just base this off of soil wetness or look more at how the tree is responding.
You can probably get a light meter app on your smartphone to get an idea of how much light the tree is getting.

Rough math time:
Sunlight = ~100k lux, "Full sun" outdoor exposure is considered to be 6-8 hours -> 600-800k "lux-hours" of light energy.
If you have 30k lux from your grow light * 18 hours, that's 540k "lux hours" which is pretty close. But the ultimate "sufficient" amount of light depends on what the tree is telling you, your other care conditions such as temperature, fertilizer, air, water, and your electricity bill. Growing outside during the summer is a lot easier when nature takes care of many of these factors...
 

Nicobaby

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You can probably get a light meter app on your smartphone to get an idea of how much light the tree is getting.

Rough math time:
Sunlight = ~100k lux, "Full sun" outdoor exposure is considered to be 6-8 hours -> 600-800k "lux-hours" of light energy.
If you have 30k lux from your grow light * 18 hours, that's 540k "lux hours" which is pretty close. But the ultimate "sufficient" amount of light depends on what the tree is telling you, your other care conditions such as temperature, fertilizer, air, water, and your electricity bill. Growing outside during the summer is a lot easier when nature takes care of many of these factors...
Bad ass Thankyou!!!
 

Nicobaby

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A 100W LED grow light is probably enough. I recommend having it about 8"-10" from the top of the tree. I only have my lights on for 14 hours and my BRT does fine. 18 hours seems like a lot but may be okay as well.



It depends on your soil. I have a BRT prebonsai in a training pot with nursery soil. In that media, it is very easy to gauge watering - I just water when the soil surface just starts to look dry. For me, under lights that is usually 2-3 days. A fast-draining inorganic mix will dry out faster, and may be more difficult to tell. You might be able to tell by feeling the weight of the pot. Some people leave a chopstick in the soil and water right before the submerged end of the chopstick gets dry.

Even if it dropped all its leaves, I would not worry too much. Mine has done that when moved, and I just reduced watering, watched it and eventually new leaves emerged. The one thing that could become a problem is if it has bugs. Watch for sticky residue on or around the tree, webs, or (obviously) little crawly things that don't belong. If you find any of those and don't know what to do, you can snap a photo and ask for advice here.
Thankyou my friend!!!!
 

Carol 83

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It's not unusual for them to drop some leaves when you change their environment. It will bounce back. I don't have super great lights and mine all do fine inside.
 
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