First Bonsai- Gardenia

[RMEddins]

After a couple years of researching bonsai (and collecting bonsai material locally here in the rural outskirts of Memphis) I finally decided to order a bonsai. I selected a Gardenia. It arrived about 2 months ago. The plant is putting on new growth and all is going well. The weather is cooling down here now, and I'm curious as to what steps I need to take in order to keep the plant healthy. I have been keeping it outdoors, but I've got a 1000 watt Metal Halide grow light if wintering the Gardenia indoors is advisable. Any tips will be appreciated.

 

[Leo in N E Illinois]

There is wide variation in how hardy different gardenia species and hybrids are. Some are fairly tender sub-tropicals. Some are fully hardy through zone 7, which would include Memphis. If you bought it at a local landscape nursery as outdoor material, it probably is hardy. If it was mail order or from a florist, it may be more tropical. Do you have a species and or cultivar name?

 

[Leo in N E Illinois]

I did a little bit of reading. Wikipedia page for gardenia is helpful. The page on Gardenia jasmoides lists about 6 cultivars that would be hardy in Memphis. If you don't have a cultivar name, assume it will not tolerate a hard freeze.

 

[Leo in N E Illinois]

I like gardenia as bonsai. They like an acidic soil much like azalea. Moderately easy to grow, if you get the soil right.

 

[RMEddins]

Thank you, for the quick response. The tree was ordered online from Bonsai Outlet. There is no mention of cultivar at all on the website or on any of the emails they sent me with transaction details. However, when searching for cultivar on Bonsai Outlet, I found their "Gardenia Care Guide". The type they're selling, and I now own, definitely can't handle the cold temps. It says when temp gets below 50, it's advisable to bring inside and provide as much light as possible.

If anyone has knowledge of metal halide and/or T5 Flourescent lights as it relates to bonsai; I have a question. How many hours of lighting should I provide daily? How close should the bonsai be to the light?

Do Gardenia go dormant? If so, how do I trigger dormancy when the plant is indoors? ...dark closet possibly?

 

[cbroad]

If anyone has knowledge of metal halide and/or T5 Flourescent lights as it relates to bonsai; I have a question. How many hours of lighting should I provide daily? How close should the bonsai be to the light?

Typical light timing is 18 hours on and 6 hours off, or if you want to save a couple dollars you can do 16 hours on and 8 hours off.

If you're using a t5, as close as possible to the top of the plant, maybe a couple inches to be on the safe side so you don't burn the foliage when it grows toward the light.

If you're going to use the 1000w, at least a foot from the light, if not as much as 2 feet.

Some dormancy should be given to most plants, but we can usually get away without giving a dormancy for subtropicals and tropicals.

FYI, as far as gardenia's are concerned (living exclusively outside) in borderline areas (zone 6-7) and if you plan on getting more that are temperate, it's definitely a good idea to protect the root systems. Potted plants usually lose a zone, so a zone 7 plant in a pot should be considered a zone 6 plant.

 

[cbroad]

Do Gardenia go dormant? If so, how do I trigger dormancy when the plant is indoors? ...dark closet possibly?

Usually the photoperiod dictates when a plant starts going dormant, and lower temperatures to some extent. You could set your light for 12 hours on and 12 hours off, but I'm not sure if that's really a good idea.

Really, you should be decreasing the light by about a minute everyday after the summer solstice, but that kind of complication isn't really necessary. Not exactly scientific but it gives you an idea of what's needed to induce true dormancy.

 

[RMEddins]

Cbroad, thank you so much for the info. I haven't been able to find reliable info on this subject anywhere. As gracious as I am, I'm going to trouble you with another question. Do you have any advice on a book/website, anything I could acquire with good info on photoperiods & manipulating dormancy? Also id like to get some material on indoor lighting (hours per day, maximizing lumens, etc.) I noticed you were a horticulturist so I thought you could possibly point me in the right direction.

Update: So I literally just noticed you're a certified "hortitorturist". Lol, Either way hopefully you can help

Regards,
Michael Eddins

 

[Leo in N E Illinois]

Most gardenia are sub-tropicals, the dormancy required is short. No need to do increment changes in photoperiod. If you grow it outside until September or early October, beginning Sept 22 it will get less than 12 hours of light. Count the number of weeks it got of short day length, the figure to keep the lights on 10 or 11 hours for enough weeks to total 12 weeks. Then crank up the light to 18 hours on, 6 hours darkness. The gardenia should respond by acting like it is springtime. G. jasmoides can bloom off and on much of the year. The older the bush the more frequently it will bloom.

 

[cbroad]

Hahaha, I am a certified horticulturist too, or at least I was...

Do you have any advice on a book/website, anything I could acquire with good info on photoperiods & manipulating dormancy?

No, unfortunately I don't... A lot of this information is species specific so there really isn't much information that I have past "general" plant care.

Plants usually have a threshold of what they'll tolerate, so we experiment within those constraints, and there are so many variables at play, that nailing down a complete and definite plan can be hard.

The indoor pot growers have made huge strides for indoor growing. Their business is all about tweaking photoperiods, not wasting lumens, and maximizing yields, so you can find all sorts of info on those topics. In the meantime we can try to help you here with any questions!

 

[cbroad]

A lot of this information is species specific

Think about the area that whatever plant is native to, this will give you an idea of what constraints you have to work within, like amount of dormancy needed (if any), humidity, light exposure, etc. Then try to replicate that, or get as close as possible given your circumstances.

If you're going to use the 1000w, at least a foot from the light, if not as much as 2 feet.

That's the on the most extreme end of the spectrum, you may need more distance than that. I don't want you to blast your gardenia