FlytrapCare Carnivorous Plant Forums

So I recently set up a vivarium for my tropicals/sub tropicals that like it bright and humid. I have a 4' 4 bulb T8 fixture placed directly over it. However, I want to grow my Australian plants, specifically a tuberous sundew (which I will be receiving this week) under another fixture next to the tank, if possible. I am worried that the light that spills off of the ends of the ends of the light fixture will affect the tuberous sundew's sense of seasons (with a longer photoperiod, from what I understand, it will think it is summer). I ordered a 2' 4 bulb T5HO fixture that will run on a photoperiod of about 8-9 hours (I will reduce it to 7 during the winter hours, unless this is the incorrect thing to do for tuberous sundews. If I am wrong please instruct me).

Since the T5HO fixture is 12" wide, I am hoping that the top of the fixture will sheild the plants directly under it from the light emitting from the T8 fixture, though I suspect that there will still be a bit of light reaching the plants under the T5 fixture. Is this ok? Or will the inderect light still make the tuberous sundew tricked into thinking it is summer.

I have a picture that is the best I could take. Hopefully it helps represent the light currently spilling over. The photoperiod is currently 16 hours on it. All help in deciding whether it would be acceptable to grow tuberous sundews under a smaller fixture below and next to the current one is welcome

Edit: I realized that I forgot to mention that the fixture would (ideally) be to the left of the tank, probably about a foot below the current fixture.

Just that it will get less light and not grow like others do.

roarke wrote:

Just that it will get less light and not grow like others do.

Oh they will get plenty of light, they will be under another fixture. The thing is, the other fixture will turn off much earlier, to simulate an earlier night (winter). However, some light may reach the plants anyways from the fixture above my tank. I am wondering if this inderect light will affect the plant's sense of time.

I'm not sure about the spillover light affecting growth, but you could put foil to block the extra light from reaching it. It'll also reflect some of the original light back into the intended tank making it brighter.

Reducing the photoperiod during winter isn't good. Actually, tuberous Drosera are winter growing plants - and go dormant (well, aestivate) over the summer where it would be hot and dry in their native habitat.

The plant gets cued to start growing mostly by lower temperatures. To keep it growing, the temperature needs to stay quite cool and the photoperiod short (as I'm sure you know). But to go back to a dormant state is triggered by rising photoperiod and temps, simulating the return of the dry season.

w03 wrote:I'm not sure about the spillover light affecting growth, but you could put foil to block the extra light from reaching it. It'll also reflect some of the original light back into the intended tank making it brighter.

Reducing the photoperiod during winter isn't good. Actually, tuberous Drosera are winter growing plants - and go dormant (well, aestivate) over the summer where it would be hot and dry in their native habitat.

The plant gets cued to start growing mostly by lower temperatures. To keep it growing, the temperature needs to stay quite cool and the photoperiod short (as I'm sure you know). But to go back to a dormant state is triggered by rising photoperiod and temps, simulating the return of the dry season.

When I looked up the appropriate length of photo period for tuberous sundews, the common trend for using T5's is to have the photo period be between 7 and 9 hours. However, is this just for supplementing the lack of sun during the winter? Should I maybe have a photo period of 10-12 hours?

It is not supplementing the lack of sun, it is because their life cycle is photoperiod dependent. Long photoperiod is a trigger for the summer phase (regression to tubers) and short photoperiod is needed for active growth. The 7-9 hour photoperiod is so they do not get triggered to go back into the tuber phase.

I recommend looking at this link: http://www.growsundews.com/sundews/Tube ... ndews.html

Keep in mind that since the weather data is from the southern hemisphere, winter is during what we'd consider summer months in the northern hemisphere.

So I want to keep the photo period at about 8 right now, and then reduce it to 7 during winter?

Actually on the site, it says that during march (your winter), the photo period looks to be around 9. Since it is October here, would it be correct to have the T5s run for 9 hours? Should I gradually adjust it as it gets closer to the dead of winter? Also, the temps in my basement during winter stay around 65-72. So under the lights, currently, it should be around 75, which according to the graph is fine for this point in its growing stage.