I'm still experimenting with my HO T-5 fluorescent plant light set up. It really is almost impossible to find any literature about growing tropicals especially Hoyas under them. So I guess it is up to me to report somewhere how these plants are reacting to this type of lighting. They are supposed to be about 2-3 times brighter than conventional T-12 and T-8 fluorescent tubes (the T is the diameter of the bulb; a T-5 is very small - about the diameter of your little finger).
My four tube fixture is about 10-12 inches up from the lowest leaves on the plants. I have around 24 rooted cuttings and small plants under them - three abreast in pots that are 4 to 6 inches in size. I recently moved the light even higher up, because I think the plants may actually be getting too much light. I should also say that the light is on 14 hours per day. All the plants are getting a red/purple tinge to them. They do look healthy, but red. Examples: H. rigida has a cool red border entirely around the edge of the new leaves. H. polystachya has a red border around the leaves with red tinges to the entire leaf and new growth is almost entirely maroon in color. H. memoria has all new growth - leaves and stems red/purple colored. H. australis ssp. Tenuipes all new growth is red/green and totally glossy. H. archiboldiana - all new growth is almost purple. I could list more, but you get the idea.
Does anyone think that these plants are getting too much light? Is it not healthy for them? It is all new territory for me, because I have always felt that I had the opposite problem - not enough light. I recently raised the light up another 2 inches to watch the effect it will have. It seems strange to have the light up that high, because I have been growing seedlings under regular fluorescents off and on for almost 30 years and have kept the lights 4-6 inches above the plants and never had these kind of effects. In the next few days, I will try to snap some pictures to post of these wild colors. Hopefully they will be picked up with the camera.
Doug
Too Much Light?
Don't they normally get a nice red tinge when they are getting enough light? I thought it's the bleached out look that signifies too much on a hoya???
Yes, new growth being maroon in color is a healthy plant. If it was too much, you would get washed out looking yellowish leaves, or burn spots on the leaves (watch for that). Just nice color especially with new growth seems like a GOOD thing.
Marcy
Thanks,
I was hoping the red tinge was a good thing and not a bad thing. This Hoya hobby is still pretty new to me, and I want it to go well.
Doug
Doug,
I haven't had my plants under the lights nearly as long as you have but in the last week I've noticed that all new growth is similar to yours.
What are you doing to keep the fast growing new shoots from reaching up and hitting the hot bulbs? I've had to use some twist ties on several stems because they were growing pretty quickly and getting scorched as they hit the bulbs. I'm considering using a net of some sort to hold the new growth in place but I know it will be a pain in the backside when I have to untangle it all and start cutting the intertwined plants out of the net at the end of the winter.
Sounds like things are growing marvelous underneath your lights. I had mine growing under lights last winter and they were all getting really pretty red new growth. Sounds like your conditions are fine.
Mulletman, I was having the same problem with some of my stems hitting the lights. The taller one's I moved to the bottom shelf and lifted the light as it gave them a little more room. I also just looped them with the growing point pointed up and clipped the stem together with a bee clip. Does that make since?
Mulletman,
I had to move the one plant that was going to grab the bulb at all costs (H. magnifica) to a new pot, and I put it on a windowsill. You are right about these lights being significantly hotter that regular fluorescents. There is no doubt that they would burn the plant if the plant even gets within an inch of the bulb. I would be afraid to use the netting idea for the very reason you gave; it would be a bear to untangle that mess in the end. I think I would use Tami's idea of clipping them to themselves or put small wire trellises or loops into each pot (like Carol sells) and clip it to that. With my mylar room set up, it is a little easier, because I have a lot of latitude as to how high I can raise the lights from the shelf. I could raise them 3 feet above the shelf if I needed to. In another area where I am using these lights as supplemental lights over a window; I have the same problem you are experiencing, and have to stay really vigilant, and keep those vines clipped down.
I'm happy that we are having the same experience with the coloration of the plants, and that the consensus is that it is a good thing.
Doug