Greenhouse Lighting

hi! i'm pretty new...we built our greenhouse in april. i'm doing raised beds and so far have been pretty successful. we've had some nights in the 20s here in knoxville, tn and the greenhouse hasn't gotten below 45 with just a portable radiator heater and a heat lamp, and it heats up nicely during the day. its connected to the house on two sides which helps...but the days are way shorter. i'm still getting tons of flowers on the tomatoes and peppers, but its taking forever for things to ripen up and things have slowed down some. i figure i need to supplement light. i have two 4' fluorescent lights out there right now that don't really do much and i'm looking at maybe getting a couple of t5 HO fixtures.

i'm looking at something like this: http://www.amazon.com/Light-6lamps-DL846S-Fluorescent-Hydroponic/dp/B00NMYLOBU/ref=sr_1_10?s=lawn-garden&ie=UTF8&qid=1417899987&sr=1-10&keywords=48+t5+ho

or this: http://www.homedepot.com/p/ViaVolt-4-ft-4-Bulb-T5-High-Output-Copper-Fluorescent-Grow-Light-Fixture-V44/203012866

i want the best light i can get at the lowest cost.

thoughts?

I like those lamps but I don't know the dimensions of your greenhouse. Also, you probably are going to need more heat, perhaps an inexpensive electric heater with a small fan or box fan beside or behind to dissipate the heat. I have two heaters in each of my two greenhouses and two in my enclosed porch but, because I grow tropical plants, I keep my structures around a minimum of 55 F.

Ken

thanks for the help! the greenhouse is about 30 feet long by 12 wide.

i have another heater...you can see it in the background of the pic with the lettuce. its actually a heater/air conditioner/dehumidifier that has a blower. i found it at a thrift store for $35 (same brand, etc as this one but older: http://www.homedepot.com/p/Soleus-Air-13-000-BTU-Portable-Air-Conditioner-with-Dehumidifier-Heat-and-Remote-PH5-13R-35S/202042119 ). i lucked out...the thrift store thought it was an air purifier. i can use it, but i need to vent it outside...it blows a lot of cold air out the back when the heat is running...which isn't very helpful!

the plan was to grow cooler temp veg in the winter, but the tomatoes and peppers are still doing really well. i have broc and cauliflower and brussel sprouts that i'm tried to start in my little hydroponic set up, but i'm not seeing anything yet. beginning to wonder if maybe the water is too cold...or maybe the seeds fell through the clay pellets.

so, i think i may go with the lights on amazon. there are two options of bulbs: F54T5HO 6,500 kelvin white grow lamps or i can request 3000k bloom bulb

any thought on which would do better? i plan on growing mostly veggies. thanks!

Personally, I would go with the upper range of K. But if you have a choice and can mix those tubes, get a lamp with four 6500K and two 3000K tubes. Or, depending on how many fixtures you are buying, purchase two with the 6500K and one with the 3000K and then just mix the tubes yourself. That number could be multiplied by 2 or 4 with your huge GH. Choices, choices, choices!

Ken

great advice...that's what i'll do. do you think the HO T5s will make a big difference? do you think the lack of light is why its taking the tomatoes forever to ripen?

The HO lamps produce almost twice the light as a standard T5 and have higher wattage. Since the angle of the sun is now reduced, there is a great reduction in light afforded and there are less hours of daylight as well. Those HO lamps should make a big difference. I am no expert on vegetables (tropical plants are my thing), but I would guess that those HO lamps will help ripen your tomatoes. I have my florescent lamps turn on around 3:00 PM and turn off around 9:00 PM. I am not only adding more light when the afternoon light begins to diminish but also increasing the hours of "daylight". But regardless, be sure to tell everyone what the outcome is. That's how we all learn.

Ken

great, thanks for the help...i'll post results. i'll probably order them tomorrow...

thanks again!

I ordered two of those yesterday and they shipped out today. You pointed me to a lamp I had never used and now I want to see if these will ultimately replace my T5 florescent fixtures.

We can both post our results - you for vegetables and me for tropical (most orchids).

Ken

I haven't had much luck germinating seeds in my hydroponic setups, I germinate in potting soil in 4 inch pots and when the roots are too big I place the pots in the hydroponic setup and let the roots grow out the bottom and spread. I'm using a couple of HO T5 fixtures that were intended for aquariums, seem to be doing ok

The orchid growers in my area suggest the cheap curly florescent lightbulbs. Anything over 5000k will do it. It doesn't matter whether they are day light or natural light or... Just so they are over 5000k.