Fluorescent Lighting, and
Flood and Drain Timing

I have a hydroponic system for my garden and I'm using fluorescent lighting. I know it's not the best, but it's best for my light bill and I've heard its fine in the beginning stages (HPS lights are best in flowering stages). How can I simulate Autumn sunlight without having to purchase high pressure sodium fixtures or Metal Halide?

Also, how often should I flood and drain the nutrient solution in a day with an ebb and flow system? Thanks.

Answer: Fluorescent lights are fine to use on seedlings, clones, and in the vegetative stage....as long as you keep them close and as long as your plants are shorter than 15 inches tall. Past that, the light is not intense enough to support healthy growth. If you try to use regular fluorescent lights to flower your plants, you are likely to be very disappointed with how much produce you get for all your efforts. With that said....

Whenever using fluorescent lights, always buy the bulbs with the largest number of lumens on the box (this is a measure of usable light to the plants). Fluorescent lights called "cool white" or "cool" will have more blue, and therefor would be better for the veg stage. Lights marketed as "warm" contain more red spectrum light, which is more beneficial to flowering (like Autumn light). In reality, this makes little difference when using fluorescents because the light is not intense enough in the first place.

The most affordable lighting solutions with a little more "kick" (for flowering) would be- One, a compact fluorescent light. Two, T5 fluorescent lights (also known as Tek lights). Three, a small HPS light. Once you are dealing with this stronger group of lights, having more red light in the spectrum may actually provide the benefit it is supposed to.

If you only have a small garden, you can get away with a smaller HPS light. Do a search on the internet for "HPS security light"....you may be surprised how affordable some of them are. I found one 150 watt model for $39.00! If you only use it for flowering (12 hours on per day) the cost in electric shouldn't be that bad at all (less than $10 a month I would guess). You can also find these type of security lights at Lowes, Home Depot, and maybe even Wal-Mart.

T5 light fixtures can be a little expensive (but you only need to buy the light fixture once). They are pretty easy on the electric bill, and produce results comparable to a small HPS.

If you buy a compact fluorescent (the kind with very high lumens and a light reflector hood), you will spend more than you would for the HPS light, but slighly less than you would for a 4 bulb T5 light. Compact fluorescent lights (the kind made just for indoor gardening) are easy on the electric bill, and pretty comparable to the other two lights as far as the results go.

Try to find out how many lumens each light produces before you buy one. This is how much usable light it is going to produce. When you go to set up the garden, however, you want to use the number of watts to figure out how big of a garden space you can have. Flowering plants that love light should be given about 40 watts per square foot of the garden as a minimum. If you want results, try to make it your goal to hit this number. Read over my grow light selector page. It contains some math that will help you figure out the proper garden size for whichever light you end up choosing.

Finally, you will probably want a short cycle timer, or hydro-timer, to control your flood and drain pump. How you run the flood and drain schedule depends on what kind of grow medium you are using in your hydroponic system. Rockwool absorbs lots of water quickly, than tends to hang onto it. Clay pellets, on the other hand, need to soak for about 20 minutes to absorb the proper amount of moisture, and than they drain fairly quickly.

If using a medium like rockwool (or coconut coir), I suggest flooding the table for just a couple of minutes once or twice a day. If using clay pellets, flood them for about 20 minutes perhaps four to six times a day. In the end, you will want to keep an eye on the medium and on your plants and fine tune your irrigation schedule if your plants look like they need more frequent or less frequent irrigation (but that should be a good place to start). I hope this helps, and Happy Growing!

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Flood and Drain Timing

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Apr 06, 2010
LED lighting
by: Anonymous

LEDs have come a long way and are much cheaper than any form of fluorescent. I recently picked up this unit - 112 watts with the equivalent output of a 250W HID. Runs very quietly and produces very little heat.

Added response: The bottom line is results. If you don't mind terribly, I would be very interested in your garden size and your yields (this goes for anyone using LED lights exclusively).

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(10 week update below)

Find out the cheapest and easiest ways to garden productively in this article.

Hi everyone, Jason from Jason's Indoor Guide here. When I got started with hydroponic gardening more than 24 years ago, my first garden used rockwool cubes and B.C. Nutrients....and I remember thinking to myself yeah, sure, there may be a lot of advantages to gardening with hydroponics, for example there are very few pest problems, therefore very little pest control, no weeding, no plowing or tilling the soil, no soil testing or having to add things into the garden soil, no watering the garden....but for someone who just wants to grow their own vegetables and have more control over their food supply and the quality of the food that they eat, the cost of constantly having to buy grow media and hydroponic nutrients makes this an expensive hobby for most people...

Epic Nutrient Change

I suppose when you take into consideration how much money you save NOT having to buy food at the grocery store, it is surely cheaper to grow your own food hydroponically even with the cost of high quality nutrients. Nevertheless, I didn't have a whole lot of money to work with and I needed to make my efforts as affordable and effective as possible....and in the last 24 years I HAVE learned a thing or two!

As you browse through Jason's Indoor Guide, you will notice all of the systems that I use personally are homemade systems. As I got 3 or 4 years of experience under my belt, I quickly adopted a preference to standing water systems and systems that use expanded clay pellets or lava rock, because the media is re-usable and it eliminates a huge operating expense. So once a hydroponic system is built, garden maintenance is minimal- check and adjust the nutrient solution daily, and to change it completely every 2 weeks....and the biggest operating cost is the hydroponic nutrients. (and the electric bill, lol)...

Homemade Cloner

And, regarding the cost of the nutrients....I experimented for about 3 years with making different compost teas and nutrient teas, but there is still a lot of expense $$$ associated with making high quality nutrient teas....like kelp meal, liquid seaweed, rock dust, bat guano, un-Sulfured molasses, worm castings. You can eliminate a lot of this expense by becoming an expert at making high-quality colloidal humus compost, and use your properly made compost as the basis of your hydroponic nutrient solution.

Unfortunately, I have been gardening for over 24 years and I have only just recently mastered this difficult skill....and even then, only because I happened to find a very easy to follow, high quality technique and decided to follow the instructions to the letter. I produced more high quality compost in just one week than I was able to use in a whole year! If you can master the technique, I highly recommend it. It is one of the top 3 things you can do to increase the productivity of your food production efforts, while at the same time decreasing the amount of effort required to grow all of your own food, and decreasing the total cost of operating your food production system.

And when I say decrease operating costs, I mean decrease them to almost ZERO, especially if you are producing your own nutrients...

High Efficiency

The ultimate solution to eliminate the cost of your hydroponic nutrients: Imagine a hydroponic system that does not require you to buy any nutrients, does not require you to make your own compost, and does not require you to brew your own nutrient tea. Seriously! No cost and no effort as far as providing nutrients to your plants! Plus, at the end of the gardening cycle you harvest all of your garden vegetables, PLUS YOU HARVEST FISH from the system--->


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This solution is aquaponics. If you are serious about producing all of your own food and being self-sufficient, this is the ultimate solution for reducing expenses (as much as possible), reducing the total amount of work required, and maximizing the productivity of your gardening efforts. I have been gardening for over 24 years, and it is the perfect food production solution in my opinion.

Produce garnden vegetables AND fish together. Eliminate fertilizer costs!

Besides mastering how to make high quality compost, learning aquaponics is one of the top 3 things you can do to increase your garden productivity, reduce your total costs, and reduce your total work. The product that I learned from is called Aquaponics4you. With all of my hydroponic gardening experience, the first time I came across the Aquaponics4you product I knew immediately that it was something very special! Place an aquaponics system outdoors and use the sun instead of grow lights, and you have reduced every garden expense to nearly ZERO!

The Same System/ 10 Weeks Later!

If you've found this site helpful at all, I would really appreciate it