FAQs – Lighting
- Q. Which is a better lamp to grow with MH or HPS; I’m on a limited budget and can only afford one?
A. I would recommend purchasing the Metal Halide kit, and when it comes into the bloom stage you purchase an HPS conversion lamp or a full spectrum MH lamp. If you are only going to use one type of bulb for flowering and vegetative stages the Sun Master neutral deluxe is an excellent lamp for both purposes. This will be more economical for setting up on a limited budget.
- Q. How long does the average 1000 watt HPS lamp last?
A. On average they burn for 12000 hrs but most gardeners replace once a year more maximum efficiency from the lamp. The cost of new bulbs is minor in comparison to yield loss from weakened lamps. The best way to monitor a bulbs wear is with a light meter. These can be expensive, any where from $100-$300, but for a larger scale set up it is wise investment.
- Q. Is it worth the investment to upgrade to a full spectrum bulb rather than the standard bulbs?
A. While the standard bulbs perform very well, I have seen first hand the benefit of full spectrum lamps such as Hortilux, Solarmax and Sunmaster and can say with confidence these lamps are definitely worth every penny. But if you are on a limited budget and you buy the clears you will still get excellent results as they are still a very high quality lamp. The full spectrum bulbs give you a combination of red and blue light similar to HPS and MH mixed together which is best for optimum growth.
- Q. Which Bulb should be used in the Vegetative stage and which one in the bloom?
A. Use a Lamp with a high output in the blue range of the spectrum for the vegetative stage and for the flowering stage use a lamp with a high out put in the red range of the spectrum. During all stages of growth but especially during the bloom stage plants require a balanced mix of blue and red for optimal growth.
- Q. Based on Lumen per watt Ratio what is more efficient to operate, MH or HPS?
A. HPS gives a higher lumen per watt ratio than metal halide and the bulbs often last up to twice as long. The 600 watt HPS has the highest lumen per watt ratio of any HID bulb. But for growing MH has a higher PAR value than HPS but often isn’t enough in the red range of the spectrum, this is why a mix of both is required for optimal growth. Or the use of full spectrum bulbs is replacing mixing the MH with the HPS. The bulb manufacturers are doing this for you.
- Q. Can I run a 1000 watt MH bulb wired up to a socket and just plug it in my wall plug?
A. Absolutely NO, NO and NO!!! You have to use a 1000 watt MH ballast to power this lamp. The power coming out of your wall must be transformed to usable voltage by the lamp. This is the job of the ballast.
- Q. What should my light cycle be for growing indoors?
A. Since plants all have a different requirement of light that will depend one what type of plants you intend to grow. The best thing to do would be research the plant you wish to grow and find out its light requirements. Most gardeners use an 18 hours of light, 6 hours in the dark cycle for the vegetative stage and a 12 hours of light, 12 hours of the dark cycle for the blooming stage.
- Q. What is a Lumen?
A. A lumen is a measurement of light. In simpler terms one lumen is equal to the amount of light that 1 candle will emit on 1 square foot, 1 foot away from the flame. 1 lumen = 1 foot candle
- Q. What is Lux mean?
A. Lux is the metric unit equal to the amount of light falling on one square meter 1 lumen = 10 lux A lux is only 1 / 10 th of a lumen
- Q. What is the average lumen per watt ratio of an HPS and MH?
A. HPS – 140,000 lumens per watt MH – 100,000 lumens per watt Fluorescent – 83,000 lumens per watt Mercury Vapor – 63,000 lumens per watt Incandescent – 17,500 lumens per watt
- Q. What is the definition of PAR?
A. PAR stands for Photosynthetically Active Radiation
- Q. What is the PAR value?
A. PAR value is the amount of light usable by the plants
- Q. When the lights are off what’s going on with my plants? Obviously they don’t just sleep so what do they do?
A. In the dark cycle the plant shifts its focus from leaf production to root production. The leaves transfer extra stored energy down to the branches and roots. The plants dark cycle is very important. 24 hour light cycles are not the way to go despite radical theories and tests.
- Q. How high should my lights be from the tops of my plants?
A. The lamp should be 18 – 24 inches away from the tops. Use an oscillating fan to circulate air on the tops of your plants. This will help with the removal of heat produced by your lamp and also deliver fresh air across the undersides of your leaves which are where the plant breathes in through tiny microscopic pores called Stomata.
- Q. What is the Kelvin rating on a bulb mean?
A. Kelvin is the unit of measurement expressing color temperature. Each lamp has an aggregate Kelvin temperature that indicates the bulbs spectral output. For indoor gardening a bulb with a Kelvin rating between 3000-6000 will be sufficient
- Q. Can I use a green light in my grow room in the dark cycle? I’ve heard that green light won’t wake up my plants?
A. Yes you can use a green light in your grow room. Plants do not respond to the green range of the spectrum.
- Q. What is a more efficient reflector to use if my lamp is universal, horizontal or vertical?
A. Definitely horizontal. Horizontal reflectors can reflect up to 40 % more light back down to the growing area. The light form a bulb is emitted form the arc tube located in the center of the lamp. If it is burning in the horizontal position, half of this light is being directed at the plants while the other half is being reflected back down form the reflector giving a complete distribution of the light. If the lamp is burning in the vertical position all of the light goes out the sides and had to be reflected back down minimalizing the intensity being directed at the growing area.
- Q. What is a good application for the parabolic reflector?
A. Parabolic reflectors distribute the light very evenly but are extremely inefficient in their use of light. They are excellent for a vegetative crop or for lots of seedlings or cuttings but are not very good for high yielding crops with high intensity demands.
- Q. Parabolic reflectors distribute the light very evenly but are extremely inefficient in their use of light. They are excellent for a vegetative crop or for lots of seedlings or cuttings but are not very good for high yielding crops with high intensity demands.
A. Choose the flat white over semi gloss. It reflects better than the semi gloss. Glossy paint has light absorbing varnish that does not reflect as well as the flat white does.
- Q. What is a light mover? Are they beneficial to a grow room?
A. A light mover is a mechanized device used to slowly move the grow lamps around to achieve maximum efficiency from your lamps. They come in the form of a 6 foot track which moves the lamp back and forth slowly, approximately every 10 minutes each way. Sun circles are designed to rotate the lamps in a slow circular motion above the growing area. These are both very beneficial to an indoor garden because you can bring the lamps closer to the plants without burning and the light can get at all angles of the plant saving the grower from constantly rotating the plants. Light mover are usually very efficient to operate and can really help with an increase in yield without the increase in lamps.
- Q. My ballast seems to operating at a high temperature, but how can I know if it’s too hot?
A. The best way to tell if your ballast is running too hot is to take a wooden kitchen match and touch to the ballast box. If it ignites the match then it is operating too hot. I would recommend having it looked at by a professional or have it serviced at your local hydro shop.
- Q. Does the heat coming off of my ballasts make a big difference in my grow room?
A. Yes if heat is already a problem in your garden then I would suggest moving your ballasts outside the grow room. Especially if there is more than 1. They can really increase the overall room temperature.
- Q. What is the most efficient lamp to operate?
A. The 600 watt HPS is the most efficient High Intensity Discharge lamp to operate to date. It has the highest lumen per watt ratio of any of the HID lamps on the market.
- Q. What is the best position to have my ballasts in?
A. If the ballast is mounted in a protective housing (ballast box) then it should be kept up off the ground. Milk crates or cement blocks are excellent for this. Place a piece of heat resistant rubber under the box to reduce any vibrations the box may give off. They can sometimes really hum and that can get irritating. I suggest having all ballasts mounted in proper casings. Un- protected ballasts are usually trouble waiting to happen.
- Q. Is it better to have bigger taller tomato plants or short and bushy?
A. For an indoor garden the shorter bushy plant would be the way to go. The taller a plant is the more energy it wastes to move waters and sugars back and forth within itself between the roots and the leaves. Tall plants often need to be staked up while the shorter plants are usually much heartier and can support their own weight. If you have a green house and can tie your plants up then the sky is the limit but for indoors go with a shorter stalker plant.
- Q. Is it good to trim the bottom shoots off of the plant and leave the tops?
A. An untrimmed plant can cause itself to waste energy to supply the useless shoots on the bottom often referred to as sucker. Carefully remove the unwanted bottom suckers but leave on as many good green leaves as possible.
- Q. Is it a good idea to strip some of my plants leaves so the flowers get more light?
A. No. Your leaves are what take in the light and use it for photosynthesis not the flowers so leave the leaves on unless they are 50% or more damaged or yellow. The leaves are very important to your plant and removing them only slows down photosynthesis and reduces growth rate.
- Q. Is vitamin B-1 good for the plants?
A. Yes. Vitamin b-1 stabilizes the plants chemistry very well while also acting as a catalyst which helps make all the enzymes in the plant work their chemistry smoothly. Different manufacturers all create their own blend of B-1 containing other vitamins and hormones to give them their own unique vitamin b-1. B-1 is often used to treat plant stress and during transplanting to help with the shock. It is also excellent to use as a foliar spray.
- Q. What is the purpose of the leaves on a plant?
A. The leaves are basically sugar factories for the plant. They act as a solar panel taking in the light combining it with water and C02 to make usable sugars. Then they send these sugars down to the roots when the roots combine these sugars with oxygen it converts it into usable energy for the plant. The more oxygen to the roots, the more energy it can transfer to the plant.
- Q. If my plants got too tall, what can I do to get them down to size?
A. You can cut them back from the top but you have to cut in a manner that you always leave lots of new shoots available to come out. If you cut away all of your shoots you lose all potential new growth.
- Q. I have tomato seedlings under a fluorescent light and was wondering what my light cycle should be?
A. The light cycle should be at 18 hours of light and 12 hours of darkness. This will be best for optimal growth and will help keep the seedlings stocky and short rather than elongated and weak. The plant needs to sleep. This is where it goes from leaf production in the day to root production at night.
- Q. How important is it to have the lights at the right height from the plants?
A. Having your lights too far can decrease your yield significantly. Light intensity virtually doubles every 6 inches closer the light is to the plant
- Q. How important are reflectors?
A. Reflectors increase available light by more than 30%. The proper hood over the lamp and reflective materials on the wall can double the growing area. Growers who use the most efficient reflectors can harvest up to twice as much as those who hang the lamp with no reflector.
- Q. Are parabolic reflectors good for a veg room?
A. When growing plants in the veg stage and growing clones parabolics are perfect. They are somewhat inefficient in their use of light for blooming but for vegetative stage they distribute the light over a much larger space which provides even growth for the plant.
- Q. What is an air-cooled reflector?
A. There are several air cooled reflectors on the market today. Some use a reflective hood with protective glass face and fans to move the heat the bulb produces through the hood and out the ducting system. Most people vent the heat through a carbon filter before discharging the air out of the house.
- Q. What kind of paint should I paint my grow room with? Glossy or Flat?
A. Flat white paint contains little or o light absorbing pigment, therefore flat white paint absorbs virtually no light, it is almost all reflected. Flat white is whiter than gloss white and is a better reflectant. Glossy white is manufactured with more light absorbing varnish. The glossy surface lends itself to bright spots and glare. Flat white contains less Varnish and inhibits the path of reflective light much less. It also has a mat texture actually providing a more reflective surface.
- Q. Are light movers any good? Is it a worth while investment for my garden?
A. The most efficient way to replicate the movement of the sun through the sky is with a light mover. A light mover is a device that moves the lamps back and forth across the ceiling of the grow room. Motorized light movers replicate the suns path through the sky even though it does not constantly move east to west. The linear path distributes light evenly. The slower the light mover moves the lights down the track the better.
- Q. Is it okay to hang my ballasts raw from strapping from the ceiling?
A. No!!!! This is the stupidest thing that indoor gardeners can do. This is a total fire hazard and just all around plain DUMB. Don’t be cheap. Store ballasts properly in ballast boxes. It’s not worth burning your house down to save $20.
- Q. My bulb is really tight to get into the socket. It is really hard to thread in. What can I do to help this?
A. You can put a bit if Vaseline on the bulb end to help it slide in easier. Be careful not to cross thread the bulb.
- Q. I have a Honda 5500 watt generator and I am wondering how many 1000 watt grow lamps I can operate from this particular generator?
A. You could run 4 1000 watt lamps from this generator. Usually for Honda generators you can count on 1300 watts being needed per 1000 watt lamp so 4 X 1300 equals 5200 watts so you can run 4 lights.
- Q. What kind of generator is better? Gas or Diesel?
A. Deisel motors are more economical to run but they are noisy and produce allot of fumes. If you run a generator be sure it is properly vented or you may not wake up.
- Q. What kind of timer do I need to run a 1000 watt HPS lamp?
A. Purchase a heavy duty grounded timer. Intermatic makes the best timers for single lamp operation. Be sure to check the amps they are rated for as some are different from others.