What are HID Grow Lamp Systems?

In our previous post A Guide to Grow Lights we explained why it is necessary to use specialist grow lamps to grow cannabis indoors, and ran through the various types of artificial lighting available. Here we look at the most popular choice in a little more detail and describe the component parts.

HID Grow Lights

HID stands for High Intensity Discharge  and this type of grow light is based on the principle of delivery a large amount of light over a small area. The key point of an HID light system is the large bulb (around 30cm / 1 foot) in length. This bulb is filled with gas and two electrodes arc an electricity current which ignites the gas and emits a powerful light. Bulbs are filled with two types of gas, Metal Halide and High Pressure Sodium, which is explained further down. To supply the electrodes with the right sort of current a ballast is used which converts your regular electricity into the type necessary for the bulb. A third component in the HID Grow Lamp system is the reflector or hood which acts both as a lampholder and a means of directing the light downwards towards the plant canopy.


This is the specialist piece of equipment necessary to run a high density light system. The reflector (hood) with self-contained bulb socket plugs into the ballast, and the ballast is plugged into your power socket. It converts this electricity into a form usable by the bulb to produce large amounts of light. Ballasts come in a range of “sizes”:

  • 250 watt – good for young plants or a one plant grow
  • 400w – small personal grow
  • 600w – in Europe, the most commonly used grow light size
  • 1000w –  in USA 1000w light systems are often used.

Bulbs come in these sizes and may need to match your ballast. Most reflectors are “one size fits all” but some have a small/medium/large version e.g. CoolTubes.

As well as the different sizes, ballasts come in 2 types:

  • Magnetic
  • Digital

Advantages of using a Magnetic Ballast in your grow room:

  • cheaper to buy
  • simpler, with fewer components
  • will work with any bulb as long as it is the corresponding size
  • not fussy about the quality of the power source – they can cope with power spikes and fluctuations
  • easily repairable
  • bulbs last longer
  • longer warranties


  • usually heavier and bulkier due to the electromagnetic core (although improvements are being made by some brands)
  • very cheap versions can have quality issues – and for this translates as a safety issue. A faulty ballast is a fire hazard.
  • not energy efficient and produce more heat as a side-product
  • use a small starter circuit which means that as the ballast starts up the bulbs flicker.
  • hum
digital ballasts for the grow room

Why a Digital Ballast is worth the extra money:

  • Higher output than the same size magnetic ballast (up to 30% more): which means for the same amount of electricity drawn, your plants will get up to a third more of that light they need to convert into growth/flower production.
  • Produce less heat and the power given to the bulbs is more stable so they burn with less flickering
  • Less noise
  • Adjustable wattage: this is very useful. When plants are young or in veg stage, they need less light than in full flower. Turning down the power on the ballast means you save on unnecessary electricity usage.

Disadvantages to using a digital ballast

  • Super sensitivity. If your electricity supply is variable and “spikes” the ballasts will switch off – and sometimes burn out bulbs in the process. Even if you don’t lose the bulb, coming in to find your room has been in complete darkness when it should have been lit is a bad thing.
  • Some ballasts have inadequately shielded reflector cables causing RFI (radio frequency interference), possibly effecting nearby TVs and radios
  • Cost
  • Less dependable in the long term

To sum up:

Generally it pays off to buy a branded digital ballast. Not only do they provide a better light, but more of it. The possibility of delivering less power at stages in the plant’s life cycle will help to offset the extra cost. However, if you’re just starting off on a budget, or if you have uncertain electricity supply, then the digi ballasts extra sensitivity will prove problematic. One thing is certain: beware very cheap unbranded Chinese makes as part of bargain basement lighting kits: the biggest cause of grow room fires is a faulty ballast.

Reflectors or Hoods

Reflectors do just as their name implies: they reflect the light down from the bulb towards the plants. They also contain the lampholder into which the bulb is screwed, and the cable connecting the lampholder to the ballast.

There are many types and makes of reflectors on the market but here are some of the most common:

1. Stucco Reflector

The most basic reflector is simply a thin metal sheet made from Stucco and containing the lampholder. These are usually very cheap – around 15€ – but the savings you make on purchase cost may well lose you a significant amount of yield: these reflect the light over the minimum area possible, do not reduce heat, and have only 80-85% reflectivity.

2. Air Cooled Reflectors

cooltube reflector

These fall into two types: the Cooltube and the Air cooled Hood. If heat build up is a big problem within your grow room example in a small confined space, or when sing multiple lights) then using these makes a big difference. Ducting is attached to the reflector and the extractor pushes air through, pushing out the heat produced by the bulb. Depending on the number of lights you’re using you may need to use a separate extraction unit for this. If you are running a sealed room environment using CO2 where you don’t extract the air, using a cooltube system still enables you to pull out the heat. The more basic cooltubes have very small reflectors so obviously do not reflect as much light downwards, whereas the air cooled hoods feature a normal sized reflector. Because the light is cooler than using an open-ended reflector, the lights can be hung much closer to the plant canopy.


  • lose some light energy through dissipation through the glass
  • can create hotspots and potential light burn

3. Open-ended Reflectors

Similar to the basic Stucco model but with refinements in design and build materials. Probably the best of these type is the Adjust-A-Wings range which claims to increase yield by up to 50% and coverage areas up to 75%. (read more about the Adjust-A-Wings here).

Tend to create the best spread of light with uniform coverage. However, heat stays trapped in the reflector area and therefore they need to be positioned higher up. Great in combination with a lightrail.

To sum up: there’s a huge price difference between the bottom end budget reflector and the highly designed specialist models.


Bulbs for an HID Grow Light system are large – nearly a foot in length. Like the ballasts, they come in a range of sizes:

  • 150w (uncommon)
  • 250w
  • 400w
  • 600w
  • 1000w

and you need to match your bulb size to the ballast you are using.

As was said at the beginning, these bulbs work because the electrical current ignites the gas within them.  Metal Halide bulbs (MH) use Halogen and produce a light at the blue end of the spectrum, High Pressure Sodium (HPS) uses the same principle with a sodium gas, producing a reddish orange light. In theory, you will need a Metal Halide bulb (which appears bright white, and covers the blue end of the spectrum) for marijuana plant growth, and a HPS (High Pressure Sodium) bulb for flowering. HPS bulbs have twice the lifespan of a MH bulb (around 18,000 hours as opposed to 10,000 hours), but their red-orange focus means that they can produce spindly, stretched vegetative growth. They are however ideal for flowering.

The best scenario when using HID grow lights is to run with a Metal Halide bulb for vegetative growth, then switch to HPS for flowering. Alternatively, you can operate both lights at the same time – but this will shorten the lifespan of the system and increase electricity consumption and heat whilst at the same time not giving a comparative increase in bud production.

But, unless you intend to grow your plants in vegetative stage for a long period, it is perfectly feasible to produce a beautiful crop using a Dual Spectrum bulb. This is an HPS grow light system with a small percentage of blue light included to prevent over stretching and closer node space. Commercial cannabis growers have for a long time added one MH system to every 9 HPS systems to get the same effect. Alternatively you can grow your seedlings or cuttings on under a CFL then put straight away into flower at around age 2 weeks under a standard HPS. This method of growing is ideal for hydroponic growing, and is commonly called a “sea of green”.

Like everything else, quality costs. A budget buy bulb may cost a quarter of the top end model, but produce less light even though its rated for the same amount of watts. Bulbs should be changed every 3 seasons or so as although they still function to the human eye the amount of light diminishes.

How many plants can I grow under my HID lighting system? Or, what lights do I need to cover my grow room?

This question is a bit like asking the length of a piece of string .. and yet its asked all the time. The answer is: “it depends on the size of the plant” .. probably the best answer is to consider the coverage area of each size light and grow accordingly. Information on the internet can get very confusing as writers talk of lumens etc. but as a rough guide, consider that the very best bud production happens at 60 watts per square foot. I’ve commonly seen area coverage guides suggesting that (for example) a 250 watt light will cover an area of 3′ by 3′. This would give a watt/foot ratio of 42: I think you would be better off reducing the area to 2.5′ by 2.5′ at most, with 50 watts/ square foot. I say this from personal experience : the nastiest, stickiest bud I ever grew was with a ratio of 62 watts/ square foot. The plant had big juicy buds which went further down the plant than when I grew the same cuttings with the same conditions at 40 watts/square foot. You’ll probably end up with less grams/watt using this ratio, and your electricity bill will be slightly higher, but believe me, if you are growing marijuana indoors for quality rather than quantity, this is the route you should take.

Unless you have unlimited height available, you probably want your plants to end up at around 3 feet tall. At this size, in pots big enough to give good root-ball space, you can grow 2 plants under a 250 watt HID grow light and get good bud from it. Alternatively you could grow 5 smaller auto-flowering plants that end up around 2 ½ feet tall.

Advantages of HID for indoor marijuana lighting

  • Relatively cheap to buy: you can get a usable 600 watt HID grow light for $100 on ebay.
  • Tried and tested. Lets face it, the fact is that the majority of cannabis growers won’t consider using anything else. We know that they work and work well.
  • Because they’ve been around for the past 15 years (or so) as the major source of lighting for marijuana, nutrients, additives etc. have all been refined to suit growth under these lights. Plants grown under different systems are showing mineral deficiencies with standard foods that don’t occur under HIDs.
  • This will change .. but at the moment unless it states otherwise, any information that you read about indoor gardening will assume you are using HID

Disadvantages of HID lighting for marijuana production:

  • The initial outlay may be low, but the shelf life of a HID is short: at 12 hours daily, expected bulb life is said to be 3 years. Most growers would however replace bulbs after 1 ½ years. Ballasts etc. also deteriorate in efficiency so rather than just replace bulbs, long term growers replace the whole system at this time.
  • Electrical consumption. We all know that a major factor in cannabis grows being discovered is as a result of suspicious increases in power consumption. Remember that as well as running your lights, you will also be powering extractors, fans etc.
  • Heat. This is another reason why growers get busted: tell-tale heat signatures coming through their attic roofs like a beacon to the bobby.
  • Heat also has major implications on the way you grow your weed. Healthy temperatures for an indoor grow are between 21ºc and 29ºc. Even in winter you will find that you will have to work in a way of reducing the heat in your grow room down to this level. Of course, for ventilation reasons, you should have an extractor anyway: with HIDs, this needs to be a reasonably large one (see ventilation for CFM ratings).Dealing with, and monitoring your heat levels becomes a part of your growing technique. And if you live anywhere where outside temperatures rise during the summer, you can forget about indoor growing.


We all know that the right lighting is necessary for clones and seedlings. Too strong a light, and they will suffer. Too little light and they will stretch and flop.

Over the next few weeks I will be conducting a series of amateur trials looking for the

most efficient amount of propagation lighting needed to cover a large propagator/dome for the first ten days of  life

ensuring that

  1. for the case of clones that they root well and have no apparent stretching
  2. for seeds that again they grow well with no apparent stretching

Now regular readers of this site know that I’m very much into my LEDs, so why change anything?

I will be starting with a 10 watt integrated led with a 120º angle


and finally 28 Dinafem Original Amnesia cuttings/clones  in 25mm/1″ Grodan rockwall cubes

All of the above pics are the clones at 4 days after cut , so far looking healthy but no signs of roots as yet.

The next test will be using a 20 watt Led to cover the same area and we will see how much a difference (if any) in health and speed of rooting.Also this week we will be doing the same trial with seedlings with first the ten watt followed with the 20 watt

All leds used in this trial will have a 6500K spectrum

So whats the point in all this ?

What I’m trying to find out is the correct amount of light for both seedling and clone stage

These are cheap floodlights. Will they be adequate for young and tender plants?

It needs pointing out that they have no cooling system, but whilst they won’t be in constant use (I’m not doing cuttings commercially) I am expecting them to last 2 years with regular use.

The point is that if these work, then for surprisingly little money – $25 plus postage, I will be able to start seedlings or clones off in a small space whilst my main plants are finishing – and with only an additional 10 watts of electricity.

Heres the link where I picked up the two very reasonably priced LEDs. If anyone else wants to help with the trials without breaking the bank:

10 watt integrated LED 120º 6500K

20 watt integrated led 120º 6500K

or you can buy from amazon.com via our online hydro store: [columns divider]

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More and more cannabis growers are moving to using LEDs and that includes many of the team here at the Growers Guide to Cannabis. Why? Well for us, LED grow lights just make growing cannabis easier.

Are LEDs cannabis growing’s problem solver?

LEDs solve many  issues for cannabis grows:


One of the biggest issues many growers face is dealing with heat extraction. Because LEDs increase environmental ambient temperature by only a º or 2, there’s less stress on the plants, and less expense dealing with heat.  Its my belief that without the stress caused to plants by excess heat, LEDs make growing easier for a lot of beginner growers. Its just one less issue to have to deal with

What are optimum growing temperatures for cannabis? See here

Electricity Useage

Watt for watt we find that LEDs produce 25-40% more yield than HPS. Turn that equation around and you get: “to produce the same yield as “x” you use a LED drawing 25-40% less power”. Add the fact that your extractor is smaller, you’re not running air-con etc etc and your electricity bill falls significantly.

Read our LED vs HPS grow off where we discovered for the first time that LEDs produce more bud than HPS. It was our “on the road to damascus” moment, and we’ve had the same results time after time since.

You’re less likely to get busted

Why? Well LEDs won’t stop you or your mates blabbing about your “secret” room in a pub full of policemen, but because they have no heat signature for thermal imaging cameras to pick up and because an LED grow room uses less electricity than an HPS grow room, its not so obvious that “unusual activity” is happening at your premises.

Use a carbon filter, keep your mouth shut and quite frankly with an LED grow, no one needs to know!

How do LEDs work to grow cannabis?

I suggest you start by reading this article here: LED grow lights and cannabis

Do LEDs work to grow cannabis?

well the proof is in the pudding ..

T5 grow lights: will they grow cannabis?

Regular readers of this site will know that after many years of using HID grow lights (and wrestling with the issues of heat production, stretching etc) that I’ve found my solution in the best LED grow lightsBut LEDs aren’t the only alternative to HPS and if I hadn’t been convinced by them already, I would now be looking at a T5 lighting system.

Of all the T5 grow lighting systems that I’ve seen used in various grows it is the Quantum “Bad Boy” Range which really stands out. I’ve seen some superb cannabis grows done using this light (check out Jackal’s reports on autoflower.net for example).

So what is the Quantum Bad Boy and how does it work?

The Quantum Badboy succeeds where others fail for a full seedling to harvest grow because it combines a decent coverage area with sufficient output and high performance.

It uses the “Fulham Race Horse Ballast” which is finely tuned to produce maximum output from the tri-phosphor bulbs – 28% more light than T5s using traditional ballasts and yet with no increase in power consumption.

The tri-phosphor bulbs produce a natural colour and light promoting:

  • tighter internodal spacing 
  • thicker stem walls (enabling increased photosynthesis rates)
  • heartier foliage


  • High Output optimized fixture for MAX bang for your buck!
  • Unique folding structure for easy transportation
  • Vented Ballasts and reflectors keep heat to a minimum
  • Bulbs are spaced to provide a uniform light
  • Glass coated aluminum reflectors provide deeper penetration.
  • Multi-volt operation, 120v/240v right out of the box!
  • Bulb Type Lumens Output:
    • T5 Lamps High Output Lamp: 93.5 lumen per watt
    • 2900 K Lamp High Output Lamp: 88 Lumen per watt
    • 6500 K Lamp Super High output hyper-driven lamps and fixtures define optimum production from start to finish.

Quantum makes two types of bulbs, 6500K and 2900K. The 6500, obviously is for veg, the 2900K for flowering. Whats nice is they package and sell them in 8 bulb packs, or you can buy em each separately .

To sum up:

A T5 system CAN grow a cannabis crop from seedling to harvest with low power consumption and minimal heat.  Reading through grow reports on various forums the story seems very similar to when you read through LED journals .. the sceptics at first believing the whole idea is a joke, the actual grower loving the results.

t5 cannabis grow

The quantum Bad Boy is the best addition to my grow room its the best investment I have made my plants are so green and bushy i used a 600 watt MH and HPS before to veg my plants and that was a mistake i didnt know what i was missing until i got the bad boy….my advice is invest in the Quantum Bad boy if you want your plants to be all they can be!!

Do I want one?  Yes!  Would I buy one?

Well at prices starting at $147 for the smallest fixture and $69.95 for 4 bulbs, yes I would. And reading the reviews and having seen the grows, I am actually convinced enough to buy this double fixture:

Make sure you buy the bulbs for vegetative stage and for flower and I think you’ll be looking at a winner. The Quantum Bad Boy is THE perfect solution to any of the following growers problems:

  • excess heat
  • power consumption
  • height restrictions

Buy now .. secure checkout through amazon

led grow cannabis

LED grow lights: will they grow cannabis?

and more importantly, will they flower them?

LED grow lights have exploded in the last few years with more advanced versions seeming to appear monthly. But among marijuana growers there is heated debate on the subject, with traditionalists yet to be converted to the new technology. For newbies the problem is often wading through the techno talk to get to the truth. Lets get back to basics.

LED lights: a brief history

As early as the beginning of the 20th century a British scientist, experimented with a solid state light emitting diode (LED), but it wasn’t until the late fifties before his research was taken seriously. In 1962 the first practical visible spectrum LED was developed by American Holynak, “the father of the light-emitting diode”. Initially used in a variety of settings, from TVs to watches, it has only been in the past 10 years that problems with reliability, stability, strength and spectrum have been resolved. Where once LEDs were used mainly for red indicators in electronics, they have now moved into all wavelengths, including visible, ultraviolet and infrared.
Research by scientists such as those at NASA and corporate development aimed at horticultural businesses worldwide have refined the specifications to the point where LED lighting is not only a viable form of alternative grow lights: it is possibly the future of grow lighting technology.

So how do LED grow light systems work?

An LED grow lamp looks very different from an HID grow light. Whereas the latter looks like an oversized industrial light bulb capable of kicking out a lot of brightness and power (which it does), the LED systems are self-contained boxes full of tiny bulbs. Each grow bulb is small in area (less than 1mm2) and uses integrated optical components to shape its radiation pattern and reflection. To understand why LEDs are being promoted as a superior option for growing cannabis than HID grow lights, its necessary to understand the principals of wavelengths for chlorophyll absorption.



In its simplest form, the plant uses blue light for growing, and red light for flowering. The process whereby plants grow is photosynthesis, whereby CO2 is converted into organic material using energy derived from sunlight. This energy is absorbed through special proteins containing chlorophyll, BUT chlorophyll only absorbs light from particular parts of the spectrum. For example, it uses hardly any “green” light but instead reflects it, hence the reason plants are green. And its here that the first LEDs to be experimented with for growing cannabis got a bad name. They just used a single band of blue and a single band of red. This is fine for simple crops but failed when launched onto the market for more complex plants – such as cannabis

Today’s more sophisticated LED grow lighting systems produce light at the correct wavelengths of growing and flowering cannabis by combining four separate LEDs into clusters, each bulb emitting light at one of the four chlorophyll absorption peaks.

For cannabis growing, you want to see lights aimed at 439nm, 469nm, 642nm and 667nm. Because each individual light is specific to a certain point in the spectrum, a system of lights covering say 1m2 will contain percentages of light colours to provide optimum use by the plant at all stages of its growth. The ratio of between 4 – 8:1 red:blue is now often augmented by additional orange components. It’s claimed that up to 90% of LED light is utilised by the plant. In comparison, while HID lights do tend towards one end of the spectrum – i.e., metal halide for blue light, high pressure sodium for red, the light you see is more like an intense standard light bulb: they emit light through all the spectrum. Between 15 and 30% of light produced by an HID is within the wavelengths suitable for cannabis growth. This is why they need to be so powerful, so that that 15 – 30% is strong enough for good growth.

The Advantages of LEDs for growing cannabis

  • LED grow lights emit light at optimum wavelengths A good LED grow light provides almost only the spectra of light that the plant needs, with hardly any wastage. In theory this means bigger, better plants.
  • Heat LED grow lights produce virtually no heat. This means that less investment, energy & thought has to go into dealing with heat extraction. Assuming that your grow room is located within your home environment, you probably keep the ambient temperature at around the ideal growing temps.
  • Low running costs
    • Electricity bills are said to be between 40% and 75% less than an equivalent HID or CFL system (including reduced amounts used for smaller extraction equipment, no air con etc)
    • LED grow lights have no filament system to burn out, and have an expected lifespan of 50,000 hours
    • There are no ballasts, reflectors and so on to be replaced.
    • Because there is no heat, it is not necessary to spend a lot of time, energy and expense dealing with it: only a small extractor system etc
  • Security Of course, we all believe that readers of this article possess medical marijuana growing certificates. But just in case you don’t, this aspect of growing cannabis using LED grow  lights is a compelling one. As more and more marijuana grows are discovered due to either suspicious increases in electricity usage or as a result of heat signatures, any system that creates neither of these has to have a large stealth bonus.  LED growing also produces virtually no noise – there’s no give-away electrical “hum”

Size of grow room

OK, so we’ve all measured up in a new location and had to factor in space for distance from plant at maximum size, size of reflectors, sturdy mountings for ballasts, fans, extractor fans with tubing and so on. With LED growing none of these elements need to be considered. LED grow  lights can be much closer to the plants, and without all that excess equipment needed, it really is possible to grow in a small space, discreetly. See here for more information on constructing your own LED grow box.

 What must be remembered is that the science of growing marijuana indoors is not to replicate the natural environment, but to optimise it to the nth degree. Hydroponics produce great results because they enable the cannabis grower to define exactly the correct amounts of certain nutrients available directly to the plant through water, which is itself kept within a certain pH range. Similarly he/she controls the ambient temperature, introduces carbon dioxide, sets the length of time light is available. With LED lighting, it is possible to exercise even more control over the quality as well as the amount of light available for the plant

AF-600 LED grow light / 25 plant auto grow day 14

Days 7 -14

  • outside temps: 28-38ºC
  • inside room temps: 23-26ºC
  • rh: 35-65%

chemicals used this week –

  • General Hydroponics 3 part. 5ml of AB&C for each 25L bucket
  • 5ml Cal Mag for each 25L bucket
  • 10ml Rhizotonic
  • Lots of pH Down!
  • desired EC reading 1.0, desired pH reading 5.7. Adjusted daily.
  • on day 14 started hydroponic peroxide (H2o2) 17.5%, 10ml per 25 L bucket
  • sexing – have identified 3 males and 1 female on day 14 (males removed).

That’s the boring stuff over. I just wanted to put in bullet points so that any newbie can refer to it (or me come day 62). On day 8 I fired up the bubblers with the above specs, as the roots were pushing out the net pots.

Within 24 hours I noticed excellent root growth and it started getting exciting for the next 7 days as the roots stormed out of the pots into the bubbler. At least 3 times a day, I would lift the lid, raise the pots high and proclaim to my wife “look at this!” … strangely enough she didn’t share my enthusiasm. Women!

However I have been slightly concerned (but then I worry about everything) about pH fluctuation, as it seems that every 24 hours, when I tested with the Tri-metre that the pH had raised from 5.7 to 6.8 or sometimes 7. I seem to be pouring a lot of pH down into the system to keep the pH stable. This cant be great? If anyone has any thoughts on this I would be very grateful for them.

Physically though, looking at the seedlings they seem to be doing great, with only tiny amounts of stress showing on the leaves, no apparent stretching and good colour (no signs of bleaching). I started the seedlings off at 42″ from the canopy. I haven’t lifted the light so they are now about 40″ from the AF-600. On day 12 I changed the grow light setting and increased the number of blue panels (switch 1 on, switches 2,3 & 4 off). The light is now running at 40% of its power – WOW I am really starting to dig this light and if for nothing else the pure versatility of it.

Not a lot else to say really. Above and below are a couple of pics at day 14. What I would say is that in comparison with the seedlings in coco-perlite, they are doing fabul-ose-ly! Whether this is more the result of the AF-600 grow light or the hydroponic bubblers, its impossible to be sure. What I do know is that this combination of blue spectrum light with hydro is perfect. These little babies are getting absolutely the best start possible. And I say that with 15 years growing experience, indoors, outdoors, hydro, coco-perlite, soil, 4 crops with this same batch of seeds … this is going to be beautiful.

On days 13 and 14 I was able to identify 3 males and 1 female. Now I’ve been working on this particular strain for 2 years and I’ve never seen sign of sex this early. Another indication of things to come?

On day 14 I started adding H202. Didn’t think they were lacking, but I had just been to the grow shop and got some. Sometimes ,I should remember that less is more … but god how I wish I had a CO2 system right now. More can be more!

I’m hoping by the time the next report is written that all the females will be selected and the NFTs will be running. The missus will be glad to get them out of the bedroom too ..

I am going to take a gamble now. Because of the size of the seedlings and their excellent booming growth rate and my increasing confidence in this light system, I may only put 12 seedlings on the table under the AF-600. I think that despite them being a shortish auto, they are going to be big enough to fill it. I’ll play it by ear .. no promises! Also, if I do this, I will go against all advice from other auto growers and nip them out. I actually think that in optimum growth conditions, autos CAN be pruned and will produce more per plant with a touch of early meristem tip pruning.

Thats it for now, we are about to enter the most crucial stage in auto growing! Wish me luck ..

Happy tokin.


AF600 LED grow light – a 25 plant autoflowering test grow

600 watt draw LED grow lights …

For any serious grower, these are the ones we need to see proof of: can LED grow lights produce at a level of a big HPS?

So, welcome to my test grow of the AF600. This one has me excited! (I’ve done a few trials for Fero in the past and each time they bring out a new light things just get better, so I’m expecting great things from this one.)

I’m going to be doing this grow looking at how well this LED lighting system works from a number of different angles:

Grams Per Watt

Firstly of course we will be testing for gpw (grams per watt). Bear in mind that this grow will using a auto strain and as experience tells us that “as a rule” autos will produce slightly less per square meter than traditional photoperiod varieties, allow a little tolerance for this .. I’m an “auto fiend” and as this is one of my own varieties that I’ve been working on for the last couple of years I’m going to go ahead and do it anyway …..my mother always said I was a stubborn little bugger!

Oh .. and to be pedantic, the AF600 has a 570 watt actual draw so that’s the ratio I’ll be working with come crop time.

Optimum light and power consumption

Also I will be looking at the efficiency of this light: the wow factor that takes this from a powerful unit onto something really special is the settings options: four switches that mean that at each stage of growth I can change

  • the amount of leds that are available    &
  • the light spectrum which I choose to use

The combination of these two effects is that I should be able to grow a cannabis plant from seed to harvest using just one, large sized (600 watt draw) lighting unit. And not only that, but as the plant moves from seedling to strong vegetative growth, from flower set to buds blooming, I can control how much power is offered to the plant (25%, 50%, 75%, 100%) and also what end of the spectrum the plant receives most of its light from.

Heat and Interior Growing

As a by product of this test (and others) I’ll be looking into the question of heat control in  the indoor grow room. I know some of you UK growers are just glad to see a bit summer sunshine no matter what, but lets face it, pretty much the world over heat management is a big factor in any indoor grow using HPS lighting.

This grow is situated in a semi arid area where summer temps touch (and exceed) 40 degrees. Now one of the biggest pluses of growing with LEDS is the lack of heat they produce. I know cannabis growers who are struggling as we speak with HID systems even though they are using 2.5K airconditioning systems with half the amount of light that I am using.  Thanks to this trial, the “safe-guard seedlings” in coco-perlite, and a seed run I’m doing, I am running over 2.5k actual draw of LED lighting in a 7 square meter area. I’m using a 125mm rvk extractor and a 900 watt portable air con unit. Lets see how the system copes with the summer heat as we move into August!

So rather than prattle away for a couple of thousand of words …  I’m going to bang straight into this trial and let anyone who reads this report make their own minds up explaining the different features as and when I use them.

Get ready for lots of “pink” pics and eventually lots and lots of “bud porn”!

Days 1-7

  • average outside temps 25-35ºC
  • average temps inside room 23-25ºC
  • average RH 45-65 %

OK I popped 100 seeds, germinated on tissue paper, and then put into rockwool. Lost a few to the kitten (why?) and am left with 94 seedlings. Now I’m going to be putting the AF600 over a hydro table, but as my seeds have not been feminised, I can’t put them straight into the trays. Not quite able to cough up the 200 quid for a X-stream aeroponic propagator right at the moment, I’ve decided to have a go at building my own “bubblers”(dwc). As usual with this kind of do-it-yourself job, it all depends on sourcing the right materials. I’ve had problems with a d-i-y- bubbler in the past so I have 45 seedlings in bubblers to go on to the hydro-tray (ideally I need 25 females from these to fill it nicely). The other seedlings I’ve put straight into coco-perlite under an adjustable LED as a fall back. All going well these will provide some comparison to the strength of the AF600, and you’ll see a post on “how to make your own bubbler”. All going badly, I’ll still have some seedlings left to grow on under the AF600. I realise the second group aren’t a strict control group, but it should still provide some level of comparison (for myself at least).

Until I see the roots pushing out of the net pots I will be watering from above a few mils of 5.8 ph’d water twice a day until we fill the pots and fire up the bubblers.

looking at them by eye, on each of the two panels I can see 8 blues, 6 assorted reds and 1 infa red. I will be contacting Fero and Area 51 for some layman’s specs for each one of the different power and spectra settings and will update this when I receive them.

and finally “fall back plan” in total 42 unsexed seedlings sat in 13 cm pots under the adjustable led on 1 third power however with the adjustable you only have 3 settings which switch on and off  (3 ufos) so for the seedling stage they will be running at 113wats (plus fans).

BUT each ufo has identical spectra so you are not able to target the correct colour specrum for each stage of growth as you can with this clever AF600 badboy

See you next week with the Day 7 to 14 grow report of the the AF600 trial led grow!

Happy tokin

Unfortunately when we migrated the Growers Guide to its new format, we lost most of Maxwell’s photos, which is a real shame 🙁 . Sorry Max!

Applying what I learned from my first grow with my Fero LED’s!

7/14/2012:  I just finished the last of the bud from my first ever grow … how sweet it was!  I hoped it would last until my next harvest, but I was quite generous to friends and to myself of course.   I am 4 weeks into my second grow with my Fero 360 lights, and the first time I have used them  from the start of veg and the plants are looking great!.   My first grow can be viewed HERE btw.   I was initially leary about LED`s  and I am not a expert on grow lighting, but I have done a ton of research, and luckily have very smart friends who are in related industries.  I am convinced that LED lights are the next generation of grow lights.  Yes, my humble opinion, but I am basing it on energy savings, lower heat and similar results to HID lights (most comparisons have shown to been similar or better).  Conversely, I have a close friend who is also replicating my current grow (and my last one ), same strains, using florescent  and so far my yield was double his, and my plants resembled bushes compared to his stretched looking sparse plants.  I don`t really want to compare LED and HID lights though because I have never used HID before.  I can only report that the LED at least produces twice the amount compared to florescents and are ideal in situations where heat is an issue, use much less energy, and are the perfect closet solution.  On a large scale, I`m not sure, but I`ll put my money on these LED`s.

Last time, I reported every week until I harvested and included alot of pics showing the weekly progression of my adventure.  That was a lot of work!  This time I will do periodic reports instead, but I want to try high-light the things I learned the first time.  My first grow led me through quite a new experience and with the guidance of the kind people here on GG2C and post commenters, I learned SO much and picked up a couple methods to increase yield per plant.  Last time I had 5 plants, but lost one to it’s masculinity!  This time I am only growing 2 plants, but I want to see if I can match or beat the amount of bud I got from the previous four.  How do I plan to do this you might ask?  Two lines of reasoning.  1.)  I will have double light per plant, and 2.)  during my first grow, I learned about (and tried) topping the plant and super-cropping the branches.  The topping worked out great … my super-cropping attempt was pretty weak but I feel much more prepared for it this time.  I plan to top and super-crop the hell out these two girls!

This time I chose to try two different strains.  White Widow and Romulan.  I chose White Widow because it is renowned to being one of the finest overall strains out there.  The Romulan was strongly recommended due to it`s skunky taste and high potency … and that works just fine with me!  Just to throw myself a curve ball, I chose coco as my medium instead of soil.  I thought I was pretty smart because I did a ton of research, but I now realize that although coco is perhaps a superior medium over soil on some levels, it`s downside is that it seems to be much higher maintenance.  I made 2 mistakes right from the start.  I`ll tell you what I did and what I would do next time.

WHAT I DID:  I changed from 2 gal pots to 5 gal – good move.  I filled my pots with coco, and a couple days before I planted my sprouts, I pre-soaked the coco with straight water to let it settle and be ready for the sprouts.  I planted the sprouts directly into the big pots a couple days later… why mess around with transplanting several times.

WHAT I WOULD DO NEXT TIME:  I would first mix the coco 50/50 with perlite … post-research seems everyone mixes their coco with this … Doh!  Instead of pre-soaking the mixture with water, I would pre-soak it with water mixed with weak mixture of nutrients (including cal/mag).  As I understand, coco is a completely nutrient free medium (unlike soil).  I`d still plant the sprouts right into the big pots.

Last time I nearly drowned my little sprouts because I was so anxious to feed them … this time I did the opposite and under-watered resulting in very slow growth for the first 2 weeks (see pics below) … this puzzled me.   I finally turned on the water and BOOM …they exploded!

My White Widow and Romulan after 2 weeks.  They look so sad like my first grow in the early stages!  I am hoping my third shot at dealing with sprouts will be the charm!

After 4 weeks and some better watering habits.  I started giving them a half liter 2 weeks ago and now they each get one liter.  I alternate my waterings with water with cal/mag and nutrients with cal/mag and occasionally just use straight water.  The White Widow definately is a thicker bush with a more aggressive undergrowth.  Both plants have been topped once.  You can see that the Romulan has strange looking red stems … like rhubarb!  The light is about 40 cms from the tallest plant, the White Widow.

7/24/2012: Due to excessive heat and humidity (75+%!!!), I have had to place an air conditioning unit (which also dehumidifies) in my room. Lucky I am somewhat setup for that as my hot water heater is in the same room and has an overflow drain, so my spare portable A/C came in handy. My White Widow’s upper leaves are curling up like a bowl and are actually sweating drops beneath … never seen this before! I think the unit I installed will correct this … and a change in weather.

Anyways, a few days ago I decided it was time to top my plants more aggressively. My White Widow had some lower colas that were pushing up higher than the previously topped tops … my Romulan on the other hand, is showing much slower growth, especially in the lower colas. I have been doing a lot of fan leaf bending and tucking to expose the lower colas to the light and it seems to be working, but it’s nodes and branches seem like a mini version of her sister. I took six tops from my White Widow including re-topping the two initially topped tops, and I also re-topped my Romulan’s two initially topped tops, but left the lower colas alone to develop more. Since the topping the White Widow in particular has become very thirsty!

I am now giving her 2 liters every 2-3 days … that is double what I was giving her a couple weeks ago! The Romulan is now getting about 1.5 liters every couple days.

Here are the girls today … White Widow and Romulan. The lights are now about 30 cm from the White Widow and they are seeming to love it.

So what to do with my tops … ? My last grow I struggled in understanding how to choose a clone. Now I understand that if it has a growing TOP it is a potential clone. So I went down to my local plant nursery and bought some rooting powder and a tray of peat pellets and …

OMG! What if they all grow .. I can’t handle another 8 plants! LOL I do have some eager friends who are happy to adopt a few … I may find an outdoor spot to plant a couple too, but will certainly keep a couple to veg until my current two go into flowering.

7/31/2012: Well, they all grew … and fast! Within 7 days, the 6 White Widow’s had serious roots shooting from the peat pellets, in a couple cases over an inch long. The Romulan’s were much more conservative but I wasn’t surprised as the plant they came from is abit of a runt. In any case, I now have 8 extra transplanted clones and can now add cloning to my list of successful experiences . I didn’t expect this to happen … it was an experiment … but I cannot handle this many plants, so I have reached out to find adoptive parents. So far I have found a home for 2 and maybe 3 more in a week or so. I will end up with 3 at least, and I’m not compaining at all. However, I now have to find a second area in my place to keep my 3 clones under 18 hours of light (flourescents) after I place my 2 current plants under 12 hours of light in the next few weeks. Not ideal, but I’ll have to use a closet in my bedroom I guess. The great thing is that when I am harvesting my current plants, my clones should be ready for flowering. A good cycle I might want to continue. Here are the 6 that still remain in one gallon pots.

I also decided to do some super cropping this weekend. I tried to squeeze/bend the taller tops 2 nodes down above the thrid to expose the 2 new potential sprouting tops. Here they are (White Widow, Romulan) after the supercrop. The Romulan shows it much better.

8/09/2012: These plants are resilient little buggers! Within a day or so, the tops had bent at a 45 degree angle back to the light. I spent time daily to re-bend them and tuck fan leaves to keeps the lower potential tops exposed to the light. Although the Romulan is a few inches shorter, both have become intense round little bushes. They are such different plants! Here they are abit more than a week later.

So many tops especially on the White Widow! Both are round little bushes! So far so good!

8/18/2012: I started the 12/12 flowering stage today! I am a bit excited and hesitant at the same time. I really wanted to veg these babies into more mature plants to get a mega yield, but I am forced into doing it. The reason is :

I had 8 clones to start with and quickly gave 2 away to a friend. Another friend wants the other 3 but can only take them later so I’ll be raising them for now with some small 2 foot flourescents in my bedroom closet! I know the flowering of my 2 big plants will be at least 8 weeks and I fear if i don’t start now, the clones will be monsters in 2 months. My buddy has been growing 2 white widows with his 6 flourescents and the are about 40 inches tall … they really stretch with the lesser lighting. In any case, I am very happy I will have a new set of plants entering flowering as I am harvesting my current ones!

Here are my current bushes. The romulan (right) is certainly a stouter plant. The white widow is 20 inches tall by 20 inches wide … the romulan is 16 x 16. Two perfectly round little bushes. The white widow has more tops than I can count but many are small little tops still developing so I don’t really know what to expect from bud on them. Little romulan has fewer tops and a much thicker canopy leaving little light to get below. I don’t know what I will end up with, but it has started so

I will soon find out!

My LED light is currently about 25 cm from my white widow and there seems to be no ill effects. I have used cal/mag in every watering and have alternated food with straight water. I am using an organic food that is used for both veg and flowering at different concentrations. My last grow I did 2 plants with organic food and 2 with synthetic and I found the buds from the organic plants were much more tastier.

9/15/2012: Well it has been 4 weeks of 12/12 and all looks great! My White Widow is having some brown leaf-tip issues and some of the edges too, but the buds are looking great so far. I am not sure if it is a defiency of something or too much food. I have tried using straight water doing a semi-flush the last two waterings, so we will see if that helps. Don’t think it is a huge issue though. The Romulan looks lush and green but as it has been from the start, the development of the buds is slower. I don’t think I’ll grow multiple strains together again. Anyway here they are … sorry I have a crappy camera.