Fero LED grow light: Review & Test Grow

Fero LED grow light: Review & Test Grow

This is the second trial we’ve undertaken of Fero LED lights, the first being a hid V led showdown (see here). This time the growers guide to cannabis have decided to do a stand alone grow using the biggest light in Fero’s 4g range,  LED grow light with a 650 watt draw.

Here’s a picture of the system:

Firstly I have to say this is a seriously sexy light. If you had to buy a light on looks alone, this would be the one. Its a sleek monster, nearly 1m 20cm long giving out a dazzling array of lumens. But of course the question is, how well does it function? Readers of the blog may know that I was well impressed with the smaller sister light, the 360 4G. (Apollo 8)

Under this light we decided to use 20 cream caramel autos from sweet seeds. You might remember we trialled this auto in the last trial grow and under the led we pulled 66 grams from one under the 360 4g led in 105 days. This time I’m looking at ascertaining a gram per watt figure, so I’m packing them in tighter than before.

Due to the shape of the light, the grow area is 1.8m by 1m. Its serviced by a 125mm extractor and a 150mm oscillating fan. Until I try out these LEDs with a hydroponic system, I’m definitely convinced that growing in a coco – perlite mix (50:50) in 10 litre pots, and using a feed/water to waste watering system is the way forward.

Its semi-hydroponic, and whilst labour intensive, it makes it easy to respond to your plants’ needs quickly. The nutrients I used were growth technology 2-part for both grow and flowering stage. From day 28 I added one teaspoon of epsom salts for 10L of feed every third water. Weekly towards the end of the flowering period I also added hesi PK 13-14 boost.

Cream caramel auto seedlings day 1 – 28 (Fero 4G 900 Led grow light)

20 cream caramel seeds were placed in a sterilised jam lid on a couple of coffee filters soaked in ph water to 5.6, wrapped in cling film and placed in a dark drawer for 48 hours in the same room as my system so temps at the time of germination were around 21 ºC. After 48 hours all seeds had germinated and we will call this day 1. On day 1 we placed the seedlings in 7 cm pots watered with plain phd water and placed under the led lights. The lights were 100 cm from the top of the pots now normally we would use cfls or t5s strips for the seedling stage but felt for this trial so their would be no other influences we decided to do this whole grow from start to finish using the Fero 4G 900 light. To do this you need to be on the ball as with a unit this powerful its all too easy to either burn or stretch seedlings and would recommend that they are started under one of the above to be honest its a lot easier with less stress 🙂

I know we’ve all seen seedlings a million times on the net, but one of the things that is great is when you look back and compare that first seedlings with the plant when finished: its always quite amazing.

It seems no matter how often I tell newbies on the forums, or friends that are just beginning to grow, that people kill their new seedlings with too much love. Until day 21 I use only plain pH 5.6 water (NO food) and water carefully. Until the root system is established I start by just dribbling a little water in the centre of the pot and increase the amount of water as the plant’s roots develop and spread.

By day 21 the plants are nearly ready to be transplanted to 13cm pots and are given their first feed of 5ml to 10L of water A & B grow. Again, with this first feed I only give enough liquid to make the pot damp and yet not saturated. Three days later I flush the pot thoroughly until there is a minimum of 25% to waste. A week later the roots were established in the 13cm pots and nearly ready to be transferred to the 10L pots.

One of the things that I love about these LEDs is the great early vegetative growth. Because the young plants don’t have to stretch up to get the right amounts of blue light necessary, the node spacing is lovely and compact.

day 28 to 58
OK, wicked they’ve got off to a good start and for this period the growth kicks in over the next 30 days. They are kept on veg feed and every other feed the strength is increased until they are sitting sweet on 20 ml of a and b with the epsom salts added every third water. Growth is good and strong with nice node spacing and good vertical growth. By day 58 most have started slowing down and beginning to think of flowering.
Its easy too see 3 different genotypes within the cream caramel and it looks like I will have to crop individual plants as they mature. Height varies from 40cm to 70cm which makes growing them under one light difficult to optimise light height. So at day 40 I decided to “knuckle” them in order to maintain an even canopy:

well what we after is flower and FINALLY they seemed ready to start entering their true flowering stage. Now according to the breeders sweet seeds they should be ready by day 64 hhhhhhhhhmmmp – far from us to call them liars but as we have grown these under hid and led by a number of our group I can say for sure THIS IS NOT THE CASE. I suggest to sweet seeds that they put the true time to maturation on their seed packets as not to mislead their customers as I am sure this would be the last thing they would want 🙂

day 58 to harvest

Everything good we’ve switched the feed to bloom and I’m feeding on 20 mills of a and b. The Fero 4G grow light is now hovering at around 50 cm from the canopy. Up until flowering set we kept it at 1m and let the plant grow to it. This seemed to work well and its fantastic the way the node spaces have kept so even. With lots of pots the area is quite packed and some of the lower growth seems a little weak so I removed it to let the energy go into the larger top colas as I felt the number of plants combined with lots of “xmas tree” shape plants was cutting out the light at the bottom.

I have to admit at this time thing got a little more complicated as I had 3 different genos to work with which were obviously going to mature and develop at different rates The feed regime had to be adjusted for each particular geno so from this point on when the boost was administrated was very much based on each individual plants requirement. Thank god I was growing in pots in a soil less medium. I’ve always taken cuttings for NFT in the past, and because these aren’t possible with autoflowering plants (see “the worlds smallest marijuana plant), it does make me wonder about growing hydroponically with autoflowering marijuana.

We have received some criticism in the past for growing using auto strains as to be more scientific in our trials (hi reddit readers!). However we are as a group very interested in auto strains and the direction in which cannabis cultivation is moving. I’m currently trying to get a white widow auto strain ready for independent trial, and one thing which I think the seed strains need to concentrate on is not just the autoflowering aspect of any particular strain, but also the standardisation of the final plant. Cream Caramel is a great smoke but its too difficult to grow a number of plants with such variance in height and maturation rate. I could have got an autoflowering Chase (Flash Seeds) in in that time period with three times the yield.

There’s not a lot more to add for this grow, no dramas just VERY very slow. If I hadn’t grown the same variety under HID I’d suspect the LED light, but know this not to be the case. However the yield is good, it smells lovely and is a pleasant well stoned high. For those of you growing for medical marijuana reasons I’d also add its really nice for achy joints 🙂

We cropped in 3 different stages
day 90 1 mutant runt that hermied un weighed made into hash
day 90 6 plants shorter genos combined weight 180 grams dried and cured weight
day 100 5 plants combined weight 170g dried and cured
day 110 7 plants combined weight  283g dried and cured
day still waiting 1 plant 🙂 estimated weight 60 – 70 grams 🙂

7 days before plants harvested they were flushed with ph,d plain water to 5.6

As I had come to expect after having all my preconceptions about LED grow lights blasted by the Fero 4G 360, the Fero 18 worked well and did the job brilliantly. One thing I would say is that being such a large light it can be a little heavy adjusting the height. I’m not a small chap but it still made me a little nervous fiddling with the cables and maintaining the weight of such an expensive object over an expensive crop on my own. I think I would have been happier running two of the smaller lights over the same area. It easily met my expectations of 2 x 400 watt HID lights.

HOWEVER for anyone running a commercial sized grow using cuttings on NFT trays this system would work fantastically with great results. The amount of heat produced was minimal and there were no problems keeping an even temperature of 21ºC. In a cold snap where room temperature dropped extremely low I had to add additional heat for a week but this was mainly due to crap insulation in the room rather than anything else.

Once again I would recommend these lights as a serious contender for anyone thinking about buying an LED grow light system. I often see people asking for advice on forums about different brands and I can understand nervousness about choosing a “less well known” brand name. What I would say is that the Fero LED range deserves to be on anyone’s list of “possibles”: which light you buy will depend on price etc but if you ARE thinking of getting an LED system and want a recommendation, these ones get a big THUMBS UP from me. 🙂