This ‘BC Big Bud’ is a week from harvest.

Light

Above each table hang eight 430w Son-T-Agro HPS lamps in the “high-tech” grow show. The lights are so crowded and heat such a problem that only six lamps are turned on. There are a total of 24, 430w lamps in each room, 48 lamps in both rooms could provide for a total output in watts of 20, 640. If each lamp uses about 5 amperes of electricity, they need at least 300 amperes of incoming electrical service. The total amperage used by the 48 lamps adds up to 240, but to operate the lamps safely, they should have 20 percent more amperage available.

Only 6 lights are used over each bed providing 51.6 watts per square foot of actual growing area (6 x 430 = 2,580w per 50 square foot NFT system). Much of the light, that could be used to grow plants, falls on the floor, unused!

I took an inexpensive light meter out of my camera bag. The meter registers in foot-candles and there is no correction for the HP sodium light spectrum. But that did not matter. All I needed to know was the intensity of light, nothing more.

I held the meter about a foot directly under an 18-inch mirror-finish reflector and moved it back and forth to measure relative light output in a two-foot radius.

“How do you explain that light in the two-foot radius 12 inches under the bulb varies by 50 percent? The plants are the same size but some of them get half as much light. What is wrong with this picture?” I asked.

One grower gave a blank stare. The other assured me that it was the light spectrum!

‘Champaign’ is a favorite in Vancouver, BC.

‘Champaign’ bud stripped of large leaves before harvest.

“If one plant gets half as much light as another only one foot away, it should be half again as big!” I lambasted. “It’s got nothing to do with the light spectrum and everything to do with heat, humidity and imbalanced nutrient solution”.

To power 48, 430w lights, the growers had to install a new breaker box that supplies 200 amperes of electricity. They brought in more electricity to run the lights but heat generated by the HIDs makes it impossible to use 25 percent of the bulbs that hang above each grow system. Not only is the extra electricity unable to be used, much of the light generated falls on the floor rather than on plants.

Lighting in the other three rooms was right on. One of the rooms used three 1000w metal halides, another a 6 1000w metal halides and 6 1000w HPS and the third, a combination of 40, 400w metal halides and HP sodiums. The horizontal hoods supplied a maximum of light and created no excessive heat.

The pots were packed together like sardines under the lamps. There was not one ray of wasted light.

This cool dark room is packed with more than 35 pounds of drying bud.

Summary

Most of the problems caused in the “high-tech” grow show were initiated by the 85 to 90 degree F ambient room temperature and 70 percent + relative humidity. The other half of the problems are caused by the “high-tech” hydroponic system and the (saline) nutrient solution. Growth essentially stops when the temperature rises above 85 degrees F. The heat causes poor nutrient use within plant tissue. Potassium deficiency is the most pronounced. This condition is compounded by high salinity in the root zone. In fact the temperature within plant tissue can rise much higher than room temperature, essentially cooking leaves from the inside out. The plant tries to dissipate the temperature through transpiration, but is stifled by high humidity. This is why leaves burn cup up and turn brittle.

The “high-tech” rooms cost $65,000 US to set up, about $2,700 for each 430w lamp. They should have cost no more than $20,000 to set up even if they bought the best of everything! The growers spent $45,000 more than necessary and by spending the extra money to go “high-tech” they created many problems they had to spend more money to solve!

The dream was 20 pounds a month. The actual facts show a miserable money pit. Harvest of dried manicured buds from both “high-tech” rooms was only 6 pounds of third-rate buds per month – Two pounds per table every 8 weeks. A little math shows that the cost of producing the first 6 pounds (excluding electricity) was about $10,000 per pound! If we multiply the 6 pounds times 12 months, a total of 72 pounds is produced in one year. Excluding the cost of electricity, at the end of the year the cost to produce each pound would be $900! Somebody should let these guys run the DEA! They would get about the same amount of bang for their buck!

The other three rooms were very simple had few problems. The growers concentrated on growing plants rather than spending and making money. Problems were avoided or solved before they occurred. By paying attention to the basics and having very few things to go wrong, made problem solving a snap. All three rooms yielded right at 0.5 grams of dried bud per watt of light every thirty days. The cost to set up each room ranged from $5,000 for the three-lamp (3000-watt) garden to $25,000 for the 40-lamp (16,000-watt) one. Including all of the supplies, the cost of setting up each 400w lamp was about $650.

Jorge Cervantes is the author of the recently revised Indoor Marijuana Horticulture (the Indoor Bible), Marijuana Indoors: Five Easy Gardens, Marijuana Outdoors: Guerilla Growing and countless articles. His works are published in Dutch, English, French, German and Spanish.

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