A 6x12 greenhouse? You are planning on cramming it to the rafters with weed right?
First of all, I probably would not bother with the cfl's - they are going to add an insignificant amount of illumination compared to all the sunlight. Only the leaves within 3-6 inches of a flourescent bulb get any benefit from the bulb so why bother?
3 gallon or 5 gallon square containers? (You lose 20% of you floorspace if you use round pots).
You have to be able to move around the floor of the gro op to water and inspect the plants. If you crowd them too close together it makes it really hard to water and inpect for nutrient deficiencies - unavoidably somebody will get neglected. Also, for me, it is nice to have some shelves to use for storage of supplies and equipment (like a co2 generator - definitely get yourself a co2 generator - you can almost double the rate of growth.)
Also, if you crowd them too close together, it is hard to move them around and you will end up breaking branches and causing other damage.
Assuming that you leave enough room to work conveniently in your greenhouse, you could easily set up 16 BIG plants in there (a five gallon bucket is 15" across; two rows of 8 five gallon buckets would just about fill 'er up)
I noticed that you only have a few autos in your seed order - those are going to do well and you'll have some good smoke in 2-3 months.
I think that you are going to be unnecessarily taking a very serious risk by planning such a long grow with photoperiods. You could easily avoid the risk of a disastrous crop failure and set up a perpetually harvest of autos.
You are Down Under right? Your Spring starts next month, so your Autumn equinox is not going to happen until next March, so that means that (9-14 weeks later) you can harvest in ... May, 2013? Are you prepared to wait 8-9 loooooooong months before all those photoperiods yield a harvest? Do you really want to do that? Planning on staying in town for the next nine months, are ya? Alot of things can go wrong in eight months.
And what if something goes wrong? If anything goes wrong, you risk wasting alot of time and valuable seeds.
Most of those seeds you listed are indica hybrids. Indica hybrid photoperiods were designed for a 3-5 month grow operaton. I doubt that you are going to get much benefit by stretching it out so long.
Why not just grow autos?
Does your greenhouse has glass or plastic roof? Either way, glass and plastic both effectively screen out ultraviolet light. You will lose alot of essential oils by depriving the plants of uv.
But if you do not have a roof, altho you increase the exposure to pests, at least they get hit with uv (google "UV index" for the various months of your grow - the higher the better for MJ). If I were you I'd shitcan those cfl's and get some t8 10.0 lizard lights for supplemental lighting inside the greenhouse. Learn about uvb on the internet - it can be dangerous but it makes a huge difference in the quality of the weed.
That's my .02!
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