[general_war]

hello everybody, long time lurker here, also growing outdoors for the last 7 years. NO experience indoor.
that's where the problem lies. in the last two years, my seedlings got f***** by low temps, even though placed in pots in a greenhouse. they died. 100%.

so, for the coming season i'm planning to make a growroom, just for starting the seedlings until late may or so. i'm looking for a setup for 25 pots (15x15x20cm) - that means i have to provide light for approx 0,6 - 0,7 m2.

my questions are:
1. one 250W mh vs. multiple (10-12, even more?) 20W cfls (6500k), equally distributed?
2. in late may, i get approx. 15 hours of daylight (16 hours between civil twilights). what light cycle should i grow them on? 18/6, 16/8, 15/9, so they dont star flowering early when moved out?
3. when should i start them (especially if i have to use 15/9 cycle)? a month /two months prior to moving them out?

Please help, i don't want to just browse growing forums all summer because my girls got killed again

[BOMBAYCAT]

I normally start my seeds (600 watt HPS) in late March indoors, then move them outside in late May. This gives me a chance to presex before they go outside. The plants also get a chance for vegging that way and are a decent size before the bugs chew on them and etc. It takes up to 6 months to get a run that way. I am doing a quick run now (fall/winter) to get some F2 seeds and go treasure hunting for Phenos. I am planning on this run to last 3-4 months in this climate as I live near the mountains so the growing season is shorter.

[general_war]

Originally Posted by BOMBAYCAT

I normally start my seeds (600 watt HPS) in late March indoors, then move them outside in late May. This gives me a chance to presex before they go outside. The plants also get a chance for vegging that way and are a decent size before the bugs chew on them and etc. It takes up to 6 months to get a run that way. I am doing a quick run now (fall/winter) to get some F2 seeds and go treasure hunting for Phenos. I am planning on this run to last 3-4 months in this climate as I live near the mountains so the growing season is shorter.

what is your light cycle? i think it has to be more or less syncronised with daytime whe you put them outdoors.

[thejact55]

I just veg 24 hrs light, then toss em out middle of may. I normally start march also. No issues, hermies or anything. Bombay cat is bang on in his comment too.
Id go with the 250, but hell add some extra lighting cfls, why not?
Once the plant is a foot or so tall and presexed you should be fine in most occasions.
Those T5 cfl panels work good for veg too. If your not flowering, that would work too. Bigger is better though

I dont worry one bit about syncing with outside light. Do all indoor growers mimic the outdoor light cycle? Rarely, only those with a dope timer/ballast. They go 24 hrs or 18/6, then boom 12/12 or less. Kinda the same concept. Ive never had a plant flower on me in may. If it was , it would simply reveg in june or july.

Edit- missed the amount of pots. for 25 pots, i personally think you need a 600 at least. Lets say you put them in one gallon pots. I can cram i think 16 pots in my 3x3 tent. You would need like a 4x4 coverage, a 250 isnt much light for that.

[BOMBAYCAT]

The light cycle is the standard 18 for vegging indoors. When I put them outside they might get a little confused because of the short daylight (try to go into flower) but they come out of it in a week or two and go back into veg the way they are supposed to with no problems. I have used the "daylight hours explorer" before. You need to know the Lat/Long of where your are growing and it gives the exact hours of daylight at a certain calendar date. You then try to match the outside hours of daylight by putting the plants outside a little bit later. It seems to work for me if I just put out the plants at the end of May. Another thing is the plants can actually get sunburn. I just shade them with a piece of board for a couple days to harden off. That URL I have for the daylight hours explorer doesn't work or I would pass it on. It is fun to play with.

[~star~crash~]

Originally Posted by BOMBAYCAT

I normally start my seeds (600 watt HPS) in late March indoors, then move them outside in late May. This gives me a chance to presex before they go outside. The plants also get a chance for vegging that way and are a decent size before the bugs chew on them and etc. It takes up to 6 months to get a run that way. I am doing a quick run now (fall/winter) to get some F2 seeds and go treasure hunting for Phenos. I am planning on this run to last 3-4 months in this climate as I live near the mountains so the growing season is shorter.

Hey Bombay what is your method for pre-sexing your crop? ...peace

[general_war]

Originally Posted by thejact55

Edit- missed the amount of pots. for 25 pots, i personally think you need a 600 at least. Lets say you put them in one gallon pots. I can cram i think 16 pots in my 3x3 tent. You would need like a 4x4 coverage, a 250 isnt much light for that.

ok, thanks. i don't think i'll bother with a 600w. i thought i could veg them under a 250, but 600 is a whole other level, especially since i have no experience.
although i think if you put the pots in 5 rows with 5 pots each, one next to another, you get 2,5 x 2,5 square feet, (since pots are 6 x 6 inch). do they have to have space between them? i think in one month under a 250w mh with a couple of cfls thrown in, they won't get too big.

[general_war]

Originally Posted by BOMBAYCAT

The light cycle is the standard 18 for vegging indoors. When I put them outside they might get a little confused because of the short daylight (try to go into flower) but they come out of it in a week or two and go back into veg the way they are supposed to with no problems. I have used the "daylight hours explorer" before. You need to know the Lat/Long of where your are growing and it gives the exact hours of daylight at a certain calendar date. You then try to match the outside hours of daylight by putting the plants outside a little bit later. It seems to work for me if I just put out the plants at the end of May. Another thing is the plants can actually get sunburn. I just shade them with a piece of board for a couple days to harden off. That URL I have for the daylight hours explorer doesn't work or I would pass it on. It is fun to play with.

thanks. i know you'd have to strenghten the plants before putting them outdoors.

i think this kind of online programme is usually called sun calculator or something like that

[thejact55]

Originally Posted by general_war

ok, thanks. i don't think i'll bother with a 600w. i thought i could veg them under a 250, but 600 is a whole other level, especially since i have no experience.
although i think if you put the pots in 5 rows with 5 pots each, one next to another, you get 2,5 x 2,5 square feet, (since pots are 6 x 6 inch). do they have to have space between them? i think in one month under a 250w mh with a couple of cfls thrown in, they won't get too big.

Theyll be fine, especially with cfls to supplement. If for some reason the 250 doesnt cover the area well, they could be somewhat stetchy due to lack of light. The sunlight through summer months might help, but they might be lanky when first put outdoors. No space is needed between pots really for temporary veg. Pack em in.

Fyi- presexing occurs naturally no matter what light cycle. When they are mature enough to flower they will throw a little ball and be male or pistils meaning female. No method here really.

[~star~crash~]

you cant hold a crop long enough in small containers for them to pre sex naturally ... it takes way too long ...we need seedlings sexed is what i'm asking about ...peace