How Many Plants In My Space

[Owderb]

This question keeps cropping up nigh on every week so this is how I look at it although there is no hard and fast rules. How you choose to grow also determines plant numbers and pot size. I.E Screen of green(scrog) or Sea of green (sog).

I think the easiest way to work out the best pot size and plant numbers is to first look at what bulb you are using, and I'm using hps bulbs as my base and a 3ft x 3ft or 4ft x 4ft space, and whether plant numbers are a concern for you or just not practical

Work out how many ounces that bulb could and will produce if your grow practices are good. Averaging 1grm/watt as a rough guide

EG..600grms = 21oz so if using 9 plants 600/9 = 66grms/plant which is just over 2oz. A 6.5ltr pot whether in compost or coco will produce that size of plant consistently if like I said earlier its grown in a good environment. I cant see the point of using big pots if only needing a couple of ounces per plant. By the time a large pot has rooted out the plant will probably be too big and you will have had to top or supercrop to keep the height down plus its just wasted time

If using 4 plants then you would look for them to yield over 5oz/plant so then you would need at least an 11-15ltr if in compost but you would get away with 11ltr in coco. Coco tends to out yield compost by more when you get to the bigger pots. Training would mostly be used for smaller numbers to fill the canopy

You also have to take into consideration vegging times. Obviously if you need a crop off quick then its no good using big pots because your vegging times would be longer so smaller pots would be the order of the day. Smaller pots are better also when height becomes a problem

If using sea of green then you could if practical fit 100 plants in there in 1ltr pots but it should still yield the same as 4 plants seeing its the light that governs your yield to a great extent but you would have no vegging time

At the moment I have a 1000w in a 4ft x 4ft space. Ive put 16 plants in coco in there and I'm looking at around 2oz per plant so chose 6.5 ltr pots

Ive also yielded 35oz out of 5 plants in 11ltrs of coco with run to waste watered once a day with a decent run off

So there's a few things that you need to look at before deciding, and then decide on what's practical for you

Hope this makes it a tad clearer

ED to add....This is not written with auto$ in mind

Owd

Edited October 6, 2016 by Owderb

[Guest cpt beefheart]

fuck thats a lot of light in there fair play dude

[Tony Montana]

As usual Owderb, very informative, clear and concise

Is it possible to Pin the thread so we can refer Members to it?

What height do you normally flower your plants at in a 6.5ltr pot?

Thanks

Gunner

[Owderb]

I usually flower when they are around 14-16" although strain can affect my decision

Owd

[jake212]

Thanks for the guide,Owderb

No end of help these guides of yours

[Arnold Layne]

Excellent post, my friend, very informative! I agree with you, completely. As you know, I follow pretty much the regime you are outlining here, and can say from experience .... you are bang on the money.

My grow space is smaller than yours, at 28" x 19", with about 4- 5 ft of headroom. I use a 250HPS or MH, and consistently get about 7.5 Oz per crop. Just short of the GPW mark, so I know more needs to be done to dial her in completely.

I'm seriously thinking about upgrading my light too. Maybe to 400 with a single HPS bulb. Or I might combine a 250HPS with some of those new tube type things, I forget their name right now. The ones you can get right close to t'plants, and which you can put into a household bulb holder. Eco-something or other I think?

Any thoughts, Owd? Do you think 400 would be alright, or is it overkill?

The reason I'm thinking down these lines is that I want to increase my yields. I could, and had planned to simply change my vegging 'drobe into a second flowering 'drobe. But that is costly, and would need a cash injection of around £300. I don't mind that so much, but figure ramping up my existing flowering 'drobe may be the better option as its not only cheaper but would also mean I don't need to source a new vegging chamber of some kind.

I await your usual wise council with anticipation. Opening up new grow ideas is such an exciting thing, I find.... Maybe we should have another coffee-morning, we three, and see what we see? My organisation skills are second to ..... well, just about everything really!

Edited February 21, 2011 by Arnold Layne

[Owderb]

I think a 400 in there Arnie would be a bit too much, plus you would have to upgrade fans and filter size. But it may just be worth having a play with an ecolight. The only problem I have with mixing cfl's and hps's is that the ecolights have to go virtually on top of the plants therefore blocking the light of the hps, but in your space it may just be worth a play

Orrrrrrrrrrrr...get a bit bigger space

Owd

[vbombs]

Hi Arnold ,im also a 250w hps grower and also thinking of upgrading

to 400,my main problem is heat in the Summer months,i think maybe

go 250 for Summer and change over to 400 in the colder months is

the way to go,them hopefully my envoirment will be up for it

Also thank you Owderb for the great info as always

Edited February 21, 2011 by vbombs

[chubbster]

I must admit that I am with Vbombs on this. I have just got my first grow in a 36" grow tent with a 250w HPS. My babies are vegging really nicely and I will be probably be flicking at the weekend

I have thought about upgrading to a 400HPS light as the filter/fan I have can cope with it. The big BUT for me is that the tent is in my bedroom as I only have a 1 bed flat. If I put a 400w HPS light in there for the summer months I would be frying if |I tried to sleep. So I am going to give a 400w HPS light a chance come my grow in the autumn. What do you guys think?

Chubbster

PS Cheers for the very useful info fella!

[Rogo]

Just wishing I had read this thread 3 weeks ago

I have a 600w in a space 6ft wide x 5ft high x 2ft deep.

Now getting major probs with heat.

Agree this should be pinned for total noobs like myself.

Thanks for the info

[stigz]

So in a 2.4 x 1.2 tent, with 3 x 600Ws giving 1800W of light, = 64oz. 10 plants in 15 litre pots is 6.4oz a plant!

I'd struggle to achieve that like. Would it be advisable to use more plants in smaller pots in order to achieve the full potential?

Maybe try and do 32 plants in 6.5 litre pots?

[stixx]

So in a 2.4 x 1.2 tent, with 3 x 600Ws giving 1800W of light, = 64oz. 10 plants in 15 litre pots is 6.4oz a plant!

I'd struggle to achieve that like. Would it be advisable to use more plants in smaller pots in order to achieve the full potential?

Maybe try and do 32 plants in 6.5 litre pots?

in that tent with those lights depending on the ammount of time you have available for vegging i would eith go the way you suggest or

18 plants in 11ltr pots

12 plants in 15-18ltr pots

there is a multitude of pot/plant variations its finding the one that suits your particular style of growing, the time you have available and how much work you want to do.

remember the more plants you grow the more you have to trim and the more chance CPS will throw production charges at you.

[FARMER G]

As said great thread Owd

i usually flower in 3.5ltr pots with the numbers around 7-8 plants depending on vars , my space is just under 3 x 3 if i remember correctly with around 4-5ft head room , i use a 400w hps for lighting , i would say my average yield to be around 350-375g`s so i guess i hit around 40-50g per plant depending as said on vars , i am currently using Scorg for my method of grow and its my first time aswell , growing out a 12 week LOT#5 in a 11 ltr pot and she`s huge ! do you guys think this will be ample enough for a reltivly ok yield if enviro factors are in place ? was thinking around 1oz per ltr of soil used ? any input or thoughts would be most welcome

FG :wink:

[stigz]

Still cant decide what to do, 6.4oz a plant is a bit of a task really. But i dont fancy having 30 odd plants, and i've spent a fair bit on my autopot setup.

Should I just turn off a light?

I normally put my plants into flower when they have rooted out their final pots, and so far they have ended up about 12-14 inches tall, in 15L pots. Should I veg them a bit longer for extra height?

Just got myself a ne MH bulb which should speed up and increase growth, and have sorted my temps out proper now.

help!

[persuit-of-potancy]

This question keeps cropping up nigh on every week so this is how I look at it although there is no hard and fast rules. How you choose to grow also determines plant numbers and pot size. I.E Screen of green(scrog) or Sea of green (sog).

I think the easiest way to work out the best pot size and plant numbers is to first look at what bulb you are using, and I'm using hps bulbs as my base and a 3ft x 3ft or 4ft x 4ft space, and whether plant numbers are a concern for you or just not practical

Work out how many ounces that bulb could and will produce if your grow practices are good. Averaging 1grm/watt as a rough guide

EG..600grms = 21oz so if using 9 plants 600/9 = 66grms/plant which is just over 2oz. A 6.5ltr pot whether in compost or coco will produce that size of plant consistently if like I said earlier its grown in a good environment. I cant see the point of using big pots if only needing a couple of ounces per plant. By the time a large pot has rooted out the plant will probably be too big and you will have had to top or supercrop to keep the height down plus its just wasted time

If using 4 plants then you would look for them to yield over 5oz/plant so then you would need at least an 11-15ltr if in compost but you would get away with 11ltr in coco. Coco tends to out yield compost by more when you get to the bigger pots. Training would mostly be used for smaller numbers to fill the canopy

You also have to take into consideration vegging times. Obviously if you need a crop off quick then its no good using big pots because your vegging times would be longer so smaller pots would be the order of the day. Smaller pots are better also when height becomes a problem

If using sea of green then you could if practical fit 100 plants in there in 1ltr pots but it should still yield the same as 4 plants seeing its the light that governs your yield to a great extent but you would have no vegging time

At the moment I have a 1000w in a 4ft x 4ft space. Ive put 16 plants in coco in there and I'm looking at around 2oz per plant so chose 6.5 ltr pots

So there's a few things that you need to look at before deciding, and then decide on what's practical for you

Hope this makes it a tad clearer

Owd

sorry owd that was excellent info,

but do you know what the figures would be if you change to using an iws instead of coco/compost in 2m x 1.2 dr240w tent with 2 600w hps, 18 pots fits in snuggly but i think they might need a little more room so was thinkin of using 12 pots, which would give me the best yeild in shortest lenghth of time using 8 week flowerers.

thank you owd.