Greenhouse query

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
Hello everyone

Can anyone help me with a question (or 2) about growing in my back garden greenhouse??

I have 9 plants (superskunk) that have been growing in my back garden for about a month now, they're about a foot tall and look reasonably healthy, I've got them in some nice soil with about 5% wormcast. At the moment they're outside, it's hot enough here in the summer to grow them there, there'll be no rain until after the summer now.

I'm paranoid about them being seen but more worried about the smell, the best place for light in my garden is next to my neighbours fence! At the moment that's not really an issue but it will be come late august - early september when I hope they'll flower. Also on the seed packet it suggested that yield could be increased if the plants were grown in a greenhouse.

My questions to the knowledgeable are:

1) will it be too hot in the greenhouse? it will get to over 40 here somedays
2) will the lack of CO2 be a problem? I'm trying to do this cheap!!
3) will a fan be sufficient ventilation?
4) is there any problem with moving the plants into the greenhouse for the flowering stage??

Any help would be great

Sombro
 

GanjaGuru

Well-Known Member
Joined
May 26, 2005
Messages
1,209
Reaction score
129
I don't know the size of your greenhouse but I'd think it would be a definate plus to install some flo-thru ventilation. Enough for a gentle breeze would do.

As far as the smell goes, any indication that your neighbors know what growing pot smells like (often it doesn't smell like for instance pot in a bag)?
Some growers I know faced with a similiar circumstance plant strong-smelling herb & flowers such as garlic and carnations near their pot plants.
They also put plastic flowers and berries on their pot plants in case someone peeks over the fence.
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
thanks man

the house next door is a summer home and theres a chance that they won't be around come october.

i'll plant some stinky stuff nearby just in case.

i read that mj stops growing if the heat gets to be above about 30, well its that every day now, will the heat in the greenhouse (i guess it'll get to over 50) affect the growth do you think??

thanks again.
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
oh and ps love the plastic flowers idea.
 

GanjaGuru

Well-Known Member
Joined
May 26, 2005
Messages
1,209
Reaction score
129
Marijuana stops growing at temps over 100F.

I don't what that equal's in C.
 

Hick

Git "R" lit
Joined
Apr 19, 2005
Messages
12,835
Reaction score
12,613
40C is slightly over 100F, but I would tend to believe, with plenty of flow through venting, you could be OK. Possibly look into one of those "misting" devices to aid in cooling just a little. Would also raise humidity, if that could be a problem.
http://www.microcool.com/cooling/index.shtml
 

GanjaGuru

Well-Known Member
Joined
May 26, 2005
Messages
1,209
Reaction score
129
"Possibly look into one of those "misting" devices to aid in cooling just a little."

I hate to nit-pick my good friend, but the only way that would work (misting with water) is if the water were cooled before misting.

I clicked on the link provided and it certainly sounds like sci-babble. Like it says spraying what looks to be scores of gallons of water in a certain location doesn't raise humidity.

Water (sweat) cools people if the water temp is below 98.6F. Nature is always trying to equalize things, and the heat from the body is drawn into the water, which then evaporates. Air movement (wind/fan) accelerates this process.
Water cooler than a creatures core body temp will cool any animal, but I don't think water cools air unless it has been cooled to a temp lower than the air temp.

And I think misting in an enclosed space like a greenhouse would cause the humidity to skyrocket, like a bathroom after you've taken a shower.
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
cheers for the advice


i guess that plenty of flow through air would mean plenty of smell escaping too, i reckon i'll move them indoors in early september when the most fierce part of the summer is over and the heat shouldn't be a problem.
 

Hick

Git "R" lit
Joined
Apr 19, 2005
Messages
12,835
Reaction score
12,613
"Nit-pickin'"...;) hee e.. I dunno' the principle behind it, but AZ is loaded with them. Beer gardens, around pools, houses, decks. And they do cool the immeadiate area to some extent. I agree, humidity would soar, but with my thoughts were that the flow through should control that.
BUT, I see your point, and my lack of foresight.
Water (sweat) cools people if the water temp is below 98.6F.
cools people through condensation, but "plants" ain't people.
I've certainly never attempted this scenario, but was kinda' "brainstorming" it.
 
S

Stoney Bud

Guest
Hick said:
"Nit-pickin'"...;) hee e.. I dunno' the principle behind it, but AZ is loaded with them. Beer gardens, around pools, houses, decks. And they do cool the immediate area to some extent. I agree, humidity would soar, but with my thoughts were that the flow through should control that.
Hey Hick, yes, they do cool great. The simple principle is that the water droplets absorb the heat and then either carry it to the ground, a collection surface or a strong ventilation exhaust.

The water only needs to be at 85 degrees F, or lower. Any ambient temperature over that will be absorbed and moved out of the greenhouse.

The spray shouldn't be continuous. If it is, then you will run into a bad humidity problem. Any intermittent spray that is adjusted to keep the temp at a high of 85F is all that's needed. If the spray is applied every ten minutes for 2 minutes, it's sufficient to cool the greenhouse.

I've had a greenhouse for 10 years and it gets to over 100 every year. Using the misting system, it's never gotten over 85 in it.

The plants love the extra humidity and the continuous strong air flow. There is a balance that has to be met when using this system and misting failure can result in fast plant damage. I always use dual pumps set to alternate sprays. I've had one go out, but had no damage because of the second pump.

My greenhouse only has garden veggies in it, but the same temp requirements are met.
 

Hick

Git "R" lit
Joined
Apr 19, 2005
Messages
12,835
Reaction score
12,613
Well thanks stoney!!! Like I said, I'm not sure of the principle involved other than condensation, but most certainly felt the difference in temps myself around the "veranda" in Tuscon. It occasionally gets warm down that way too. Just wasn't positive that it would have the same effect on plants. Questioning differences in transpiration, condensation and prespiration...
Glad to recieve some "first hand" info..
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
thanks gents

i reckon that the misting device might be a bit complicated and/or expensive for my first effort but it's definately worth considering for the future.

i read in a grow guide that in a hot ,dry climate such as this one a greenhouse can help prevent the rapid evaporation of water from the pot as the humidity would be increased by the plants themselves. I started watering once every two days but they started to wilt, they look much happier now i'm watering every day but i'm sure its better for the plant if it doesn't have to fight the evaporation process to get at the water.

sombro
 

GanjaGuru

Well-Known Member
Joined
May 26, 2005
Messages
1,209
Reaction score
129
Stoney Bud:
What's your water source for your misting system?
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
update:

ok the greenhouse has arrived, i'm going to buy a desk fan and a max/min thermometer to see how hot it gets in there with or without ventilation before i put the plants in, to be fair they seem quite happy in the open air. I think i'll stick with the plan to put them in the greenhouse for the flowering stage.

I bought a misting device but at the moment its being used to help baby sombro breathe easier.

oh and apples from the garden that have ripened early look at a glance like tomatoes, could be some decent camo there.

peace.
 

Hick

Git "R" lit
Joined
Apr 19, 2005
Messages
12,835
Reaction score
12,613
"Cool" sombro...'literally!..;) hee hee. Glad that baby Som is enjoying the mister at least :).
Question on your "moving them?" question. Are they in pots?..If not, moving them is going to be "difficult" at best, if not impossible by Sept. The roots will be far too reaching o dig and relocate them without at least severely shocking or more likely, killing them.
I'me not an experienced GH grower, but just as with an indoor op, I would suggest try useing the fan for extraction. Removing the hot air, allowing for passive intake. A desk fan may not supply the cfm's needed.
 
S

Stoney Bud

Guest
Hick said:
Question on your "moving them?" question. Are they in pots?..If not, moving them is going to be "difficult" at best, if not impossible by Sept. The roots will be far too reaching o dig and relocate them without at least severely shocking or more likely, killing them.
Moving plants from pots to Hydro is difficult. I've seen professionals in a lab environment screw it up. The method I've seen that is most successful is to wait until the plants are almost dry and while holding your hand flat against the top of the dirt with the stem between your middle fingers, turn the pot upside-down. Very, very gently, flex the pot a little on alternating sides until you feel the weight of the plant transfer to your hand as it drops from the pot. Remove the pot very slowly making sure the roots have all let go.

Now comes the most difficult part; put the plant on it's side, onto a clean, smooth surface that you can pour lots of water onto. Place the top of the plant on something that will keep it dry and out of the water you'll be using. While holding the root ball, start very slowly to soak the root mass with water. Start at the very bottom of the root mass. The end that is on the bottom when the plant is in the pot standing up. Soak it and gently move the roots with only the water until you have washed away ALL of he dirt and are left only clean roots. Do this until the entire root mass is free and clean. Then, you can form a piece of rockwool to fit your plants new home. Hollow out the rockwool so that the entire mass of roots will fit into the new rockwool plug with the stem sticking out of the appropriate area. Gently place it into it's new home and secure it so it cannot move. Water it until it's completely soaked.

You'll need to run your pumps to soak the root mass at least once an hour until you see roots starting to grow from the rockwool. With weed, it should do so in about one to two weeks from transplanting.

After your transplanting, the plants will wilt. This method of transplanting is one of the most traumatic methods used and really shouldn't be used unless you have no choice and you accept the risk of losing one or more of your plants.

Good luck to you and if you have any questions about this method, just post your questions.
 

sombro

Time Waster
Joined
Jun 6, 2006
Messages
163
Reaction score
11
cheers man

i'll think some more about the airflow setup.

they are in big pots and won't be a problem to move but at the mo they don't smell too bad and with the gh assembled they are all but hidden from view. they're getting plenty of co2 and the infrequent stiff breeze is making the stems nice and strong and thick.

I reckon i'll stick with the plan to move them into the gh towards the end of august when flowering hopefully will have begun and the temperature will have dropped to below 100.

now to convince mrs sombro that she can't use the greenhouse until november!!
 

Latest posts

Top