LED Grow Light Forum

Hi,

hope someone will be able to answer me

here at nite it get's real cold like - 5°F --- 0°F

there is not enough heat coming from the LED
does someone have same problem ? do you have suggestion?

the temperature that I have at nite is around 65°F and day time it is around 77°- 82°F

second question please:

I read that the plants de not recognize the color green
if so is it bad* when they sleep to have a green light on 15mins every hour during dark time?

thank you for your answer suggestions

are you in vegetative or flowering stage of growth?

what are your humidity levels?

second question, you can use a green light ( a green LED is best, not a white LED painted green or a green CFL). but only use it if you have to check on the plants for an emergency. definitely not every 15 minutes, every hour, every day, etc.

RKY

thank you rkymtnman, for answering me

I understand for the green light will use it only for emergency

the flowering tent is 40-45% humitity with day time temp between 74-80°F

for the vege tent they are at 70-80% humidity and temp daytime is 80-82°F

it is at nite time that I have a problem the temp goes down too much
but I've been told I can put a little heater with a control that will start when it gets cold

I will go and get myself 2 little one with 2 timer like that I think it will solve the problem

I hope that the past 5-7days of yoyo temperature did not affect them too much

Been told also that the temperature need to be between 80-85°F (25-30°C )
in all time flowering or vege mode because I am using LED
compare to 20-25°C (68°-77°F) for all the other lamps. do you agree on that?

thanks again for your answer

rkymtnman wrote:are you in vegetative or flowering stage of growth?

what are your humidity levels?

second question, you can use a green light ( a green LED is best, not a white LED painted green or a green CFL). but only use it if you have to check on the plants for an emergency. definitely not every 15 minutes, every hour, every day, etc.

RKY

no problem.

your temps and humidity look good.

the only thing i would add is that you want about a 10 degree difference between nite and day temps for flowering.

for vegging, a constant temp is best.

i think the range of 70 to 85 is OK for the plants. most strains and plants are pretty flexible as long as they don't get much out of that 70 to 85 range.

did you say you were from France? i used to do alot of work in Petersbach if you know where that is

RKY

hi again thank you for answering me I appreciate it a lot

so for me there is no reason to stress as the temperature in flower mode day time temps stays around 75-78°F
nite time it goes down around 70 so I AM all good no need to get a heater........this is great

vege time I do need to get a heater as it does drop like 10 degrees

when you say a range of 70-85 F is OK it's for all mode or just flower?

the vege mode I am trying to keep it at 80°F and humidity at 70%
is that too much?


nope I am french from Quebec Canada my friend thanks again for your help

rkymtnman wrote:no problem.

your temps and humidity look good.

the only thing i would add is that you want about a 10 degree difference between nite and day temps for flowering.

for vegging, a constant temp is best.

i think the range of 70 to 85 is OK for the plants. most strains and plants are pretty flexible as long as they don't get much out of that 70 to 85 range.

did you say you were from France? i used to do alot of work in Petersbach if you know where that is

RKY

thanks to ed rosenthal:

Temperature, Humidity & Air Quality

Marijuana grows well in moderate temperatures – between 70° and 85° F (21°-29° C). Both high and low temperatures slow marijuana’s rate of metabolism and growth. Plants grow fastest when the temperature during the lighted period is kept between 72° and 77° F (22°-26° C). When CO2 is being used, the plant prefers to be a few degrees warmer, between 79° and 85° F (26°-29° C). Individual marijuana varieties differ in their temperature preferences by a few degrees, so some experimentation is required to find the ideal temperatures for the strain you are growing.

Ideal temperature is tied to light conditions. As more light is available, the ideal temperature for normal plant growth increases. Strong light and low temperatures slow growth and decrease stem elongation. Conversely, when plants are given high temperatures and only moderate light, the stems elongate.

Plants growing under moderate intensity lamps (40-50 watts per sq ft, 430-540 watt per sq m) should be kept on the low side of the recommended temperature range. Plants growing under higher intensity lamps (60 watts per sq ft, 650 watts per sq m and higher) should be kept on the warmer end of the scale.

During dark periods, the temperature can be kept as much as 10˚ F (-12˚ C) cooler than the lit period without any negative effects. Wider temperature differences cause slower growth, stem elongation and delayed flower ripening.

Plants that are kept at a constant temperature are likely to grow stouter, sturdier stems and have denser bud growth. Plants that experience a large differential between day and night temperatures suffer from stretching and slowed growth rates.

At temperatures below 60° F (15° C), photosynthesis and plant metabolism slow, stopping growth as it waits for better conditions. As soon as the temperature rises, the plant resumes full functioning. When the temperature falls below 40° F (4° C), marijuana plants experience tissue damage and require about 24 hours of warmer conditions to resume growth. Young marijuana plants are somewhat tolerant of low temperatures; when outdoors, seedlings have been known to pierce snow cover without ill effect. But low temperatures during ripening, even just overnight, delay or prevent bud maturation. Some equatorial varieties stop growth after a few nights with temperatures below 40° F (4° C).

au revoir!
RKY

well thanks again for all those infos rkymtnman

I do appreciate it... those are the preference for plants under HSP
all that I read mention that under LED lants needs to be 10 degrees higher

since you are the pro's here is that real?

and in both mode humidity should be all the time around 40% as there is less evaporation since the led do not heat up?

like it says in this video
(No links until you have more posts: Please read the rules on posting links.

sorry if i ask lots of questions I want to do my best for my sweeties

the use of CO2 is it important since I only have 4 plants and checking the pph ?

I am growing for me so I am more looking for special brand then quantities

good day

I've never heard that LED should be 10 degrees warmer. It also depends on strain. Some like warmer, some cooler.

Just keep it between 70 and 85 and you should be fine.

Your humidity levels are about perfect.

Don't know about CO2. I don't use it. You really need a sealed environment to make full use of it.

hello again
I would not bother with the CO2 for the moment

just to bring them to term will be my challenge for the moment making sure they have all they need

if you listen to the video you will hear his reasons for a 10 + degree

I just bought a indoor outdoor meteo station it will help me knowing the real temp at nite

you've been very helpfull

are you in a cold winter area?

rkymtnman wrote:I've never heard that LED should be 10 degrees warmer. It also depends on strain. Some like warmer, some cooler.

Just keep it between 70 and 85 and you should be fine.

Your humidity levels are about perfect.

Don't know about CO2. I don't use it. You really need a sealed environment to make full use of it.

oh yeah. colorado mountains. almost 3000 meters up. but over 300 days of sun so it's not as cold as the temps indicate. i can be outside in a tshirt in 30 degrees if the sun is out.

start simple. and then try to improve a little at a time.

i'd rather have quality vs quantity. the ultimate goal is to have alot of really good weed!