best humidity for rooting clones?

raggyb

Well-Known Member
I've got more control over my humidity to try and solve my cloning issues and want your advice. I've been lucky if half of my cuttings make it. Read a lot of suggestions and often see people saying to take the humidity dome off after only 1-3 days. I took my dome off this time and they're in about 60% humidity but a few of them are showing problems bending over at the top like their heading to death's door, lol, you know what I mean?

Some more info. Cuttings were semi hard woody lowers off reveg's, I know that increases difficulty. I cut em, razor scraped and dipped in clonex and root powder. Put them in seedling tray dome with Riot plugs. Added tap and put dome on for 6 days. Was too hot first 6 day so I switched lights to one 20W led bulb 10" above, and makeshift covered with a white pillow case between light and cuttings to dull the light but allow airflow. Temps 79F, rH 63%. Changed water after 6 days.

My primary question is- has anyone determined the perfect rH for rooting? I haven't seen that % posted anywhere. Should I go higher? In prior attempts I've seen the 100% humidity result in mold/damping and dying, but I've actually had more luck leaving the dome on with vents closed at 98 - 100%, as long as they don't get mold. It never takes mine less than 3 weeks this way. I've also lost some that had good roots after transitioning to soil. So again, isn't there any evidence on the best rH% for rooting?
 

Jjgrow420

Well-Known Member
i put an airline and airstone inside my dome and keep it closed. i dial down the air so that its coming out slow and that keeps fresh air moving through the dome. sometimes im busy and i dont even touch the dome for days and everythings great inside. after 3-4 days you want them to begin to dry out and the rh to lower. it makes them think if they dont grow roots fast they gona die. once that process starts i close the vents again and bring rh back up for remaining days and roots will form fast
ill get roots in 5-10 days depend on strain
 

Jjgrow420

Well-Known Member
you can combat mold with a wee bit of h2o2 either spray it on or use it in the water at the bottom. dont let the cuts sit in water. best to elevate them with a tray that holds cubes. then you pour water into the bottom of the dome tray with h2o2 and airstone. the tray holding the cuts keeps them above the water line so they dont saturate.
 

Johnny Lawrence

Well-Known Member
Leave the dome on with vents closed for 2 to 3 days. Open the dome a couple times per day to exchange air and if needed, respray the dome.

On day 3 or 4 start opening the vents a bit. In my experience, it's okay to pull the dome off day 8 or 9. If any start to droop over, put the dome back on and check again the next day.

I also run a tiny bit of water in the bottom tray to get the humidity up more.
 

Johnny Lawrence

Well-Known Member
you can combat mold with a wee bit of h2o2 either spray it on or use it in the water at the bottom. dont let the cuts sit in water. best to elevate them with a tray that holds cubes. then you pour water into the bottom of the dome tray with h2o2 and airstone. the tray holding the cuts keeps them above the water line so they dont saturate.
^ this
 

Star Dog

Well-Known Member
There's something well fucked up if you need to resort to h2o2 to prevent mould in a propagator.

I've got around 97% success rate putting them in a clone tent with 50/65% rh or whatever the local rh% is.
Coco, root riot plugs and a bubble cloner all produce good roots without all the palaver of high humidity, spraying etc.
 

raggyb

Well-Known Member
i put an airline and airstone inside my dome and keep it closed. i dial down the air so that its coming out slow and that keeps fresh air moving through the dome. sometimes im busy and i dont even touch the dome for days and everythings great inside. after 3-4 days you want them to begin to dry out and the rh to lower. it makes them think if they dont grow roots fast they gona die. once that process starts i close the vents again and bring rh back up for remaining days and roots will form fast
ill get roots in 5-10 days depend on strain
Nice method. Sounds like from what you say I could have less h2o from the tray.
I think I got rH between 89% and 91% with fan evacuating every 5 min. I'm not sure I can push it higher. Do you think she'll pick up?
 

raggyb

Well-Known Member
Humidity at 1 foot up is 94-96% and down at ground/cut level reads 99%. After 12 hours it may be early to say but they might be perking up.
 

goofy81

Well-Known Member
Higher is better yes,
However lower works fine too, just takes longer. Just spray mist on them whenever you're in the room.
I've made clones with 40% humidity but sometimes it takes 2-3 weeks (not in a hurry since I have 8 weeks of flower time).

I have about 95% success with my clones and the 5% failure is mainly carelesness. If you're failing alot it could be your method of cloning.
I also clone in straight coco and keep it moist all the time before it roots.
 

kingromano

Well-Known Member
100% is too high
you want some fog on the glass but not too much
when it start to condensate on plant leaves it's too humid

i wasted trays of rockwool with too much RH
 
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