Propagating Thuja Green Giant Arborvitae
Hello, I have a rather long question - if you wouldn't mind taking a look and letting me know what you think...
I am new to propagation and on Sunday Sept 18th I made my first attempt. I chose Thuja Green Giant Arborvitae as I have heard Arborvitae are quite easy to root.
I cut stems 4"-10" in length, placed them in 0.5% IBA (Dip 'N Grow) for 5 seconds, stuck them in moist peat and perlite (2:1) then put them inside with a plastic covering over them. I left them in a room heated to 75 degrees and the soil has hovered between 70-75 degrees. I have lifted the plastic 3 times a day for ventilation purposes.
I am misting about 3 times a day and have put a one tube fluorescent light 6" above the trees at night for 12 hours. I just read that these trees can be propagated under normal day/night light without lights so I stopped switching the fluorescent lights on last night.
Today I bought a Sunbeam heater blanket that has 10 settings and am using it as a less expensive solution to bottom heat as it covers a much larger area than most seedling heater mats I have seen. I am aiming for between 75-85 degrees bottom heat.
I am hopefully expecting roots to form after 6 weeks.
My question is:
I looked at the foliage tonight and 20-30% of it is turning brown at the edges. What am I doing wrong and how can I make sure the foliage remains green?
Thank you for any comments you may have.