I decided this fall to see how well I could grow acer palmatum seedlings under a HID metal halide grow light. I have been pleased with the vigor of the growth. The system is a 1000W Metal Halide that I used previously for orchids. My intention is to choose a couple of plants and grow them exclusively under the growlight (placing them in a fridge or garage for 12 weeks each winter for dormancy). Just an experiment to see how they will do without ever seeing the sun. The photos are of seedlings from seeds harvested at the local library in Sept 06 they have been under the light about 10 weeks Keith
Hello Keith, i am planning to do the same with some seeds that I acquired from a local park. this will be my first time for such an experimentation and I could use some help. Can you kindly give some more details about your environment -- like temperature, humidity, how long to keep the light on per day, any special kind of potting soil used etc etc... Thanks...
RedGhost: the set up that I use is in my basement. At this time of year the temps are mid to high 50's and the RH anywhere from 40-55%. I run the light on a timer for 12 hours. I run it from 7pm to 7am since my electricity is cheaper overnight. I do not plan to adjust the length of the light. In the summer I will probably run a fan also to keep temps lower under the light. I have not checked a surface temp when the light is on, but it does produce a fair amount of heat. I will also use dehumdifier because it gets too humid for non plant materials otherwise. My soil hasn't been consistent. Sometimes I use prepackaged soil, sometimes I mix my own with turface, peat, vermiculite and perlite. I don't have fixed ratios. I typically add Osmocote. Seeds are stratified in the fridge and I start checking for root emergence in about 2 months. Those with roots are planted under the grow light. If nothing growing in 90 days they are placed on top of the fridge. I plan on sticking back in fridge again if they aren't germinating in 60 days. I will continue the cold/warm cycle for a while to see what happens. As mentioned on other posts some seeds are harder to get to germinate. I picked some seed off green leaf a.p. at the Albuquerque zoo in November and have had about 50% germinate so far. None of my local seeds have had nearly that percentage. keith
Does anyone know how seedlings would do under a lower watt light? Like the Envirolites - Compact Fluorescent Grow Lamps, they are designed to seedlings and are a much more cost effective 125W. Also they give off very little heat. I am thinking of buying one so I can start seedlings off a little earlier, then I just need to get some seeds... if anyone has any spare ;)
The Envirolites will work. Maples don't need the same intensity as some other trees to do well, and many Japanese ones prefer light shade.
Hi, I am also growing some maple seedlings under lights. I am just using the cheap cool whites from Lowe's. It seems to work okay and I am also leaving them under 24 hour light as I do with other perennial seedlings to encourage rapid growth. I will be placing them in a poly house this spring when I can. Is there any reason I should not do this 24 hour light regiment (other than the cost of electricity)? Also, no one has mentioned whether or not the seedlings need to be under high humidity or not. Right now mine are just sending out their first true leaves and I have them under a plastic tent made from laundry bags. I planned to harden them off in time, but was wondering if they really need the extra humidity or not? Kay Dye
RonB I checked just to make sure and the only herb under the light was Rosemary. A few years ago i was awakened early on a saturday with a guy asking for 'the meth stuff.' I stared blankly and he went away. I took his tag # and called the sherrif. Turns out it was a deputy in plain clothes and unmarked vehicle. Went on down to the neighbors and found what he was after. I think 1000W is overkill, but that is what I had. Not sure what possesed me to get that originally. My orchids all died with I had to put them in 'foster care' for a year and I didn't have the bug when I got home. kaydye, I don't think that there is much advantage to tenting if you are careful in your watering, except when the seeds are shedding their coats. My experience is that they can get stuck when overly dry. I usually cover mine until the seed coat is shed. Keith
Well if the cops got the meth lab or pusher off your street then being awakened by mistake might have been a fair tradeoff. Meth is awful. At least they didn't ransack your house by mistake. Being deciduous the maples will probably need to go dormant and set overwintering buds at some point in order to grow again another year.
Thank you Keith for sharing this. would you be kind enough to also share how the germination process goes. is it the regular -- keep seeds in a moist medium in a ziploc bag (with holes) and refrigerate ? thanks again!
Is this a metal halide light gotten from a farm supply or similar venue for lighting farm yards and parking lots? How big is the light spread? Read chapter three of Botany of Desire for a fun take on why undercover agents might be knocking on the door or someone with high-powered grow lights going all night.
RedGhost: i pretty much follow the standard germination practice from VerTrees. Even with fresh seed I will soak for 48 hours and discard seed floating at 48 hours. I put in fridge in ziplock of moist vermiculite or perlite . I don't put holes in bag, but after about 8 weeks I will check the bags regularly for germination. I try to transplant as soon as root emerges. The topic at the top of this forum 'maple seeds won't sprout' has great info. http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=11439 chuck Metal Halide can be purchased many places. I bought mine online. Spread depends on wattage. See the following link for a diagram of coverage. (you will have to scroll down a bit) http://homeharvest.com/hydrofarmXtraSunValubriteMH.htm I think parking lights are high pressure sodium (HPS) which have a different spectrum. I like the MH spectrum. A little phototherapy when the winter blues set it. The MH are better for vegetative growth and the HPS better for fruiting/flowering keith
