Winter uninsulated garage grow - bad idea?

[BobStrauss]

Have been considering purchase of a 3000w AGLEX grow light to get active growth out of plants in winter - young palms and palm seedlings, as well as potted plants I usually keep on my front and back porches (plumeria, cacti, croton, etc). However, the only good spot for me to do this would be in my uninsulated garage in San Antonio, which has the following average temps by month (high/low):

October 81/58

November 72/49

December 64/40

January 64/40

February 67/43

March 74/50

I typically leave all my stuff outdoors over the winter, bringing the tender plants into the garage when freezes are expected. Usually it stays about 9 degrees or so warmer in there on cold nights.

Question is: in a cool environment where the average lows may be upper 40s, will I get any benefit from the lights? Would the plants and palms still go dormant or growth stall out anyway due to the temperatures?

 

 

[oasis371]

I overwinter my cycads, many palms and citrus in my garage, but only to keep them alive, and I don't expect growth. I do see growth on the Citrus by February but my garage (which is colder than yours) does get full, unobstructed ,southern sun, all day, in Winter.  What particular species of plants are we talking about? You mentioned crotons but those need tropical heat to do anything and plumeria tend to go dormant in the winter anyway. Most palms will also want tropical heat to grow but some like Trachys will grow.  Do you have a basement in the house?

[BobStrauss]

Unfortunately no basement, and I’m very limited with regard to indoor space. Perhaps I could build out a grow room with plywood and reflective film and add a thermostat-controlled heater? 
 

Would be nice to get another 6 months of growth out of my tropicals if somehow possible. As far as palm seedlings, planning on growing Phoenix varieties, Med fan, Robusta hybrids, trachy, Butias - the ones that can survive in my area once established.

[oasis371]

I use oil-filled, electric radiators as a heating source.  I can run one or two or none, depending on the outdoor temps.  This Fall has been very mild my cycads and Butias are sill outside. Is your garage attached or detached, btw.  It does matter. Attached are warmer than attached.  It also matters how many plants you put into the garage!  The more plants, the warmer it gets, interesting thermodynamic here and another excuse to be a palm/plant hoarder. 

My garage is detached and I use a remote thermometer probe that monitors temperatures and records temps on a 24 and 48 hour schedule, maximums, minimums and also all time high and minimums. Purchased at Home Depot for $20 and I LOVE it! I think you should invest in thermometer like this to record what is actually going on in your garage

 

Phoenix palms are not so fast in growth, neither are Med fans even in mid Summer. Robusta and filibusta as you know, are relatively fast.  Trachys are moderate but being such a temperate species, not sure if they have a hard wired tendency to slow down in winter anyway. Butias are my fastest growers, can't imagine dealing with them growing all year long. 

 

 

Edited December 13, 2021 by oasis371

[Allen]

You can run the light at night which will act as a heater to some degree as well

[Merlyn]

3000W is a lot of power, though the AGLEX says it consumes 655W total.  I'm not sure how much of that is radiated as heat vs as light.  Consider that a typical "aux heat" electric heating coil in a heat pump furnace is a 5kW or 10kW, and that is enough to heat up an entire house pretty fast.  An efficient mini-split heat pump may consume about 1000-1400W while producing 1 ton (12,000BTU/hr) of heat.  So depending on the efficiency of the grow light, that might be enough heat to warm up your garage by at least a few degrees.  Adding insulation would help, of course.

[climate change virginia]

this is what i did with my plants in my garage this was about a year and a half ago i didnt have time this year to set up the full thing this year because high school ect

 

Edited January 30, 2022 by climate change virginia