Temperature Controlled Thermostat Set-Up

[bobbywett]

Hello Folks,

I just ordered 12 Pine Seedlings and 12 Hinoki Cypress seedlings and their shipping out on Monday. The roots are amazingly developed on these seedlings and I want to protect them as much as possible given my location 6B. I have an un-heated, detached garage in which they will spending the winter. I am going to build a makeshift greenhouse of sorts. I’ll be building a small wood frame and placing it on a patio table/stand with a steel grated top. I’m going to cover the frame with greenhouse plastic and I’m going to heat it with the 2-stage digital temperature controller in the link below.

My questions are:

1.) Should I use a lightbulb set-up as the heat source? If so what bulb would you guys recommend? Should I use some sort of heater instead of a lightbulb?

2.) What temperature range would you folks recommend I set for a start/stop

3.) What do you guys think about my plan ... any suggestions would be greatly appreciated.


Thanks,

Bobby

https://www.amazon.com/gp/aw/d/B01HXM5UAC/ref=ox_sc_act_image_1?smid=A1RUFFFCQ74BCW&psc=1

 

[BuckeyeOne]

You would be better off with propagation heat mats.
You could still use the controller or look at mats with controllers.
Amazon.com : VIVOSUN Durable Waterproof Seedling Heat Mat Warm Hydroponic Heating Pad 10" x 20.75" MET Standard : Garden & Outdoor

Lights are not needed unless you are trying to push foliar growth. Now might be a little soon for that. They need dormancy, even if they are seedlings.

I would keep them at no more than 40-45F. bottom temp.

 

[Wires_Guy_wires]

1) no.
2) outdoor temperatures.
3) I think your plan can be detrimental to their health. Where are these seedlings coming from? If they come from a local source, I would just keep them outdoors after arrival. It's what I have been doing for the past couple years and it works just fine. I got some itoigawa from Portugal in december, and they're outdoors in the freezing wind.

An outdoor frame with plastic can become a wind catcher.

 

[bobbywett]

1) no.
2) outdoor temperatures.
3) I think your plan can be detrimental to their health. Where are these seedlings coming from? If they come from a local source, I would just keep them outdoors after arrival. It's what I have been doing for the past couple years and it works just fine. I got some itoigawa from Portugal in december, and they're outdoors in the freezing wind.

An outdoor frame with plastic can become a wind catcher.

Their coming from CT, but I believe they were germinated in a greenhouse with soil temperature in the 50 degrees F range

 

[bobbywett]

Their coming from CT, but I believe they were germinated in a greenhouse with soil temperature in the 50 degrees F range

 

[bobbywett]

I decided to just go ahead and purchase a shelving unit instead of building one. It‘s on casters so I can wheel it towards the garage door and let the seedlings get some sunlight and air circulation during the warmer winter days. The plastic is 6 mm for the days when the temperature dips into the single digit.

 

[MaciekA]

You're planning to warm up the soil and keep them in an enclosed rack space, but you don't mention your lighting setup, and you don't want to mix warm conditions with darkness. If you seek continuity for your seedlings relative to the grower's setup, then you need to be fixated on light as a first order of business before worrying about root temps. On a rack setup like yours with insulation around it, lights will provide a decent amount of heat on their own. Continuity will require need some properly serious lights. If this doesn't sound fun or achievable, then follow others advice and put em outside, insulated, and accept the risk hit of acquiring non-winterized conifer seedlings in the winter.

If you want to advance the clock to spring time / summer, go full bore and do that. If you want them to avoid burning through stored sugars until spring, then don't limit light at all, and focus solely on preventing the roots from going below 32F and also preventing the whole plant from going above the low 40s.

Choose one of these options

- Cold with darkness (shed/garage). Must not go above ~45F.
- Cold but insulated and outside (either full sun or in a hoop house / greenhouse which is not allowed to heat up significantly).
- Warm and toasty with bottom heating, but blasted with light either with direct sun or proper grow lights (proper here meaning not a $30 amazon fake "1000W" light or an IKEA grow bulb / etc).
- Cold and outside but on heating mats set to prevent freezing at the roots

If I was in your climate and had just acquired conifer seedlings that I knew hadn't gone through the autumn dormancy cascade I'd shove them in my grow tent and let em' rip.

 

[sorce]

Pics!

It all sounds a bit overboard.

Sorce

 

[bobbywett]

You're planning to warm up the soil and keep them in an enclosed rack space, but you don't mention your lighting setup, and you don't want to mix warm conditions with darkness. If you seek continuity for your seedlings relative to the grower's setup, then you need to be fixated on light as a first order of business before worrying about root temps. On a rack setup like yours with insulation around it, lights will provide a decent amount of heat on their own. Continuity will require need some properly serious lights. If this doesn't sound fun or achievable, then follow others advice and put em outside, insulated, and accept the risk hit of acquiring non-winterized conifer seedlings in the winter.

If you want to advance the clock to spring time / summer, go full bore and do that. If you want them to avoid burning through stored sugars until spring, then don't limit light at all, and focus solely on preventing the roots from going below 32F and also preventing the whole plant from going above the low 40s.

Choose one of these options

- Cold with darkness (shed/garage). Must not go above ~45F.
- Cold but insulated and outside (either full sun or in a hoop house / greenhouse which is not allowed to heat up significantly).
- Warm and toasty with bottom heating, but blasted with light either with direct sun or proper grow lights (proper here meaning not a $30 amazon fake "1000W" light or an IKEA grow bulb / etc).
- Cold and outside but on heating mats set to prevent freezing at the roots

If I was in your climate and had just acquired conifer seedlings that I knew hadn't gone through the autumn dormancy cascade I'd shove them in my grow tent and let em' rip.

It looks as if I’ve got some serious decisions to make. Thank you for the in-depth reply