Return to the Growing from Seed Forum | Post a Follow-Up

 o
Mini-greenhouse for seedlings, upstairs window

Posted by chazman113 Delaware (My Page) on
Wed, Feb 15, 12 at 14:20

This is my first stab at growing plants from seed. I have an upstairs room that would be perfect to grow out my plants as it has a sunny window and my wife won't complain about it taking up space. My concern is it is a little cold. It's generally unused and unheated. It still gets heat seeping up from downstairs and stays in the sixties. My idea was to frame out a little "mini greenhouse" that would trap some more of the sun's heat and I was also going to put a little power compact grow light at the top of it to provide additional heat, light. basically I was going to frame it out with some wood and staple poly to it. Does this sound like a viable idea?


Follow-Up Postings:

 o
RE: Mini-greenhouse for seedlings, upstairs window

Viable, yes. But with some considerations. First, your 60+ degrees is great for growing the plants AFTER they germinate. Temps are only a concern for germination and then it is soil temp, not air temp that is important. After germination air temps are vital and 60-65 is considered the ideal. Much hotter results in leggy growth, stressed plants, and potential fungus problems.

Second, with direct sun on it the enclosed plastic space will "trap" heat and can get way too hot quickly so it will need to be monitored closely and vented/opened as needed. It would be better to provide supplemental lighting rather than the direct sunlight. The spectrum, intensity, and # of hours of exposure are all so low this time of year that about all it provides is heat. Using supplemental fluorescent lighting makes temp control much easier.

Third, using a source of bottom heat on your seedlings assures quicker germination. Light isn't needed to germinate, just soil heat, unless you are growing one of the few flowers that need light.

Dave


 o
RE: Mini-greenhouse for seedlings, upstairs window

  • Posted by t-bird Chicago 5/6 (My Page) on
    Fri, Feb 24, 12 at 9:47

I've had the same scheme in mind, but now I see the need for supplemental light. My area - which is not yet put into play - are corner windows, 2 to the south and 2 to the west on the 2nd floor, which I thought ideal.

My plan included mirrors behind and under the pots to reflect the light from all angle, and I thought would be sufficient - but we've had no real sun at all for 5 days straight, and I realize, that some supplemental would be needed in such a time.


 o
RE: Mini-greenhouse for seedlings, upstairs window

I just started a tray of different veggies. I use a propagation tray 32 coco pots a humidity dome and a hydro farm seedling mat. They're in a closet under a 4x48" t5 flourescent light . It took only a week for all my seeds to pop . Except for habeneros they'll take longer. My seeds include ; better boy, Roma, cherry, and yellow tomatoes, zhuccuni, cucumber, green beans, orange bell peppers, and the habeneros. I like the dome because it traps warmth and the vents allow control over humidity . I've always had success with this method. I think even in a window the light would be sufficient for starting the seeds. The mat produces the needed heat for fast germination and root growth.


 o
RE: Mini-greenhouse for seedlings, upstairs window

Isn't 60-65 a little cool? All my pepper and tomato plants have purPle stems due to cold soil. Any advice?


 o
RE: Mini-greenhouse for seedlings, upstairs window

lay them over on the soil - looks like you have room - and bury all that naked stem under several inches of soil. Just leave the tops above grounds and move your cages over. Water them in well. Give then a week then feed them well.

No because the goal at this stage is root development not top growth. Warmer air temps not only encourages leggy top growth and the development of molds and fungi, but also increases the demands for watering which slows root development. Phosphorus uptake to the stems and leaves is slowed by the cooler temps because it is used by the roots where it is needed.

If you feel the purpling is too severe then your plants may need a mild feeding depending on what growing medium you are using and the size of the containers the plants are in. Young small seedlings in too large a container are more prone to retarded phos uptake and seedlings that are in too small a container so are rootbound will also show signs of poor nutrient uptake. In other words, it is a balancing act so don't just assume it is due to cooler soil temps.

Dave


 o
RE: Mini-greenhouse for seedlings, upstairs window

Isn't 60-65 a little cool? All my pepper and tomato plants have purPle stems due to cold soil. Any advice?

Sorry for the misquote above. This is the question I was addressing.

Dave


 o
RE: Mini-greenhouse for seedlings, upstairs window

Crystal clear. Thanks Dave!


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Growing from Seed Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here