Return to the Growing under Lights Forum | Post a Follow-Up

 o
Help-seedlings have true leaves..Now what??

Posted by connie1946 4 (My Page) on
Sun, Apr 12, 09 at 20:35

I'm confused about the steps needed after my annual flower seeds germinate.
I find different "rules" and suggestions from several websites.
This is what I have done so far: I filled some 3"x3"plastic pots and some little square peat pot strips (Jiffy from Walmart) with moist organic soil-less seed starting mix about 10 days ago. I kept the pots covered with plastic to conserve moisture and set them under florescent lights (about 70 degrees F under the lights...sometimes a bit warmer). After they sprouted I removed the cover and kept the seedlings under the lights. Now most are 2 or more inches tall and are getting their second set of true leaves.
QUESTION: The soil less seed starter mix has no nutrients. The seedlings are growing their 2nd sets of true leaves...but how long can they stay in the soilless mix?
And how long do they have to stay under the lights?
I'm in Door County, WI. and will have 6 or more weeks to go before no frost danger.
Somewhere I read that at his time I should transplant these tiny seedlings with their 2 sets of true leaves into containers of potting soil (or garden soil) and continue to raise them under the lights for the whole 6-8 weeks. Then, after hardening off I'd move them AGAIN into the garden.
Will the plants be strong or even survive if they stay in soil-less mix and under florescent lights that long? I'd like to just start seeds in something that will support them for the whole indoor time.
ALSO...If I start many annuals like this I will eventually run out of room under lights. When the seedlings are 3" or 4" can they be moved to sunny windows and I can keep using the lights for the youngest plants?
**What does anyone think of this idea: mix 3/4 sterilized potting soil and 1/4 soil less seed starting mix,(to loosen the potting soil). Then moisten and use this combination to start seeds? My idea is to provide some nutrients for them while they're still indoors.
So far the only plants that I have under lights are Nasturtiums and Snapdragons. This afternoon I put some Stocks seeds to start so of course they aren't germinated yet. I'd like to start several more varieties of annuals and will appreciate any advice.
Happy Easter.


Follow-Up Postings:

 o
RE: Help-seedlings have true leaves..Now what??

The seedlings are growing their 2nd sets of true leaves...but how long can they stay in the soilless mix?

When they're young, they basically live off their seed leaves. However, if they're working on their second set of true leaves, they're going to need some nutrients soon. You can start them off with a mild fertilizer solution (preferable) or get them into a richer soil mix..

And how long do they have to stay under the lights?

Until they're hardened off outside, of course ;) I'd avoid transplanting unless you either need to thin out your seedlings or unless they outgrow their pots. Transplanting is generally a shock to plants.

Will the plants be strong or even survive if they stay in soil-less mix and under florescent lights that long?

Plants don't need soil to thrive. That's what hydroponics is ;) The sun is better than pretty much any light setup you'll build, but most plants can survive just fine under fluorescent lights, provided you make sure there's sufficient light.

When the seedlings are 3" or 4" can they be moved to sunny windows and I can keep using the lights for the youngest plants?

It depends on how sunny your windows are. You could consider supplementing them with additional light in their new location, if possible, such as a clip-on spotlight fixture with a bright CFL.


 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 under Lights 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.
  • Please review our Rules of Play before posting.
  • 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