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

Tomato seedlings dying

Posted by farmingvillefarmer East Coast zone 7 ( on
Sun, Apr 1, 12 at 8:54

I'm having a major problem here. Just about all of my tomato seedlings that have germinated die right after their seedling leafs form. The room is about 70 degrees all the time and I make sure they have plenty of water. I started them all in jiffy7 peat pelets in the watering trays that hold up to 38 plants to start. There are four of these trays per shelf with three sets of florecent bulbs totaling six bulbs per shelf. I've done it this way for the last four years without ever a problem. Also dying are my Zinnias and marigolds. My eggplants and peppers so far seem ok. Some people say I may have over watered as the jiffy pelets are soaked to the point where if you take them out water will drip from them. Please help thank you

Follow-Up Postings:

RE: Tomato seedlings dying

Over-watering sounds like it may well be the problem, the roots need oxygen. When the soil is over-watered, the empty spaces (that contain oxygen) are filled with water and the oxygen is forced from the soil. Plant cells required oxygen for metabolism. More plants are killed by over-watering than under-watering.

See if you can set the jiffy pellets on paper towels to absorb some of the water, and let them dry out a bit. You want them to be moist, not wet.

Hope this helps,


RE: Tomato seedlings dying

Thx very much, everything is drying out now, unfortunately I have to buy new seeds and start over

RE: Tomato seedlings dying

Our weather is still to iffy here in Medford so you have plenty of time for new seedlings.

RE: Tomato seedlings dying

I hate to say it, but you are killing them with kindness.

Over-watering tomatoes causes a fungal disease named phytothora to grow rampantly in the soil mix. Tomato seedlings are EXTREMELY susceptible to phytothora. The correct way to manage this problem is to underwater the seedlings. Let the soil dry out to the point the seedlings start to wilt. Then and only then, water them well and let them grow until they dry out again. You have to repeat this cycle of letting the plants grow for a few days and then dry out until the seedlings are ready to set out in the garden.

Once the soil mix is contaminated, it is impossible to grow seedlings in it. Please be sure to toss the soil mix you started the seed in and use fresh sterile seed start mix such as promix BX, Fafard, sunshine mix, or miracle grow seed start mix.


RE: Tomato seedlings dying

I have same problem and The room is about 55-60 degrees all the time but tomato did not grow proper way. I thought that I will try again and buy new seeds. Hope anyone can give me idea.

RE: Tomato seedlings dying

this year, my tomatoes were not doing as well as any previous year. I had changed soil companies, so I changed back. found that I needed to add more fertilizer. But this year has done wonderful for peppers, which normally don't.

 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