Return to the Heirloom Plants & Gardens Forum | Post a Follow-Up

tomato seedling problems

Posted by dkmc (My Page) on
Sun, Mar 23, 08 at 19:18

I am currently growing two types of heirloom varieties; both from Baker Creek, Old Italian and Fox Cherry. I started the Old Italian first and then a week later I started the Fox cherry. Right now, since weather is still a little unpredictable, I have the seedlings in the garage under a couple of aquarium plant lights. About a week ago, I started to notice that my Old Italian seedlings were looking sickly. The cotyledons on most of the plants look twisted and contorted and a few of them have had one or more of the cotyledons shrivel and die. I have followed the same schedule with both varieties, applying fish emulsion once a week, watering with spray bottle etc. A few of the Old Italian plants are showing the first signs of true leaves. Am I dealing with a disease, or just the consequence of being a newbie to the whole heirloom and "start from seed" world of gardening?

Follow-Up Postings:

RE: tomato seedling problems

My guess would be either the fish emulsion or it's just too cold for them out in the garage. I have over 200 tomato plants growing with several being from last year's and the year's before seeds from Baker Creek, including their Fox Cherry. I started mine inside the house (in the family room on card tables where the room temp is 69-70) on top of heating pads and under grow lights and have since had to transplant them twice as they have grown so big. Most are now out in the hoop house, although I've got heat lamps on tonight as it's supposed to get below freezing. You also have to be careful to make sure you don't over water, as that will kill them quick. From the day the seed is planted until the plant goes into the ground outside I only water from below (never the top) in order to encourage roots to reach down. As long as it's in a container, I water from below. Rain water is best, but plain tap water will do. No fish, tea, or any thing else added to the water. Oh and on the lights, it's best if the tops of the seedlings stay about 4 inches from the light, adjusting the height of the light as needed as the plants grow. Hope this helps...

RE: tomato seedling problems

Thanks for the advice and direction. I will check out the FAQ in seed starting. I can start watering from the bottom. One last question: In your experience, how often do you water the seedlings before the first few leaves?

RE: tomato seedling problems

I agree with Regencylass. Your seedlings are probably not getting enough light. You need them under your grow lights for at least 12 hours a day. I am starting over 100 heirloom tomato and pepper seeds under lights now. My tomato stems I think are too skinny and spindly. I transplanted many of them into larger peat pots today and put them back under the light. Does anyone one at what point/size I can plant them outdoors? I live in South Georgia in Thomasville. Never heard of Baker Creek, but I'll look them up.

RE: tomato seedling problems

Start tomato seeds 6-8 weeks before the expected outside planting date; you will have to check with your Cooperative Extension office for that date in your area.

Since tomatoes are warm season plants in order to start them youll need an indoor set up or greenhouse with heat mats. I start mine indoors on a 5 shelf metal metro rack purchased at Lowes. Each 4 foot shelf is equipped with 2, 4 foot shop light fixtures equipped with full spectrum daylight or 2 warm & 2 cool spectrum 4 foot T-12 bulbs, and 2, 2 flat seedling heat mats equipped with thermostats plugged into a power strip.

Nowwhen starting seeds I plant them in community pots or individual cell packs filled with moistened seed starting mix (prepackaged, sterile, without fertilizer). After the seeds (2 per cell or inch apart in community pots) are planted inch deep and lightly pressing them in to maintain good soil to seed contact, I cover them then a dusting of fine vermiculite and mist the cells to ensure enough moisture is present to carry them through germination. The last step is covering the cell packs or community pots (with a clear plastic bag or flat cover) to retain moisture and heat. The heat mat is set at 75 degrees and the lights are set 3 inches above the trays and turned on 14 hours per day.

The cover is removed as soon as most of the seeds have germinated now light becomes the most important factor. If moisture is needed the flats/cell packs/community pots are set in 1 inch of warm water in other words, watered from the bottom. You can tell when the surface of the soil changes color or glistens that water has been absorbed. Take out of the water and drain before placing back on the shelf under the lights.

I have a very small fan that I turn on low for about an hour daily and set a distance that will produce a slight breeze flowing across the seedlings to prevent damping off and to strengthen cell structure of the stems.

Reduce bottom heat to 65 degrees and start fertilizing when the first set of true leaves appears strength of a balanced (N-P-K are same numbers) liquid fertilizer. Transplant seedlings when 2nd set of true leaves appear, remove cotyledons and transplant to just below the first set of tree leaves this allows the plant to set roots all along the buried stem. I use large Styrofoam coffee cups with 4 holes poked in the bottom. After about 10-14 days I transplant them to the garden. Cage and wrap them with a light weight floating row cover that will protect them until they get over transplant shock.


Check flats/cell packs/community pots TWICE DAILY those seeds can germinate in half the time under bottom heat and will stretch beyond saving if you forget to check them.

Use a fresh quality sterile media once opened pathogens can invade store leftover media in a heavy zip-lock bag for future use.

Use fresh seed and dont plant too deeply; check with Cooperative Extension office for recommended varieties.

If you have water quality problems, use bottled mineral water to moisten media and water seedlings.

Fertilizer isnt needed until the seedlings have a root system and true leaves; use a very mild liquid fertilizer (fish emulsion or liquid plant food) strength when true leaves are fully expanded.

Keep lights 2" above seedlings as they grow taller.

If seedlings appear overall pale or leaves loose color its an indication they need nitrogen fertilizer.

Now its time to harden off transplants over a 10 day period before planting in the garden; move them into ever increasing sunlight during the 10 day period.

Keep a journal with varieties, media used, planted how, using what, results, problems, etc; its just as important to find out what doesn't work as what does - experience is the best teacher, don't get discouraged, keep trying!

TJ in Zone 8b Texas

RE: tomato seedling problems

Wow TJ! What a treasure trove of information you have there! Thank you so much for taking the time to share all of that.

RE: tomato seedling problems

When starting seeds, the plants have enough nutrients to survive in seed trays until they need to be transplanted so the use of any fertilizer is not necessary for at least 6 weeks. Remember that organic soils are rich in nutrients and if watered properly they wont be flushed from the soil, I usually wont fertilize until the plants show signs.

I have also noticed that some plants that were purchased from Rutgers University that were placed in my greenhouse are starting to show signs of stress as they are 4-5 weeks old, I believe this is because they received additional artificial light. Plus the weather here in New Jersey has dropped 30 degrees in the last 3 days as we were getting 70+ days right after a severe snowstorm. One day it was winter and the next day it was spring.

 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 Heirloom Plants & Gardens 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