All my seadlings die


Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
ok, sorry if this goes long.

Last summer I built a greenhouse for my 11yr-old girl. She wanted to grow Petunia's and sell them at the farmer's market this summer. I built a greenhouse for her hast summer and we started ordering seeds, pots, and other equipment in December. We planted 150 seeds at the end of January. I bought Burpee Seed starting mix. One thing that puzzled me was, that there was no seed starter mix that identified the ph of the soil on the bag. this seemed like something that should be prominent on the bag and it frustrated me that I had to take a chance on something.

The seeds germinated within a week and a half or so, and before that had all germinated, those that had germinated first started to wilt and die.

I suspected the PH was wrong. I tested the soil, and found it has a ph of about 5, whereas I needed about 6.5 I think. I bought lime and mixed it with water and started watering with the lime water.

the grow lights that I bought seemed odd to me from the start. They had a pinkish-purple light. I suspected that it this might have been part of the problem. Maybe the seeds had the energy within them to germinate, but the light wasn't giving the plants what they needed. I bought a second grow light from another company, which was white, and I left both on. I also thought that the plants may need food, so I started using Miracle-Grow in place of the lime water after a few days.

Finally, the basement was cool, probably about 70degrees, which I originally though should be ok for seedlings. But I brought in a couple heaters just to be safe, and kept the temperature at about 75 degrees. We had plenty of petunia seeds, so we replanted in February - now with new lights, heater, and miracle grow. Same thing happened.

This was agonizing. I have a 12x20 greenhouse waiting for 150 petunias, and only 3 survive, and they're not even an inch tall right now.


I found some vegetable seeds that I thought might do better in the seed starter mix. I thought the vegetables would be more robust, and maybe be better suited to the PH. I planted Peas, Green beans, Cauliflower, and Broccoli. The seeds were several years old, so I thought I might have trouble. Only 2 of 50 peas came up. Most the green beans came up and did very well. The broccoli took a while, but eventually came up, and the cauliflower came up almost 100%. I didn't know what was up with the peas, but I was content to imagine that it was because the seeds were too old.

A few nights ago, I took them into the greenhouse to get natural light. the greenhouse has been about 78 degrees during the day, but I kept them well watered. After the first day, they looked great. I went out the second day, and they had all wilted. They were folded over like the stem couldn't hold the weight of the plant.

I read allot of webpages and watched allot of videos on YouTube to get help and understanding prior to planting anything, and it always looks like the plants do all the work. Nobody said, Petunias are tricky or difficult. As a matte of fact, they're supposed to be pretty easy to grow. The people plant the seeds, then they grow. No magic. No dire warnings. Just advice on how to optimize their growth. I don't get it. I can't even get them to grow let alone optimize. What am I doing wrong?

Any advice is GREATLY appreciated.
 
Ad

Advertisements

Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
You are doing a super job! I learned, that seeds will make adjustments to the pH through adaptation. Water management is the most important thing in the sprout, seedling and veg. stage. Using Tap water can cause problems with nutrient absorption and that's why I only use RO or Rain. With any greenhouse plants you have to use wet dry cycles to make sure the roots get oxygen. If the soil is too wet the roots can't get oxygen and they will fall over. Measure your water and units so you will know how much and when to water. I use this 75 ml turkey baster to water my sprouts and seedlings. Water management is also important because water releases nutrients. You're on the right track.
 

Attachments

  • IMG_1495.JPG
    IMG_1495.JPG
    171.6 KB · Views: 106
Joined
Feb 2, 2014
Messages
9,391
Reaction score
4,373
Location
Tarpley Tx
Hardiness Zone
8b
Country
United States
If I were to hazard a guess I would say that you had damping off disease. If the little plants have a narrowing at soil level on the stem then that is what it is. This narrowing is usually a whiteish color and the diameter of the stem is reduced by about 50%.
 
Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
Damping off typically occurs when old seed is planted in cold, wet soil and is further increased by poor soil drainage. If you have good drainage and good seed with the best water management, Damping Off Disease won't be an issue. If you over water, then yes you can have Damping OFF Disease, or soil fungus pythium. That's why you should measure your water intake or water volume of every plant, if you are having problems with sprouts or seedlings.
 
Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
Having a greenhouse is probably one of the most rewarding things to have in the horticulture world. I love greenhouse growing most of all and miss working there everyday. The growing principles in a greenhouse are different from outdoor horticulture. When you run into a problems in greenhouse growing, you have just missed a basic principle. Every mistake you run into in the greenhouse is a golden opportunity to make an advancement in a growing principle. So don't give up, because there is always an answer to your greenhouse problems just around the corner..
 
Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
Damping off typically occurs when old seed is planted in cold, wet soil and is further increased by poor soil drainage. If you have good drainage and good seed with the best water management, Damping Off Disease won't be an issue. If you over water, then yes you can have Damping OFF Disease, or soil fungus pythium. That's why you should measure your water intake or water volume of every plant, if you are having problems with sprouts or seedlings

I'd like to thank everyone for their responses.

From what I've read here so far, I probably have 2 things going on. The old seed and over-watering probably occurred with the vegetable seeds. The seeds were several years old, and I may have overwatered...I don't know. So let's talk about that. I wouldn't know what amount to measure to... how much should they get? It seems that if a plant needs water, it should always have some. However, someone posted that they need dry time too. So lesson learned. but how do I know how much to give them? I've read allot, not to over-water, but that doesn't mean anything if you don't know what over-watering is. Sometimes they use phrases like, just water till it's damp. but how wet is damp?

Like I said, there's probably another issue going on here too. The Petunias were new seed from Harris Seeds. I used a spray bottle to water them, and gave them about 6 sprays per plant per day. That doesn't seem like too much water....maybe it was.

Should I consider letting the soil dry out before watering each time?

Thanks,
 
Ad

Advertisements

Joined
Feb 2, 2014
Messages
9,391
Reaction score
4,373
Location
Tarpley Tx
Hardiness Zone
8b
Country
United States
I don't know how you water but with my seedlings, I place the container/containers into 2 or so inches of water and let the soil suck up the water until it stands on top or becomes completely saturated. After this happens I remove the containers from the water, let them drain and replace on the heat mat or source of heat. When the soil on the surface becomes completely dry I know that the plant will need water within a day or two. On a small cell container, about 2 days is maximum after the top becomes dry but with larger containers it will be longer. It will depend also on what material the container is made from. Plastic, peat, coir, manure or something else. It also depends on your potting soil as to how long it will retain moisture. It is a fact that cool soil and staying too wet leads to damping off but if your potting mix was not sterile and had the fungus you will contract damping off. I haven't bought potting mix or any growing medium in years. I use my own homemade compost for my seed starts. If I do not sterilize it I will get damping off. Even when I do sterilize the mix I still sprinkle the top of the potting soil with horticultural cornmeal. I haven't lost any type of seedling in years and years to damping off. Damping off will happen whether the containers are on cold concrete or a heat mat if the medium is not sterilized and it has the fungus.
Did you look at the base of the seedlings to see if the stem at soil level had shrunk? If they had not shrunk more than likely the seeds were not top notch.
 
Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
I don't know how you water but with my seedlings, I place the container/containers into 2 or so inches of water and let the soil suck up the water until it stands on top or becomes completely saturated. After this happens I remove the containers from the water, let them drain and replace on the heat mat or source of heat. When the soil on the surface becomes completely dry I know that the plant will need water within a day or two. On a small cell container, about 2 days is maximum after the top becomes dry but with larger containers it will be longer. It will depend also on what material the container is made from. Plastic, peat, coir, manure or something else. It also depends on your potting soil as to how long it will retain moisture. It is a fact that cool soil and staying too wet leads to damping off but if your potting mix was not sterile and had the fungus you will contract damping off. I haven't bought potting mix or any growing medium in years. I use my own homemade compost for my seed starts. If I do not sterilize it I will get damping off. Even when I do sterilize the mix I still sprinkle the top of the potting soil with horticultural cornmeal. I haven't lost any type of seedling in years and years to damping off. Damping off will happen whether the containers are on cold concrete or a heat mat if the medium is not sterilized and it has the fungus.
Did you look at the base of the seedlings to see if the stem at soil level had shrunk? If they had not shrunk more than likely the seeds were not top notch.


I took a few pics of the plants as they were dying. The edges of the leaves curled up and the step sort of wasn't able to support the weight of the plant any longer.
 

Attachments

  • 20200412_170605.jpg
    20200412_170605.jpg
    158.6 KB · Views: 111
  • 20200412_170611.jpg
    20200412_170611.jpg
    151.1 KB · Views: 96
  • 20200412_170616.jpg
    20200412_170616.jpg
    177.1 KB · Views: 90
Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
I took a few pics of the plants as they were dying. The edges of the leaves curled up and the step sort of wasn't able to support the weight of the plant any longer.


Actually, I can do better than those pics. This one shows one that has wilted, right next to one that still loos healthy.
 

Attachments

  • 20200415_234346.jpg
    20200415_234346.jpg
    164.3 KB · Views: 101
Joined
Feb 2, 2014
Messages
9,391
Reaction score
4,373
Location
Tarpley Tx
Hardiness Zone
8b
Country
United States
Actually, I can do better than those pics. This one shows one that has wilted, right next to one that still loos healthy.
It is not damping off disease. It looks more like fertilizer was in the soil what with the curling twisted leaf. I'll admit I am at a loss as to what happened.
 
Last edited:
Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
So sorry you lost your plants. I see this all the time and its a simple mistake of drowning the roots in excess water. It's a common mistake and it happens a lot with people starting seed. Start again and this time use a measuring device and only water after the soil drys well. Sometimes I wait 10 days before watering. I water my small plants lightly with a turkey baster or a 500 ml syringe. I never saturate my little containers with water in the very beginning.
 

Attachments

  • IMG_1502.JPG
    IMG_1502.JPG
    152 KB · Views: 94
  • IMG_1503.JPG
    IMG_1503.JPG
    154.2 KB · Views: 112
  • IMG_1504.JPG
    IMG_1504.JPG
    115.7 KB · Views: 117
Ad

Advertisements

Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
Well, I've heard it now from several of you....I drowned my plants.

I never knew that he soil had to dry out between waterings. I assumed that the soil should stay damp.

I don't want the greenhouse to be a complete waste this summer, so I ordered Marigold seeds for my girl to plant. Maybe she can pot them and sell a few this summer. She doesn't need to make a bunch of money. I just want her to feel like she's acccomplished something.

If there are any suggestions regarding marigolds, I'm all ears!

Thanks
 
Joined
Feb 2, 2014
Messages
9,391
Reaction score
4,373
Location
Tarpley Tx
Hardiness Zone
8b
Country
United States
Think of it this way. Does it rain every other day? Does Mother Nature keep the soil wet? There is a big difference between moist and wet just as there is between damp and dry. I don't think any of us is saying to let the soil become completely dry, void of all moisture from top to bottom, but dry enough to let oxygen down into the roots. Excess water stops oxygen and that means death sooner or later to everything that does not actually live in the water.
 
Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
Every mistake is a golden opportunity to advance in Horticulture. Don't look at mistakes as failures because they are not failures. A lot of the horticulture skills I developed, came from past mistakes. I have killed my share of plants over the past years too. Time to replant with your watering new skill.
 
Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
Thanks for the help everyone.
As soon as the marigold seed comes in I'll be trying again. I'll be sterilizing the soil and using a new watering regiment.
 
Joined
Feb 21, 2020
Messages
871
Reaction score
247
Country
United States
Rooster here's one i just killed last week! I had a succulent that flowered and I waited until the flowers were dry on the plant, and I snipped it and watered her well. Big Mistake I killed it by over-watering. I managed to get a pup and a bunch of seeds out of her, but she a goner now. I felt bad but, I won't do that again, so maybe it was worth it to learn. Here she is and her pup too, her pup is very happy.
 

Attachments

  • IMG_1511.JPG
    IMG_1511.JPG
    163.6 KB · Views: 98
  • IMG_1512.JPG
    IMG_1512.JPG
    104.8 KB · Views: 116
Ad

Advertisements

Joined
Apr 12, 2020
Messages
14
Reaction score
11
Country
United States
Rooster here's one i just killed last week! I had a succulent that flowered and I waited until the flowers were dry on the plant, and I snipped it and watered her well. Big Mistake I killed it by over-watering. I managed to get a pup and a bunch of seeds out of her, but she a goner now. I felt bad but, I won't do that again, so maybe it was worth it to learn. Here she is and her pup too, her pup is very happy.

Thanks for the support. I'll be trying again as soon as the seed comes in the mail.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top