Greenhouse Seedling Troubles

Hi Everyone,

I am not sure if this is the correct forum to post this question but here goes.

For the past 3 years I have started my tomato, herbs and other veggies in coldframes and had great success. This year my wonderful husband built me an 8x12 greenhouse and I have gotten stuff to germinate, veggies, flowers even peppers and eggplant. I started them in "peat pots" that I bought at Lowes. Problem is after germinating and getting one set of leaves, they wont do anything? They are all staying small and that is it. I am keeping them really wet, good heat, circulating air, used seed starting soil that I used in my cold frames.

I am so confused and frustrated. The flowers are doing the same thing? I checked the roots and all have a good root system. I even transplanted into a bit bigger peat pots thinking they needed more space, but nothing. The only thing that grew bigger was my cukes but they turned yellow so I put them in the garden hoping to keep them going. If we don't get a frost they should make it, they were and early variety.

PLEASE! Any thoughts on what I am doing wrong? My tomatos got huge in my cold frame, I am not understanding why they are not doing as well?

Thanks,
Susan in NC

Susan-one thing that caught my eye is that you said that you were keeping them really wet. As a rule, I would not advocate doing that. Roots grow much better in dryer soil as there is more oxygen (water displaces oxygen) and plants need roots to generate leaves and vice versa. That said, I know nothing about growing in peat pots. I grow in a soiless mix that has good drainage, and that I think, from what I have heard, you get better control of the drainage situation with the soiless mix versus peat pots. Its also better to water in the am and let the soil dry some during the day so that the soil has more oxygen at night as that is when the roots grow the most.
Just reread your post-what about fert and the daytime temps? Are you fertilizing and is the grhouse too hot during the day? What are the night time temps?

Hi Lily,

Whhhaaaaaaaaa! :(

Based on your questions, I CAN'T DO THIS! It is too hard!

Ok, I was told by a neighbor that has a greenhouse (and her stuff is all huge) that my stuff was too dry, so I started keeping it wetter. Day time temps range between 80 to a highest of 107 one day. When it gets real hot I crack the window and turn on a fan I also have a temp controlled vent that works great.

I use a seed starter bagged soil because that is what I used in my coldframes and it was wonderful. The soil has fert in it so I did not add any, I have read that too much fert on seedlings can harm them? I will say that I have researched and read up on this stuff and there is so much conflicting info out there it is ridiculous! It is very frustrating. I am ready to go back to using my coldframes for the tomatoes if things don't get better soon. My neighbor seems to think it is the peat pots. She fills a tray with soil and broadcasts then transplants.

I hate when I can't figure out a problem and solve it.

???????????????

Thanks for trying to help,
Susan

Your temperatures are probably contributing to the problem--80 is probably OK but if you're getting much warmer than that the seedlings won't be happy and won't grow well. I know you said you had a temp controlled vent but if it's letting things get up to 107 then you should see if you can adjust things or put in some additional fans/vents.

susan, I would say that its better to always keep the soil on the dry side then wet side. When your friend said that your soil was too dry-were the plants wilting? You would be surprised at how well seedlings do in dryer soil. People see the dry soil and panick and want to reach for the hose. It took me a few years to relax and let the soil stay on the dry side. Alot of times, if the plant is starting to wilt and its late afternoon ( no sun shining on it) I will let it go and wait to water the next am. That said, it is possible to stunt plants by lack of water. Its really hard to tell without seeing your operation. If you let the soil dry out between waterings is a safe way to go.

Concerning fert in the soil-there is basically nothing there. I transplant small seedlings in soiless mix that has a starter fert in it and start fertilizing right away. I think I would start fert with a weak solution once a week if I were you.

Maybe you can show us pictures of the plants that are not growing. I feel like I am telling you to do stuff and I really don't even know how big these plants are! It may be the peat pots. I grow like your neighbor does.

ARGGGHHHHH!

Lily I appreciate your info and patience with me. Could be it has been getting too hot , I will run the fan moire often, I admit I thought hot was better. Also, I will start fertilizing them a little each week. I also will let them dry out more. I have to say though since I went the more water way things have been germ'ing faster which is good.

Now you got me thinking, when I used the cold frames I didn't keep them as wet, they did dry out well.

I guess this greenhouse stuff is tricky and needs to be mastered.

I will try and post pics this week I ordered a new digital camera and should be getting it any day now.

Thank you,
Susan

Warm is good, hot is not. I think I read somewhere that above 85 degrees some of the plant's functions start to shut down and they don't grow as much or something along those lines. And I know the AHS uses days above 85 degrees as their metric for figuring out which heat zone you're in, and if you have too many days over 85 it starts to limit some of the plants you can grow. So I think keeping it under 85 is probably your best bet.

Ecrane is right-85 is ok. If you can, try to keep the difference between the nighttime and daytime temps around 15 degrees if you can. For example, the thermostats on my heaters are set at 60 and the fans during the day are at 75.

Regarding watering-I thought we were talking about after the seeds had germinated and had their true leaves. Its a whole other ballpark for watering when germinating!

We are here to help-both ecrane and I love to pass on our knowledge, although ecrane is more patient and probably a better typer than I ! Most people are, although I will say (quite proudly :) ) that I can sort of type without looking lol

I am having pretty good success with germinating it is after they get their first set of leaves that things seem to move very slowly and very SMALL-ly.

Here is a pic of the tomatoes.

I would give that a shot of weak solution fert once a week and full sun in the grhouse. Give us an update in a week! By weak solution, I think it would be a 1/4 of a T of liquid fert per gallon of water and water it until it reaches the bottom of the pot. I think full strength is a T/gallon of water-but maybe someone else that fertilizes by the gallon can say better. I do much larger rates, so I am not sure.

Ok, I will let them dry out a bit and start fertilizing.

Thanks,
Susan

Thanks for the tip on over-watering. I'm only on day 3 with my GH and I think I've been doing just that. I'm going to cut back on the water and up the fert a tad and see if it doesn't make everybody a little happier.

Susan,
Tigerlilly is rightr about letting the plants dry out. Seedlings don't like wet feet. Give them air circulation and start fertilizing like Tiger said. I am growing under grow lights and also moving them to mini greenhouses. I keep them about 60 at night to 75 during the day. Try using a little kelp about once a week. Kelp enhances nutrient uptake and maintains top performance. It especially benefits plants during drought and other periods of stress. I spray once the first true leaves devlope.

"Stay Happy and Keep Gardening!"