Lettuce Seedlings Browning

Mon Mar 14, 2011 10:53 pm

Hello all,

A week ago I started some lettuce, I did it in ziplock bags as that has always worked well for me. Once it sprouted, I transplanted it into my Grodan starter cubes, they were presoake in 1/4 strength 5.5 pH balanced water per the Grodan specialist.

I then placed the cubes in a mini greenhouse (aka a clear plastic contained that traps humidity) to allow the seedlings to root in some, etc. I have no watered them, the Grodan cubes are not dry. They get about 6 hours of natural sunlight a day. One is looking good the other one is not, it looks grim and is browning and wilting a little. The other never sprouted leaves, just turned brown and wilted.

I have some pics below. Does anybody know what might cause this? Thank you....

Lettuce Container

http://s4.postimage.org/xkypffixe/lettucecont.jpg

Overview of Plants

http://s1.postimage.org/9y8azzas5/plantoverview.jpg

Healthy Plant?

http://s1.postimage.org/9y8fylc9h/healthyplant.jpg

Not healthy plant?

http://s1.postimage.org/9y8o8a2qd/dyingplant.jpg

Mon Mar 14, 2011 11:25 pm

First thing, I believe what you are calling a healthy plant, is not a lettuce, but a brassica of some kind.

I think the unhealthy one maybe lettuce, but can't tell for sure. I believe the dome is your problem. The lettuce? is probably over heated and high humidity.

Eric

Mon Mar 14, 2011 11:30 pm

Hehe, but... the seeds I used were all lettuce seeds and I was working in a clean environment, I can't imagine it'd be anything else. It is a unusual leafy central american lettuce, it may be different from what you are used to....

Or maybe somehow something else got mixed into my seed pack?

Also, you suggest I lift the dome? I have the dome because I was told it was good for the humidity... but would I be okay if I lift it then?

Mon Mar 14, 2011 11:46 pm

I don't use domes, but what I keep hearing is to remove the dome as soon as they sprout. Others have said to at least prop open for a little ventilation.

It is a unusual leafy Central American lettuce, it may be different from what you are used to....

do you have the variety name?

Eric

Tue Mar 15, 2011 1:17 am

I have opened the dome.

The variety is:

Simpson

Tue Mar 15, 2011 3:29 am

Well I will say it again, I don't think the healthy one is Simpson, a very popular black seed lettuce.

Eric

Tue Mar 15, 2011 6:24 am

i do not dispute your knowledge as you have far more experience than me. They both come from identical black seeds in a sealed package for simpson lettuce. It would be crazy if its not lettuce...

Guess time will tell?

Tue Mar 15, 2011 11:51 am

DDF is right, those bi-lobed cotyledons are quite distinctive for brassicas -- could be broccoli, cabbage, cauliflower, they all look pretty identical at that stage. Baby lettuce has single lobed cotyledons (seed leaves) like this:

http://kelbycarr.com/sustainable-kitchen-project/

It isn't as uncommon as you would think to get mislabelled seeds, even from reputable companies. The thyme I planted last year all turned out to be some kind of mint. I was quite disappointed.

Then this year my lavender was mostly lavender but one of them was some kind of weed that looked similar in the beginning but had a much more branching form and no lavender smell.

Fri Mar 18, 2011 9:13 pm

Thanks for the info! I went ahead and planted some more lettuce seeds, maybe just that one was a fluke.

They got very leggy so I am guessing they were planted too deep.

I dropped the dome, added water + nutrients and the new ones I have outside of a dome and planted on the surface of grodan cubes. From what I hear lettuce does fine on surface and isn't a big fan of beeing deep.

Fri Mar 18, 2011 10:59 pm

They got very leggy so I am guessing they were planted too deep.

Better lighting. :wink:

Eric

Fri Mar 18, 2011 11:27 pm

Thanks DoubleDogFarm. Any suggestions for what lightning that is cost effective I can get at a hardware store? Would normal energy saving bulbs work at close range?

I live in C.A. and electricity costs 3x what it costs in the USA so we have to be careful.

Sat Mar 19, 2011 12:04 am

hydrolifeCA,

First, please call me Eric.

I would go for something like this. Hang them from chains so you can raise as the plants grow taller. http://www.acehardware.com/product/inde ... 02.1259174
They need to start just a few inches above the soil when starting.

I believe it was hendi_alex that said compact fluorescents ( CFL) would work for about 1 square foot per light. If you are good at wiring then several of these screwed to a board would work. http://www.1st-product.com/products/624 ... 03687.html

Save some money and buy used, if available

Eric

Sat Mar 19, 2011 1:21 am

Erik great thank you. I'm Luis.

CFL's are great for energy saving and I can wire those up with insulated wire and maybe a PVC configuration. I am not sure. I may just get the other ones and put them on chains.

My system is only six plants so it doesnt encompass much space.

Excellent information!

Sat Mar 19, 2011 12:56 pm

Yes, I use ones like this

http://electrical.hardwarestore.com/13- ... ights.aspx

that come with hanging chains. You can buy them at any hardware or big box store cheap. They work fine, just as Eric said be sure they are just a few inches above the soil, hung so you can raise them as the plants grow.

If you browse around this section you will find pictures of people's seed starting set ups. Once you have some lights, you might decide to plant a few more seeds!