Cucumber seedling leaves drying/spotted

[purplegardener]

One more question: I started some new cucumber seedlings inside after the ones outside got scorched in the sun. A few days ago I noticed some weird spots on the sprout leaves and now I see it spreading to the leaves. Theyve never been outside. Theyve been carefully grown under grow lights. (They are all close in the photos, but only so you can see them all at once- they are not normally on top of each other like that)

There are no bugs that I can see. I havent sprayed them with anything.

Any ideas?

[imafan26]

It looks like a fungal disease. It is worrisome that it has appeared so early. Either too much water and humidity or bad seeds. Fungal diseases usually are difficult to stop once they start, even picking off the leaf doesn't always control them. Right now the new leaves look ok, you can try picking off the infected leaves, but if the disease starts to progress to the new leaves, it may be too late.

Getting disease free seeds are important.

Do not reuse pots, soil, equipment from plants that have died in the past and sanitize the area between planting to limit transmission of diseases. I sanitize pots and labels by washing off the dirt and roots and soaking in Physan or bleach for a week. Metal hangers can be sterilized with a torch.

I do grow cucumbers in community pots and I don't have trouble transplanting them, but if the weather permits they are best planted directly in the soil. They should not sunburn if they are started outdoors.

[purplegardener]

The ones outside were also started inside, I moved them outside after some hardening off, but then we had a CRAZY couple of sun/heat days and some of the leaves turned white. A few made it and the new leaves seem to be growing fine, but the others didnt.

I got the seeds from southern exposure- I thought I was getting them from somewhere reputable?

Some of the big leaves are already showing signs of whatever it is. I suppose I should toss them