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In picture 1, those very bottom two leaves are the seed leaves. They look different from the main leaves, and are supposed to turn yellow and drop off. Nothing to worry about with those.
In the other pictures, are all the leaves drooping, or just the bigger ones? Are the smaller ones that are growing new in the centre of the plant also droopy?
I would not suggest that you try rinsing off the compost again. Doing this can damage roots in itself.
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I think the pot is too small. They need high humidity and moist soil. They wilt quickly if they need water.
Hey, there is one more thing, i don't know if its ok to post it here or if i should make another topic but i have some cucumbers i grew from seed, the drooping one is one i got from the market because mine are still small and i wanted at least one big one XD, anyway the seed ones are planted outside actually in the ground are doing really well so far. The problem is i didn't expect this many to germinate.
They are quite close together, probably too close and i was wondering what i should do. The 3 options i can think of are.
1. Leave them be and the strongest will survive. My worry with this is what if they all fight over space and end up all dying.
2. Try and transplant some, this is what i would like to do to save as many as. possible although my worry with this is moving some out might not only damage the roots of the one thats being moved but also the ones its near.
3. Cut down the smaller ones so they die and leave the bigger ones that are more spaced out.
Thanks