Yellow leaves on cucumbers, please help

[Comptine]

I'm trying to figure out what I'm doing wrong here. My guess would be either nute deficiency or overwatering. I was hoping to get a second opinion on what's going on. So far it's only 3-4 plants displaying these symptoms our of 25 ish.  
 

 

[JoynersHotPeppers]

First two untrue leaves no biggie, look too wet and perhaps lack of nutrients. Also look like they got watered while sun was on them or sun hit them shortly after.

 

[Comptine]

First two untrue leaves no biggie, look too wet and perhaps lack of nutrients. Also look like they got watered while sun was on them or sun hit them shortly after.

 
They are wet looking right now because I've watered them and transplanted some, and the sun is not on them, they mostly get sun up until 15 o'clock ish. I may have watered them previously whilst the sun has been on, but these guys are in a conservatory at the moment, so it's not full on sun. 
 
I'm just a bit worried and want to catch the problem early if there is one. 

 

[hottoddy]

The lower leaves on my cucumbers often turn yellow and fall off or atrophy, just like peppers. I think it's just a little bit of "out with the old, in with the new." I think it's fine as long the yellowing is limited to the bottom leaves, and the newer ones near the top look fine. Just keep an eye on it.

 

[Comptine]

 I think it's fine as long the yellowing is limited to the bottom leaves, and the newer ones near the top look fine. Just keep an eye on it.

 
Cheers, that's reassuring. First time growing any fruit or veg for me, and I'm completely in charge of the grow, so my plants get a lot of attention and babying (I know I should just leave them to do their thing, but it's hard)

 

[compmodder26]

I'd say if you continue to notice a trend of the lower leaves yellowing, then you probably have a nitrogen deficiency.   Nitrogen is a mobile nutrient, meaning that if there is not enough present in the soil.  The plant will draw it out of the older leaves to help make the new ones.

 

[AJ Drew]

Assuming they are about to go into the ground.  At that point, everything is going to change so thinking that at this point there isn't much that speculation will help with.  One thing though, from experience with cucumbers, zucchini, and other vines in a container grow have learned that when the vine bends over and touches the lip of a container there can be a pinching effect that can royally screw the plant.

 

[Comptine]

Assuming they are about to go into the ground.  At that point, everything is going to change so thinking that at this point there isn't much that speculation will help with.  One thing though, from experience with cucumbers, zucchini, and other vines in a container grow have learned that when the vine bends over and touches the lip of a container there can be a pinching effect that can royally screw the plant.

 
They will be kept in containers for the duration of their time, Sweden is a bit too cold to have cucumbers right outside, so they'll be in a green house. I'm not really sure what you're referring to with the pinching effect, could you elaborate a bit? I've actually staked my cucumbers for now, I plan to buy something that they can 'climb' up into. 

 

[boostdemon]

hej hej! I think they look fine. I wouldn't worry about those bottom two leaves. The one that you have thats a little yellow might be from overwatering but i dont see a lack of nutrients on the new growth. Its tough to tell because you took the picture right after watering. The "pinching" he mentioned is when the branch presses against something like the side of the pot and puts a crease in it. That will cut off nutrient and water paths to the leaf.