Cucumber seedlings turning yellow...

[The Bearded Farmer]

I have 8 cucumber seedlings in my coldframe that are very yellow in color. They have nice stocky stems and good looking leaves but the entire plant stem, leaves, and all are yellow. They are not wilting at all.

Am I correct in assuming it could be lacking nitrogen or I am overwatering??

[rainbowgardener]

Overwatering is the best first guess, I think.

Tell us more about the soil they are in, the pots (peat pots? they are notorious for holding too much water), and how you are watering.

[The Bearded Farmer]

They are in 3in pots in nursery flats sitting in my coldframe (not much outside water). The temp is roughly 85 most of the time.

The soil is a mix of soil from my garden and a small amount of sta-green garden soil.

[rainbowgardener]

3" plastic pots?

garden soil is a bit heavy and moisture holding for small potted plants. Potting soil would be better, lighter and faster draining.

And how (how much, how often) are you watering them. In nursery flats sounds like bottom watering? That is best...

[The Bearded Farmer]

Yup... 3" square plastic pots in a nursery flat that holds 10 pots. I have 5 of these in my coldframe with tomatos, peppers, chives, and a few sunflowers.

I pull each flat out and spray with the hose until the water comes out the bottom of the flat. I try to keep the water on the soil only as much as possible .

I've been checking them every day and I water about every 2-3 days. All the other plants look fine except the cukes and the sunflowers also have a slight hint of yellow too.

Did the same last year in spring and fall when I had plants in there and had no issues.