Yellowing of leaves on Sweetcorn & cucumber

[dboy1988]

Hello all,

I have been growing some sweetcorn & cucumber plants inside under a grow light, they are about 4 weeks old, up until recently have been very green and growing well, the last couple days I have noticed the yellowing of the leaves around the edges shown in the screenshots and I was hoping I could get some advice about what could be the cause.

Thank you

[Jungle Jane]

It could be the nutrients in the compost is lacking if it’s been 4 weeks,causing the yellowing. Have you got a nitrogen fertiliser,I use a seaweed feed that contains a small amount of nitrogen & others. The natural sunlight will be better for them if they can go outside or by a window.
Check the temperature tho,I wouldn’t leave them out overnight yet……

[peacegarden2024]

looks like you need more light and more nitrogen fertilizer.

[Jungle Jane]

I’ve noticed that my compost this year doesn’t seem to have many nutrients in it,things like pepper leaf drop,yellower leaves on tomatoes & peppers. Courgette older leaves look like they’re feeding the newer leaves,the new leaves are great but the older leaves are feeding them. So fertiliser is the answer but diluted for young plants,I use half measure so I use one capful instead of two capfuls for ten litre watering can.
Also my compost contains more wood than usual & this feeds on nitrogen as it decomposes….

[Muddy_Boots]

You could use a quick hit to solve the initial problem like watering in a sprinkle of fish blood and bone or even use a soluble food like tomorite watered in, then put on a sprinkle of growmore granules on the surface (not too many) that are slow releasing to keep the nutrients being delivered for longer until you repot into larger pots.