Dying plants.

[goosander]

Looking for some help/advice please.
A lot of my cucumbers/melon/some types of toms and a few other things are just giving up the ghost. They start off looking well and then over a few days they just lower there heads and die. Have soil warming cables in and keep them watered but not to wet.
Thought I was beginning to learn something but back to the start.
Thank you.
Bob.

[veggiechicken]

What about the air temperature? Have you had frost?

[quanglewangle]

Could be damping off? Look at stems where stem enters soil. Look for narrowed stem and fungus filaments - may need a hand lens to see.

[greenishfing]

Is the air too warm and dry? I have had plants with similar symptoms on the windowsills above radiators in the past.

[nickdub]

Most likely to be a soil born disease, like damping off as already suggested.

Small plants are vulnerable - clean all containers thoroughly first. Use new compost or sterilise some older stuff in a microwave. Use tap water not water from a butt (unless you can be bothered to boil it first), and water from the bottom by standing the containers on a tray or whatever.

If you want to post some photos, then we should be able to give you a more definite answer.

[Bren In Pots]

Could they be just to cold to survive.

Ps I’ve fixed the title.

[ameno]

It'll either be damping off, a root rot of some kind, or fungus gnats. I had real problems with the latter last spring. They ruined two batches of cucumber seedlings.
Look for tiny dark flies on or near the compost surface. If you see them, it's probably fungus gnats. If you don't, it's probably one of the others.
Either way, dump the pots outside and sow new seeds in fresh compost. Don't let then stay too wet, and if it was fungus gnats, put up one of those sticky yellow traps to try and catch the adults.

[smallblueplanet]

A lot of my cucumbers/melon/some types of toms and a few other things are just giving up the ghost. They start off looking well and then over a few days they just lower there heads and die...

Got any pictures?

[goosander]

Thanks for all your help.
Had almost 100% germination with Marketmore cucumbers about 30 plants and was wondering what I was going to do with that lot. Down to 2 now. The plants seam to fail at the leaves and just left with a tapered stump. All compost is bought in fresh [seed sowing with sand] and the greenhouse is emptied each backend and sulphur candles lit. Have been doing well up to this season. Unable to send photos.[Only person on the planet that refuses to have one of the fancy phones]
Bob.

[smallblueplanet]

Thanks for all your help.
Had almost 100% germination with Marketmore cucumbers about 30 plants and was wondering what I was going to do with that lot. Down to 2 now. The plants seam to fail at the leaves and just left with a tapered stump. All compost is bought in fresh [seed sowing with sand] and the greenhouse is emptied each backend and sulphur candles lit. Have been doing well up to this season. Unable to send photos.[Only person on the planet that refuses to have one of the fancy phones]
Bob.

Is it a heated greenhouse? I can't see how you're keeping cukes warm and light enough, or the soil is too cold and damp? We had frost again overnight.

[goosander]

Have a heater that keeps it just above freezing but have soil warming cables and the beds are covered at night with polycarbonate from an old conservatory.
Bob.

[smallblueplanet]

Have a heater that keeps it just above freezing but have soil warming cables and the beds are covered at night with polycarbonate from an old conservatory.
Bob.

Still think it'll be too cold and damp, but maybe the only way to be sure of the cause is try some in pots and bring them indoors at night? Or just as they are now but in 2-3 weeks time?

Or if they're all in the same compost try a different one?

[rary]

^^^^^^ I have tomatoes, cabbage, onions and various flower seedlings in the greenhouse without heating the temperature has been at - 2c and the plants are all looking OK I cover them at night with fleece and have a fan running continuously, I never water at the top of the pot, now I just hope I don't need to come back on here and say I have lost them

[goosander]

Sure now that some of the problems must be to cold at the pots base. Shifted some and the pots were cold.
Last year I did not have this problem and left the soil warming cables in all season.
Bob.
[P.S. bought more packets of seeds to make up for loses [73 pkts. total.]]

[veggiechicken]

73 pkts to make up for losses.
You don't have to make excuses or explain your seed buying weaknesses to us.

Hope you have better luck with your next batch of seedlings. I'll be sowing some toms and cukes this week too, now that spring is on the way.