What is this deficiency /toxicity? Pumpkin plant.

[danny.]

Hi.
I'm new to all this and I'm having trouble with my pumpkin plants. Basically they're not looking good. I have three Atlantic Giants growing in grow bags (I'm not aiming for a world record, just a family competition between my father and I).
In the name of science I planted each plant in a different brand of compost tosee if it made a difference in the end.
My best plant is growing in a growise (john innes) multi purpose.
My 2nd plant is in a Vital earth vegetable compost.
My worst plant is in a Miracle gro vegetable "gro sack".

All of the plants started well but in the last 3 weeks or so things have gone down hill. All the plants look pale green/yellow with the older leaves dying off although the one in the John Innes is looking the greener of the bad bunch.
The one in the miracle gro is terrible, aswell as being pale the new growth is covered in deep yellow patches.

All plants have been fed the same fertiliser from the same watering can which was Maxicrop seaweed extract and Doff organic plant feed (NPK 525).
I thought the problem could be Mg deficiency so i tried adding epsom salt to their twice a week feed but it hasn't helped.
I then changed my maxicrop original and started feeding the maxicrop plus iron but that hasn't worked either.
I'm worried that all my plants will die.





What do you suggest?

Thank you.
Regards,
Danny.

[Potstubsdustbins]

Google verticillium wilt see if that fits the bill.

[bearded bloke]

Could well be excess nitrogen, try a feed ratio 5/15/15

[Snadger]

Looks to me like they are short of water?

PS because the John Innes is a soil based compost it will naturally hold moisture a bit longer which could be why they are doing better in it?

[danny.]

Thanks for all the help so far.
I dont think it is verticillium wilt going by what I've just read but thanks for suggesting it.
I dont think its lack of water either. The compost is overly wet if anything due to the weather. That is what made me think it was an iron lockout.

I have been foliar feeding using the seaweed plus iron, should i keep at it and see if things improve?

If it is an excess of nitrogen should i just flush all the growbags with a hose?

Thank you.

[mothhawk]

If you've had a lot of rain, they will probably perk up again after a few sunny days. I wouldn't add any more water by trying to flush the soil if the compost is very wet. They need to dry out a bit till the compost is nicely moist, not soggy.

[Snadger]

I still think that its asking a bit much to grow an Atlantic Giant pumpkin in a growbag. One plant in the bedsoil of my 10 foot by 8 foot polytunnel has filled the tunnel with foliage.The plant goes through 5 gallons gallons of water per day and still cries out for more.. There's no way that the amount of leaves a pumpkin has and the transpiration from them can be accommodated in a growbag IMHO.

[cptncrackoff]

Hi, I read your giving a foliar feed.
That's probably not linked to your problems but all members of the cucurbit family..cucumbers, squashes, pumpkins, courgettes etc don't really like wet leaves, frequent watering of the leaves can cause the plant to 'drop fruit.

My Atlantic giant and freaky Tom plants are now dying back, and the fruits ripening...
I just put this down to the days getting shorter and the plants biological clock!?

[danny.]

Ok thanks for the info. I'll just leave the plants alone then for a few days and see if things pick up.

I know that growing an atlantic giant in a grow bag is not ideal and that the plants will be stunted by it, but its just a bit of fun really. Not looking for actual giants, just something big enough to carve at Halloween and hopefully bigger than my dads. Purely for bragging rights

[jacob]

Curcubits just do that in containers, running out of everything nutricious. Where are you? It's not really been pumpkin weather up north this year.