[anchorman]

Hi everyone,
I put up a 7 metre Wonderwall mesh tunnel and intend to crop it with brassicas. Sprouts, cabbage and Cauliflower are my aims, which I do ok with from raised plants. Last year I had about 4 attempts at raising from seed but ran into terrible, wasteful trouble due to total losses at the seedling stage. I can get good germination but when the baby brassicas are about an inch or so tall, with good seed leaves, they stop growing, slowly turn yellow and die.

I've tried less water, growing them on in cooler conditions in a cold greenhouse, putting them outside but sadly all meet the same frustrating slow demise.

Obviously, I'm doing something very wrong but I am missing something. Other growers I know cant see what all the fuss is about. They have acres of allotment full of home reared plants.

I have read that this is a common problem but have yet to find the knack of bringing them on to healthy plants.

Can anyone out there point me in the right direction?
I will be very receptive to advice.

Thanks.

Anchorman 

[mumofstig]

They don't need heat to germinate, start them off in a cold frame/unheated greenhouse in Spring - or outside when the weather is a little warmer. Moving from hot to cold can kill them.

They shouldn't need any feeding until they've been growing in the compost for about 6 weeks - but there have been a few bad batches of compost recently.

[Annen]

Mine all died like that too until last year when I got fed up faffing around with them and put the seed trays out in the garden from the beginning.  Mind you, you have to watch out for birds then.

[Goosegirl]

Are you sowing them too thickly so they then damp-off? I put the seeds individually in pots and they do ok. It also could be the compost. I do use multi-purpose but like Been-and-Queued Verve, although any good one should work - there is a thread on here about compost and it's always worth spending a bit more on a good one.

[sunshineband]

It may well be the compost -- I had real issues with germination and the first stages of growth with Wickes' mpc. Best to buy a decent one. Verve or jacks Magic is often recommended and readily available.

[anchorman]

That wee crop of advice sounds sensible to me folks, thanks.
Last year I started them all off later in an unheated greenhouse which gets quite hot in spring sunshine so keeping them cooler and sewing earlier should help. Today, the first ones are just begining to germinate so i've turned the propagators off and left in a cool conservatory for now. There is only minimal heat used in there on the coldest of nights to keep temp at about 7c. It's north facing so wont get any direct sun until later in the year. I hope now that the tiny seedling will harden off  bit before putting them in a cold greenhouse. Hopefully a gentle easing down of temp wont hurt as the propagators are only 8 watts giving about 16c max.

I am using Jacks magic this year so hopefully that will help too.

I sow individually in modules so that should reduce the risk of damping off.

In a few days I should know if the already germinated seedling are ok. If not , I will go again with no heat. I might just have saved them if they dont check.

I will post with progress results, cheers all.

[anchorman]

Wow! How right you good folk are. I came home from work today and looked in on the brassicas which are now out of the propagators and sitting in a cold conservatory. The baby Cauliflowers (all the year round) have lifted their curly little heads up and look healthy. Pleeeeze keep going now.

[devonbarmygardener]

I find that if I sow the amount I want, they all die regardless!! 
Now I sow loads and give the other plants away

[anchorman]

Hello folks, all is busy on the plot but i think something is going wrong with my Cauliflowers, all the year round variety. They've been growing for about 6 weeks now and are very small. Seed leaves are dying but first true leaves are looking ok. Other brassicas are much bigger but even they seem small for their age. Any ideas what will push them on a bit. They are in the cold greenhouse and the door is left open so it's not at all hot.

Help please!!!

Thanks

Anchorman

[JayG]

I'm far from being a brassica expert, but I do know that some composts run out of nutrients faster than they should, and after 6 weeks it's probably worth trying a liquid feed to see if that livens them up.

[sunshineband]

Something with a good dose of nitrogen will help them on their way.

Seed leaves, naturally die as a plant matures, so no worries about that.

[anchorman]

I think you are both right, any Ideas of what Nitrogen compound to use? I guess it would not have to be too strong bearing in mind the size of the seedlings.

Thanks for the advice folks.

[JayG]

Miracle Grow and Phostrogen are well-known liquid feeds, although there are others. They all tend to be quite high in nitrogen (esp. MG) but also contain the other 2 essential elements as well as trace elements - given that you can't be sure exactly which nutrients may be lacking it's an easy way of covering all the bases.

I wouldn't worry too much about the dilution provided you don't feed them at every watering.

[luke34]

have you thought about using Maxicrop as a root drench

[anchorman]

Cheers folks, they looked a little perkier today having been in gentle sunshine for the day. I think I have some phostrogen. I'll give them a stand in a tray for a day, in a dilute. Dont want to saturate tho' but I figure an inch or so, just to allow some root feed to perculate up the pots a bit. I will let you know how it goes.

Thanks a lot folks, confidence in this forum is building.