[MickyB]

I have been trying to grow some winter cauliflower from seed but keep failing, the seeds germinates and the plants grow to around 4cm produce two small leaves then die 

My thoughts on why....

1. Too hot in the greenhouse? - I have moved them to the outside.
2. Over watering? I only watered them once a day? Now trying less water.
3. Too early to try - given the weather?
4. They die of shock when they hear me singing to them?

But I dunno - any idea's?

[devonbarmygardener]

I had this last year with a lot of my brassicas.

I now sow more than I need (in good seed compost) - literally loads - I give the rest away.
I also grow them outside - my plot neighbour can grow anything in her greenhouse - I can't

[Annen]

Mine haven't exactly died, they are outside, but they don't look very happy, they have got to four leaves and then stopped and have been the same for a couple of weeks now.  I'm thinking it might be too warm for them.

[MickyB]

I was hoping to get them going in decent sized pots before planting out to give them a fighting chance against club root which proved to be a problem this year.

[mumofstig]

Mine haven't exactly died, they are outside, but they don't look very happy, they have got to four leaves and then stopped and have been the same for a couple of weeks now.  I'm thinking it might be too warm for them.

Try giving them a half strenth liquid feed, to start them growing again. Compost very quickly runs out of nutrients and seems worse than ever this year  have you got anywhere a bit shadier to put them?

[goodtogrow]

Agree with mum about the compost, but also don't know why the seedlings need greenhouse conditions at this time of year, leading to more watering and loss of aeration in the mix, from more watering.

 I do not believe that peat-based composts deliver what they claim.  They're lovely to handle, and look lovely, but behave badly, from the seedling's point of view.

Always wondered why we even begin to believe that nutrient level in shop-bought compost is evenly distributed throughout.  Isn't it just possible to get a duff bag, with little or no nutrient, or a too-heavy concentration in some of it?

Tom

[RJR_38]

I thought brassicas didn't like heat and greenhouses?...

[mumofstig]

I thought we'd already agreed that ....................Brassicas should not be in the greenhouse !

 

Outside - with some shade while the weathers still hot, would be ideal 

[MickyB]

.....Outside - with some shade while the weathers still hot, would be ideal 

OK that's where I have them now, lets see how they go. 

[Annen]

Try giving them a half strenth liquid feed, to start them growing again. Compost very quickly runs out of nutrients and seems worse than ever this year  have you got anywhere a bit shadier to put them?

Thanks Mum, I will try that.  I sowed 5 in 5" pots this time so they would have a good root development and I have learn't my lesson about keeping them in the greenhouse from previous failures. But I haven't given them any extra feed. They are in semi shade at the moment but I can move them easily.

[JayG]

Always wondered why we even begin to believe that nutrient level in shop-bought compost is evenly distributed throughout.  Isn't it just possible to get a duff bag, with little or no nutrient, or a too-heavy concentration in some of it?

I've mentioned this before (probably more than once!  )
My suspicions have been growing over the last couple of years about the nutrient levels in MP composts - I have experienced poor growth right from the word go (rather than after the usually-quote 6 weeks) with two different brands of compost in that time.

Liquid feeding as soon as I suspected growth was sub-standard for the type of plant and time of year rescued the situation, but of course you shouldn't have to do that. 

[goodtogrow]

It comes as no surprise to learn, JayG, that experienced growers have long suspected what I've concluded from my own wild imaginings 

[JayG]

Not sure about that GTG - it might just be you and me!   

[devonbarmygardener]

I have seen a difference this year in buying a really good seed compost rather than just basic MP - might be a little more expensive (although I have a variety of garden centres to weigh up and get the best offers in ) but worth it in the end

No brassica failure this year

[Annen]

Try giving them a half strenth liquid feed, to start them growing again. Compost very quickly runs out of nutrients and seems worse than ever this year  have you got anywhere a bit shadier to put them?

Thanks Mum, I will try that.  I sowed 5 in 5" pots this time so they would have a good root development and I have learn't my lesson about keeping them in the greenhouse from previous failures. But I haven't given them any extra feed. They are in semi shade at the moment but I can move them easily.

Thanks for the tip, Mum, it worked a treat, two more leaves on already