Growing brassicas from seeds

[julia3]

I've tried to grow cabbages, brussel sprouts and broccoli a couple of times from seed in an unheated greenhouse. They germinate ok and get 2 leaves and then keel over and die. What could I be doing wrong? This has happened twice now. Also, if I ever manage to keep them alive, at what stage should I transfer them from the seed tray to pots?

[rustylady]

Best guess is that your compost is too wet. How many plants do you need? I generally sow mine either 2 seeds per small cell and leave them there till ready for planting out, or around 8 in a 3and a half inch pot. Transplant from there when true leaves appear, again into individual pots.

[bridget mc laughlin]

I just buy all my brasicas as seedlings, I 'm just too lazy

[terrier]

I've got some cabbage seedlings coming up now, very tall and thin. I suspect just not enough sunlight for them at the moment. They're taking their chances in a cold frame.

[Eyren]

Def sounds like damping off (a fungal disease) if they die at that stage. Are you using fresh seed compost? Also, as mentioned, don't keep watering them too often, and don't cover the seed tray - brassicas like things on the cool, dry side.

This site has lots of useful info on pests and diseases:

Damping Off - its symptoms, causes and treatment

[julia3]

Thanks, thats very helpful. This time I've made a point of getting new compost, clean seed trays and kept the watering to a minimum so fingers crossed it will work out otherwise I'll be reverting to the lazy solution too!

[Two_Sheds]

If you're only growing a few, might be as cheap to buy plants as to try and raise your own from seed.

[zazen999]

Interesting; I posted on here yesterday about mine being dry for ages and thriving; and it's been taken off?

[tootles]

I have sown broccoli, cabbage, cauliflower and beetroot. 3 seeds per 6cm pot and left them in my unheated greenhouse/polytunnel thing and they have done brilliantly (but kept quite dry) I have since planted out half of the seedlings to see how they fare - with the spares in reserve if it all goes wrong! My little seedlings woke up to 2" of snow yesterday and are fine!!! Even lettuces and peas....
I would say to persevere with the seeds - it is much more satisfying!!
Tx

[skiprat]

agree with Eyren - its very easy when its cold to over water especially in unheated greenhouse. Do you use recycled water (ie water butt) to water your seeds? I find its far better to use fresh tap water to water seedling as there is less likelyhood of picking up something which harms seedlings.