Small Kale and Chard (Again)

I have no idea what the secret is to growing Winter leaf veg such as Kale and Chard (supposed to be easy) but after a promising start from seed in late summer they are planted out and now they are like Bonsai trees. The leaves are smaller and the plants have got shorter. I fed earlier with Blood and Bone as well as chicken pellets. 

What can I do to get them more productive. This happened last year and it's frustrating as I made sure I have a few plants this year but even harvesting all of them wouldn't be enough for one meal.

Is there anything attacking the roots?
Otherwise just leave them....they take quite a while to thicken up. My Swiss chard was planted out in June and is only now getting darker larger leaves!

I sow mine from seed late April or early May and have big plants now.

I sow swiss chard in spring and plant out early july/late june at latest, did try latter sowing this year aswell but they not done well.
I find if you keep harvesting and cut any flower shoots as soon as they appear they keep going through the winter, hope this helps

I have plumped for both Kale (Black Tuscany) and Chard (all types) for my winter leaf this year.  They were sown early May and went in late June.  I have been lightly harvesting chard since August and havent touched my kale yet.

However, both suffered a check in growth towards the end of September and the pigeons decimated the kale.  I gave them a blast of nutrients with chicken pellets and gave the chard a severe pruning of all yellowing and damaged leaves, and stripped off any yellow kale leaves.

Since then they have gone crazy.  The Kale is going to get it's first harvest for dinner tomorrow, along with some more chard.

(The only other problem I have had this year is that all my Ruby Chard bolted, whilst none of the other colours did).

I have had the same problem with ruby chard bolting, none of the others have though.