[doug hutch]

    having just joined a leek club as a newbie ive been told to use basic top dressing
      around each leek what is btd and how should it be used

[BabbyAnn]

what is btd and how should it be used

apparently it is a "base & top dressing" (BTD) fertiliser:

see http://www.gardendirect.co.uk/chempak-specials

"CHEMPAK B.T.D. FERTILIZER

Chempak B.T.D. (Base & Top Dressing) is an example of the new modern all-purpose products, used as a compost base, spring base dressing for all plants and top dressing throughout the Summer months.

Its analysis, N.P.K. 6-8-10 plus trace elements, approximates to the old J.I.Base formula. A distinct improvement from this is achieved by having four distinct phases of nitrogen release providing a steady flow of this most important of plant foods. The fully balanced formula is achieved by adequate supplies of phosphates and potash"

It gives more information as you read on.

[cooperman]

tmi
just chuck some Growmore round 'em....

[viettaclark]

Heavens! How complicated!
Blood fish and bone and/or chicken pellets, homemade compost, comfrey tea for nutrients and manure for soil condition.
Actually THAT'S quite complicated too AND I put a sprinkle of potassium sulphate round later in the year!
Probably cheaper though....

[DD.]

I dib a hole and drop them in. Never have given them any extra, they usuallly go where the spuds were last year that got a lot of manure, they grow big enough for our culinary purposes, but I'd probably get laughed out of a leek club. 

[lacewing]

I have always done the same as DD, and have had good enough results. This year though, I thought about taking out a trench, then making holes and back filling as the leeks grow, hoping to get a longer blanch. Anybody tried this method?

[Swing Swang]

Never trenched, but always dib deeply - about 10" which works for me

[Robster]

Same as DD.  Dib deeply, toilet roll liner, in they go.  A sprinkle of growmore when I remember, and weed.  Don't suppose I would pass the entrance exam for the Leek Club

[JayG]

Only my second year of leek growing so still experimenting (although I was pretty pleased with last year's results.) 

35 of the 50 are now in individual dibbed holes probably averaging 7" deep (depending on how much soil fell in before I dropped the leek in ( ), the other 15 are quite closely spaced in a 9" deep trench which will also be allowed to fill in naturally.

I'm expecting the individual ones to be the biggest but possibly the trench ones to be the most productive for the space taken up (neither are at all likely to get me through the door of any leek club!)