Question: The first time that I brewed with whole flower / leaf hops, my more-experienced homebrewing friend said that I should have more wort than usual at the start of the boil, because the dried leaves will reconstitute and absorb liquid. I followed her directions, and I was pleased with the ultimate result. Naturally, I forgot her exact directions.

These are the [hops](http://www.oakbarrel.com/beermaking/hops_flower_chinook.shtml) that I'm using.

Is having extra wort a proper adjustment for these types of hops, and if so, how much extra wort should I have?

Answer: 
An experiment to determine wort absorption by whole leaf hope is described [here](http://www.homebrewtalk.com/f12/leaf-hop-absorption-measured-241469/). The conclusion was that an ounce of hops absorbs 0.15 quarts of wort.
Dried leaf hops absorb 4-6 times their own weight in wort. So, if you add 4oz/100g of hops in the boil, that's in the region of 16-24fl.oz/400-600ml of wort that you could lose. Naturally, the losses become more significant the more hops you add to the boil.

Most brewers intentionally overshoot slightly on the batch volume, e.g. target 5.5 or 6 gallons for a 5 gallon batch. If you're brewing a beer with 8oz/200g or more of hops, then use the numbers above to compute the additional volume needed to counter the losses.