No, not that kind of vegetation. You're a writer, you're not allowed to go outside (Happy 4th July, Americans ;P).
That said, you are allowed to spend a certain amount of time vegetating. As previously discussed, writers are awesome brainy people who spend their 'on' time braining very hard indeed. Well, a person only has so much braining in them per day, and it's important to take breaks so you don't burn yourself out.
But taking breaks is dangerous; there are all sorts of breaktime activities which will kill your productivity if you take too many breaks or let them run too long (never, never, never, take a break to read a book, because 'just 5 more pages syndrome' will ruin you). It's important to strategise your breaks to avoid this. Taking efficient breaks will make a huge difference to your work rate.
You need to pick activities which fit your ideal break length. One thing that works for me is playing the piano. I tend to play pieces in the 6-10 minute range, and two or three of those make a very neat break, just enough to settle my mind and let the next few thoughts fall into line. That fits quite neatly into the half-hour-on, half-hour-off pattern of #wordmongering (which I highly recommend).
This weekend, I found another trick, one that might sound incredible to some. Here's what I managed to get done between yesterday and today:
Cohlin is the city in which 'Heaven Can Wait' is set. I've been working - painfully slowly - on this map for about a week and a half, but I did well over half the work in the last 24 hours. Why? Thanks to one of the most addictive videogames ever created.
I'm speaking of Minecraft. The first time I tried Minecraft, I spent a week doing nothing else. It was fun in a vacuous sort of way, but it's time I'm not getting back. This time, however, I alternated 10 minutes of map-drawing with 10 minutes of Minecraft thanks to the game's day-night cycle.
I'm not saying this will work for everyone or every task, but it was perfect for this one - it allowed me to work in short, intense bursts and kept my playing very thoroughly under control because if I stayed outside at night in-game, monsters came and killed me (death threats are, as ever, pretty effective motivation).
Anyway, the golden rule is that you have to find what suits both you and the task. How big is the task? How frequently can it be interrupted without you losing the thread of it? What do you do that rests your brain?
Also, do you like my map? ;)