On Thu, 17 Mar 2011 21:39:24 -0400, "Gary Brown"
wrote:

Hi,

We will be away for a while - much longer than our houseplants
can go without water. Is there a watering mechanism that will
work for three weeks so we needn't have anyone come in?

This gets high ratings from Amazon customers:
http://tinyurl.com/4upanc4