Thanks Bella! Yes, I too give them more water than normal when I'm headed out of town just to ensure that they don't dry out. Otherwise, their trays only have water for a few hours at a time until the soil is moist at the top and then I dump it out. I do that once very 10-14 days or so in the winter and every few days in the summer depending on how hot and dry the weather is. With this cool spring here in Ashland, I've only had to water them every 5 days or so thus far.
I now use a mix of 50% peat, 30% silica sand and 20% perlite. The sand seems to make a huge difference in oxygenating the roots and promoting a very healthy root system.