The fertilizer attachment looks like:
It's the top piece, the bottom thing with the blue lid is a battery operated timer. Just a cheapo from HD where I got the timer. You unscrew the cap and put the dry fertilizer in and off you go. No instructions though!
I would like to avoid the clogged head so I think the pump spray may be a good solution. I probably will have issues with hard water deposits over time - no need to speed that up with fertilizer gunk. The rainwater idea is too much work to even contemplate.
Next questions then: if I go with a pump sprayer, do I just follow the directions for the fertilizer on strength mixing (such as 2 tablespoons per gallon) and then just spray that on the plants? How much do I apply to each plant (or maybe thats 'how long do I spray each plant?')?
JenS - They are in direct sun from about 11am - noon to around 6 pm in the summer but I think the screening on the enclosure actually cuts down on the amount of direct light falling on the plants as the day progresses as I don't have any issues with sunburn. So far, no issues with any vandas, mokaras, ascocendas or schromburgkia and the like we've put out.
In the past, we were losing too many blooms to the uneven rains we get (although that hasn't been an issue lately), the 2-3 hours a day of direct sun they were getting (followed by too much shade) and my uneven travel schedule for work the was interfering with my plant time! Between the consistent watering and the better quality sunlight this setup gives, we're actually getting buds on plants that have not bloom in 3-4 years. I am actually beginning to think that I will be able to get a Schom. tibicinis to grow well and, maybe, actually bloom... we can dream can't we?
Thanks all for the feedaback.