Yes, you will go on vacation. And yes, your orchids will still need to be cared for while you are away. And this can be a challenge. Because not everyone who volunteers or can be co-opted to plant-sit or house-sit has your appreciation for orchids. Nor necessarily your patience with their care.
Trust me, I know. I’ve gone on vacation with explicit instructions on the care of EVERY orchid. I’ve even gone so far as to put post-em note on select plants. This one “don’t water” while I’m away. This one “keep feet wet”, which means keep water in the saucer, unlike most orchids which should be thoroughly drained before being returned to their usual perch.
when I had fewer orchids I remember a vacation we took where I watered all the orchids thoroughly, put an inch of water in the bottom of the tub, set all the plants into the tub and closed the sliding glass doors. The closed glass doors kept the humidity high and slowed the drying of the water in the bottom of the tub. The plants did fine. Even though many of the orchids need to try out (more or less – some more, some less!) on a regular basis, being kept too wet occasionally for longer than normal is no big deal. They will do MUCH better staying too wet occasionally than drying out too much for too long.
Now that I have a lot more orchids, if I need to miss one of the waterings, I can put water in all of the saucers under all the plants even though they will no longer all fit in the tub at one time. As the water dries naturally it creates higher humidity in the vicinity of the plants, and the water in the saucers will wick up into the bark and keep it moist longer. Missing a watering will get me a week’s vacation with my wife without needing to have the orchids watered. If we are going to be any longer than that, unfortunately, they are going to need to be watered by someone. But again, it’s possible to cheat a little. Even though I very strongly believe that each orchid should be watered thoroughly in the sink and not watered like traditional houseplants – where someone uses a watering can to pour some additional water on the soil – again, they can survive an occasional improper watering. So you have a choice to make.
I’ve tried it both ways, having someone simply water in plant in place with a watering can, and teaching someone to methodically take the plants one at a time to the sink and watering each thoroughly. That latter is preferred if you can find someone who will do it. The care of your plants will more approximate the care you give them. But most orchids are pretty resilient and can withstand a little abuse, even if that’s in the form of poor watering practices for a week or two.
Either way, I suspect the occasional plant has been missed. Maybe I’m just paranoid, but there are some obvious signs of too little water – limp leaves on Phals, shriveled pseudobulbs on Oncidiums and other orchids with similar bulbar growth habits. Some of these changes are temporary. I’ve seen Phal leaves firm up when watering is resumed correctly. Shriveled pseudobulbs, however, don’t ever change. The plants can stay healthy and productive, and new growth will be normal with normal watering, but the shriveled bulbs will stay shriveled and will be less attractive for as long as they live.