Shock. Plants get shocked really easily. What they love is to have water directly down into the soil about the same temperature as that soil.
You've got the idea of a slow watering, but there are other, easy methods you could try. I'm in the process of making long PVC wants that go into the pot. I put peanuts in the bottom of the pot, or pebbles or pea gravel, then my soil and plants. Inserted into the pot on an angle is a piece of PVC pipe 1/2-3/4" wide, it goes right to the bottom of the pot, but angles from the middle of the pot (at the bottom) to the edge at the top. I cap the bottom, then drill the tiniest holes (one only in the cap) all along the sides - slow drip deeply into the pot. Easy to water and even to feed.

OK -an excellent objection i hadn't thought about.

i like your alternative wand method of watering hanging plants, ggg! thanks for the clear directions. min

I actually think it's a great idea, and would let me be more consistent with the fertilizer from plant to plant. An ice cube is not going to shock a plant...there is no way it could drop the temp of the soil that much. I have frequently dropped the leftover ice in a drink into the nearest potted plant on the deck, and have seen large potted plants in buildings watered with ice.
I'm going to try freezing the fertilizer today!

I'm sure you've thought of this, but I would be afraid that someone would accidentally ingest those ice cubes (I am thinking a pretty blue-green color like Miracle Gro). If there is no one at all or no way they could make that mistake, I still think it's alot of trouble and energy (yours and electricity). I've always heard to water the plant first and let it drain through, then water with the liquid fert. Not sure if that keeps it from running through. You could change to a pellitized fert that is slow release, or you could perhaps fill a 'baggie' (ziploc type bag) with a small hole in the bottom, fill with the liq fert and place in the pot?

mytime, don't forget, some of us live in very hot climates. In a hanging basket, without a single day of water my plants are dead. They really have a hard time in a hanging basket even handling full-day sun,the contents is well within the 100 degree mark daily (or higher) for very long periods and some of us get very little cool down in the evenings.

girlgroupgirl, I understand about your temperatures (I've been to Atlanta in the summer--never again!), but that is even more reason that an ice cube won't shock your plants. If anything, cooling the soil might be beneficial (except for the fact that the temp. won't be changed by an ice cube or two).

No, really it does shock them. One of the #1 tricks of the nursery trade is to use water that is kept at the same temps as the plants for watering. Freezing stuff on a regular basis is going to retard growth and it can cause the plants to simply keel over depending on the plants.

I always wonder about water temp when watering. It's easy enough to control from inside the house to a watering can. But the outside hose is a different story.

I would be concerned that the ice cube would roll up against the plant.

I do this for orchids all the time.

I used to work for an elderly lady that used ice cubes as a means to water her gardenia bush that she kept inside as a houseplant, but put it outside on her patio in the summer.

well thanks everybody for all your thoughts!
there doesn't seem to be a consensus on my idea here but i am going with those of you who think it might work. to test it out, i should get two identical plants and use ice fertilizer on only one of them... but i'm not that much of a scientist. i think i will just try it on my plants for the summer and see what happens. if they all keel over, i will let you know. (-:
min

I certainly don't argue with the fact that for actual watering, non-ice water is best. But I've been doing some research, and some plants apparently do better with being watered with colder water. That said, I think part of the controversy here stems from how much water will come from ice. I envision very little of the actual watering coming from ice. If I get around to it today, I will test the effect of ice cubes on soil temperature in a pot. I would bet money that it will be extremely minimal. I like to test things out...