Does Ice Over Plant Roots Make Them Go Dormant?

Question from Bob:
I have heard of placing ice cubes over the top of the plant locations at night to give them that additional chill, is there any sound meaning to this.

Answer from Pat:
You asked me if it works to put ice over the roots of rhubarb in winter in order to make the plant go into dormancy as if it were being grown in a cold-winter climate.

I have heard many times of people in California trying to trick peonies this way. Sometimes people tell me they know someone who did this with success, but usually a question or two discloses the fact that they live in a cold pocket like Ramona or the foot of Mount Baldy where frost is a frequent winter occurrence. As I’m sure you know, it’s common practice in California to fool hyacinth and tulip bulbs into thinking they’ve gone through a cold winter by refrigerating them for a month or six weeks prior to planting. Additionally, I explain on page 362 of my book how to dig up, bare-root, and chill strawberry runners in the refrigerator and then on page 383 I tell readers how to plant the pre-chilled runners around November 5th so they’ll begin producing berries six weeks later.

I suppose you could dig up your rhubarb plants in November, bare root them, wash and then dry the roots, cut off most of the leaves, and—If you have an extra refrigerator with room for this experiment—put the roots into your refrigerator for six weeks or two months and plant them out again in early January (after the winter solstice.) So, no, I don’t think ice over the roots would be adequate to make your plants go totally dormant, but chilling the roots in the refrigerator (not the freezer) might do the trick. But what a bother to go through all that hassle! Would it be worth it? Only you could decide. I’m not advocating you try, only suggesting what might work.