Growing Ice - An Overview  

Dr. James R. Carter, Professor Emeritus

Geography-Geology Department

Illinois State University, Normal IL 61790-4400


This page was put together in 2012 support of a radio discussion of my world of growing ice.  As such it gives a quick overview of the many types of ice discussed on my other web pages starting at  


Ice Flowers - Growing on Plant Stems

I found my first ice flowers on a hike in east Tennessee in late December 2003.

Figure 1 -- Two photos of the first growths of ice I ever saw.  These photos were taken in late December in east Tennessee, USA.  These growths are at least 4 inches or10 cm in length.  I think the ice formations are on stems of Dittany, Cunila origanoides.  At the time I took the photos I did not appreciate the need to make more observations.


I found the ice ribbons below in northern Kentucky in November 2005.   

Figure 2 -- Ribbons of ice on cut-off stems of White Crownbeard, Verbesina virginica, in northern Kentucky in mid-November 2005.  Part of the beauty of this photo comes from the interplay of the white and green on the various shades of brown.  Here the ribbons of ice are quite massive.  Note the fringes of white frost on the edges of some of the leaves.


I found seeds of White Crownbeard and planted them in my yard, in big black buckets.  In fall 2007 I had ice growing on the stems of these plants.  below.

Figure 3 -- Three photos of ice on White Crownbeard Verbesina virginica in buckets in my yard. Left, on November 7 ice extended far up the stems. In the middle, the ice that formed November 23 was more full, but did not extend far up the stems.  The ice of December 4 is smaller and closer to the ground, right. Note how the forms of the ice flowers change throughout the season.


In spring 2008 I planted seeds of White Crownbeard in the buckets and in other places in the yard.  In late October I found my first ice.  

Figure 4 -- Three different forms on ice in my yard in 2008.  The two images to the left are on stems of White Crownbeard, Verbesina virginica in November.  To the left, looking down along the stem ice has grown out to form a scoop.  In the center we see how ice has grown out along the length of the stem but has then fused together to wrap around the stem.  The image on the right is on a stem of Victoria Blue Salvia and formed in late December.  This ice flower measures 2 inches, 5 cm, across at the widest.  The two ribbons of ice on the left were somewhat larger.


I have continued to grow White Crownbeard in my yard and some years have had better ice than other years.  Below I am kneeling beside a bed of the plants.  This photo shows the relative size of the growths of ice.  Note the bricks bordering the bed are 8 inches long (20 cm).

Figure 5 -- The photo on the left was taken on December 7, 2011.   The ice formations in this bed were larger earlier in the season.  On the right is an ice ribbon from that fall.  That year I had many colorful leaves in among the ribbons of ice. 


I refer to the ice that grows on plant stems as Ice Flowers and Ice Ribbons.  There is no widely accepted term.  One person has proposed the name Crystallofolia - meaning flowers made of crystals (of ice). 

Based on correspondence with persons who have seen my pages, I know of about 40 species of plants around the world which support the growth of such ice.  This occurs when the moisture in the ground is still liquid, but the air temperature has fallen below freezing, being the process of Ice Segregation. Thus, it is most likely to occur in the morning on a fall day, but it may happen at other times when the conditions are right.  


Hair Ice - Growing from Dead Pieces of Wood

Soon after posting my first web pages in 2004 I started to get inquiries from persons who had taken photos of ice they found and wanted an explanation of what they had seen.  This is a wonderful way to find ice formations that I could never find on my own.

Below is an example of Hair Ice growing on a dead piece of wood.  I have never seen this personally

Figure 6 -- This photo by bobbi fabellano from the Olympic Peninsula, Washington, USA, distinctly shows the piece of wood without any bark on it. In the photo the hair ice seems to wrap around the piece of wood. Note the wood is not lying on the ground.

The specialist on Hair Ice is Dr. Gerhart Wagner of Switzerland.    His work shows that Hair Ice is related to the presence of a fungus that grows on a few types of wood.  Hair Ice does not appear to occur in the Midwest or the southern parts of the U.S.  Dr. Wagner and I correspond about growing ice. 


Needle Ice from Soil

Recently, I observed that some of the areas in my yard crunched underfoot as I walked across the grass early on a cold morning.  I looked closer and found many crystals of ice growing out of the top of the soil.  Four hours later the soil had warmed and the icy areas were now mud.  The next morning there were needles of ice again only to turn back to mud in a few hours.

Such ice growing from the soil is known as Needle Ice and is quite common with the right soil texture, moisture conditions and temperature conditions.  Some needle ice can be quite large, but in my yard it is a rather basic.  The conditions that produce Needle Ice are the same that produce Ice Flowers.  

Figure 7 -- Close-up photos of a small piece of silty soil in my yard in central Illinois.  I stood a Penny up between the needles of ice in the soil, but when the soil melted it turned to mud and the Penny fell over.  In some cases this process is repeated day after day if the soil remains wet and the temperatures cycle above and below freezing.


Ice Growing from Pebbles

Two persons have sent me photos of ice growing from small rocks.  Below are photos of ice growing from rocks in Missouri. 

Figure 8 -- Three examples of ice growing from rocks in the yard of Jared Wilson of Missouri.  The lengths of this ice are more than 1 inch long.  In the photo on the right some residual snow is evident in the foreground and background.  Why do a few rocks grow ice and others do not?  Photos by Jared Wilson.

I had colleagues in Alabama and Missouri send me rocks on which they had seen ice grow.  I put those rocks in the area of my yard that had needle ice.  Indeed, those rocks did grow a little ice.  It was not as dramatic as shown in their photos, but it demonstrated the process that produced needle ice also produces growths of ice on rocks. 

Rather than wait for cold mornings to produce such ice, I set out to replicate the process in a refrigerator.  I started with a small ice chest that would fit in a freezer compartment.  I put a small light bulb in the bottom to generate heat to keep water in the soil from freezing.  I then filled a plastic bucket with wet sand and placed it over my heat source - the light bulb.  I then adjusted the amount of light with a rheostat and worked to find the right combination of temperatures that might grow ice on the rocks I put on the wet sand/soil.  Sometimes it worked very well, as in the example below.   

Figure 9 -- On the left is the picnic ice chest which I put into the freezer of a refrigerator.  Note the small plastic bucket filled with wet sand and five small rocks.  On the right is one of the best examples of ice I grew on one of the rocks sent to me by Jerry Green in Alabama. 

Growing ice in my refrigerator has permitted me to try many different rocks under different conditions.  On rare occasions I get some nice growths of ice, called Pebble Ice .  I have seen ice grow on a few rocks and pieces of clay pots and brick.

We now know that the process common to all the growths of ice above is called Ice Segregation   Within a small range of temperatures, water moves to ice, freezes and adds to the ice.  This process may go on for hours and thus can produce relatively large growths of ice.


Growths of Ice in Birdbaths, Caps and Pans

When water freezes it expands as anyone who ever had pipes freezes knows all too well.  In an ice cube tray the water freezes from all sides, including top and bottom.  Look at ice cubes and you will see that most of them have a bump on the top where freezing water in the center pushed up in the only direction it could go. 

Sometimes this bump becomes an Ice Spike, as in the cap of a pill bottle below.  Such spikes have been seen by many people.  I put many bottle caps outside in the winter and on rare occasions I get ice spikes.  I also put out pans of water and examine the patterns formed at the top of the water.  Below is one example.  Note, how the needles of ice in the pan intersect to form triangles. 

Figure 10 -- On the left, needles of ice form on the surface of a pan of water as the water starts to freeze.  Note how the needles form triangles as they intersect.  On the right is an Ice Spike that formed in the cap of a pill bottle.  Such Ice Spikes are sometimes seen on ice cubes. 

As water freezes it sometimes sends up a single jet making an ice spike.  But, as shown in the photos below, sometimes a triangle of ice grows upward.  

Figure 11 -- Unusual growth of ice in the metal birdbath of Jeffrey Hutton of northern Kentucky, USA.  This triangular growth of ice measures about 2 inches, 5 cm, across.  As illustrated, it consists of three walls and is hollow in the center.  This was observed in March 2007.  Photos by Jeffrey Hutton. 


I had never seen big triangles of ice like that in Figure 11, but I have seen photos of similar ice formations from many places.  Note the similarity in the patterns of the triangles in my pan with the triangle of ice in the birdbath.  In most cases as the water freezes solid, the triangular needles disappear into a smoother ice surface.

I experimented with growing ice in a pan, with considerable success. I put pans of water on my deck. On occasion light reflecting off the wall and sky created surreal patterns of color when captured with my digital camera.

Figure 12 - When seen close up some of these reflections reveal another world. What this should tell you is to look for such ice on cold mornings or evenings. 


Extruding Ice from Steel Structures

In 2007 I received photos from Sheri Terris of Canada showing ice being extruded from a steel fence post.  I corresponded with her and she gave me permission to use her photos.   Her most impressive photo shows an overlapping ribbon of ice, reminding me of ribbon candy.

Wow, I was impressed and set out to determine how such a ribbon of ice could be made.  Obviously, water got into the fence post, froze and pushed out of a slit at the top.  Could I duplicate that process and extrude my own ribbons of ice?

Figure 13 -- Sheryl Terris of British Columbia, Canada, captured photos of ice being extruded from a steel fence.  Her photo on the left shows a long ribbon of ice that folds back on itself, like ribbon candy.  In an attempt to explain how that ice was extruded from the fence, I experimented with steel pipes and produced the two examples on the right.

 I continued to ‘play’ with growing ice by extrusion through solid objects and got many good results and broke up some pipes.


Figure 14 -- Four views of a ribbon of ice that I grew from a steel pipe.  In this case I sawed a slit in the cap of the 1 inch pipe with a hack saw. That is a red-twig dogwood in the background.


In addition to the ice extruded from her fence, I have received photos of spirals of ice extruded from posts of a steel stair railing in England, from a railing in northern England, from playground equipment in Moscow, Russia, and from a pipe supporting a piece of art in Hamburg, Germany. 

Reflections on a World of Ice Formations

Fifteen years ago I knew about icicles and patches of ice on streets and walkways, and that was about it.  Now when it is above freezing part of the day and below freezing part of the day, I look for ice in many places, and often find it.  I have learned much by observing these many forms of ice.  I hope you will join me in the search for ice in its many forms. 

What we do know is that this ice is not a form of frost.  Frost comes about when the air becomes saturated and water vapor is deposited on a surface as an ice crystal.  If the air temperatures are above freezing, we get dew, but when it is below freezing moisture is deposited out of the air as frost.  Figure 2 above shows that frost has been deposited on leaves and blades of grass.  Certainly, in most cases the conditions that are appropriate to the growth of ice are also appropriate to the formation of frost.  For this reason, some of the older names for the formations of ice on plants are called frost flowers and the plants are called such names as frost weed. 

More recently I have come to realize the commonality of ice segregation as the process producing ice on plant stems, pieces of dead wood, pebbles and soil. 

Indeed, there is beauty in the many ways frost forms on surfaces and objects.  There are many sites on the web where photographers show their frost pictures. 

Thank goodness for the Internet and digital cameras for they let us exchange information about these attractive ice formations.  Please look for interesting ice when the freeze/thaw processes are underway.   If you want to know more see my web pages at

Feel free to contact me at  [email protected]   to share your photos of ice of this nature from your early morning outings.

One of the many web pages of Dr. Jim Carter