JARS v55n1 - Tips for Beginners: First Aid to Frozen Rhododendrons

Tips for Beginners: First Aid to Frozen Rhododendrons
Gwen Bell
Seattle, Washington

Reprinted from the Seattle Chapter Newsletter
Based on talk by Lee Fryer, Director of Soils and Research Division of the Lilly Co., and Richard W. Simmons, Director of the Farm and Garden Research Foundation.

Fryer: Nature works the year around. Soil bacteria work the year around and even in the winter the soil bacteria are releasing plant food in a form the plant can use. However, during the winter this is not usually enough for the plant and it must rely upon food stored within the plant itself.

Simmons: When cold weather hits a plant, if the weather is cold enough that the plant freezes, then the pure water in the plant cells separates from the protein and forms ice crystals. If there is more water in the cells than protein, the ice crystal becomes larger and the cell walls may become broken. As fall and winter approach the sugar and salt content of these cells should increase to the point where the amount of available free water left would cause no damage. Then freezing weather would only cause minor ice crystals to form at all. Dehydration is another damaging effect caused by cold weather. If the air is too dry and the plant is unable to bring up water to transpire with, it will soon burn or dry up. This is first noticed on the leaves of the plant.

Mr. Fryer suggested treatment for defoliated plants that were still alive and whose buds were swelling and showing signs of growth. Again referring to nature's way, he cautioned us to be slow and gentle. "Do not worry about plant food at this stage because the plant has enough stored within itself. Do not prune too soon. When the new leaves start to show, spray them and the stem with a mild solution of fish fertilizer, which has thirteen plant food elements that are needed most at this time. Next, examine the root ball area making sure the soil is not soggy and the root ball is not too deep. This must be corrected even if it means lifting the plant gently into a more desirable growing condition and loosening up the root ball."