Winter Kill and Rhododendrons - "Dr. Z's" Tip of the Week

Damage from this past winter is beginning to show up now on broad leaf evergreens in the form of winter kill.  This especially true with rhododendrons.
Winter kill really only starts to exhibit it's effects as spring begins to gear up.  The term "winter kill" is an all encompassing title for damage that occurs during the winter due to cold temperatures, drying winds, lack of moisture, and harsh sun.
Winter damage on rhododendrons manifests itself in a couple of ways.  Usually the buds are dried out and the leaves are rolled up along the midrib. The leaves start out as an off green color and progress to brown.  Sometimes the leaves are open, but show browning along the edges and at the tip.  These leaves sometimes develop a secondary disease infection which seldom requires treatment.  In general the exposed foliage over most of the plant is effected by the winter kill symptoms.
It's best to wait before cutting out any seemingly dead branches as they might not be completely dead.  Feed the rhododendrons with an acid based fertilizer such as Hollytone.  If the weather goes to the dry side, be sure to keep them well watered.  The goal is to keep them from undergoing any stress as they have been stressed out enough from the winter damage.
Another garden chore for this week would be to remove any developing seed heads from fading daffodils and tulips.  Once the blooms start to dry up, an enlarged seed head will form at the end of the stem.  Remove this as the bulb will put energy into creating this seed head, and that will use up food from the bulb that will be needed for next year's bloom.  The more of that food reserve that is expended, the smaller the bloom will be next year.

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