1. 
   Half-Hardy
   Just as the word depicts, not completely hardy. Good examples re pansies, snapdragons, sweet alyssum. They will tolerate some light frost and cold nights.
   Found op http://www.emilycompost.com/garden_glossary.htm
   
   
2. 
   Half-hardy
   Applied to annuals, this indicates that a plant is able to cope with temperatures down to 0°C (32°F) but not hard frost.
   Found op http://www.bbc.co.uk/gardening/htbg/glossary/half-hardy.shtml
   
   
3. 
   half-hardy
   [adj] - (of plants) requiring protection from frost
   Found op http://www.webdictionary.co.uk/definition.php?query=half-hardy
   
   
4. 
   Half-hardy
   Term used for plants that can generally only be grown outdoors during the summer but which may survive mild winters outdoor in a sheltered position
   Found op http://www.encyclo.co.uk/visitor-contributions.php
   
   
5. 
   half-hardy
   adjective (of plants) requiring protection from frost; `half-hardy annuals`
   Found op http://wordnetweb.princeton.edu/perl/webwn?s=half-hardy
   
   
6. 
   Half-hardy
   Plants unable to survive the winter without protection. Examples include runner beans and sweetcorn.
   Found op http://www.gardeningdata.co.uk/glossary.php
   
   

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