Is there some real reason you can't simply use a filter?

Add header row to your table, e.g. Plant, MinTemp;
Activate any single cell in table, and select from menu an Filter option (in my version of Excel it is Home.SortAndFilter.Filter) - you get selection options at column headers;
For 'Min temp' column, click on filter option, select 'Number Filters', then 'Greater than', and type 5 into condition field. Click OK, and you get what you wanted! You didn't like the result - change the filter condition in any way you like.