​How is a dibber, a thermometer, or a glass bulb used in gardening? 

• A dibber is a tool with a handle on one end and a point on the other, used in the garden to poke holes in preparation for planting seeds, bulbs.  Also known as a dibble or dib.
  
  
• A soil thermometer is useful for planting in that many seeds are particular about soil temperatures.  Check out this Optimal Seed Germination chart to determine planting times. 
  
  
• The glass bulb is filled with water to deliver consistent moisture to a potted plant.  In some tests conducted locally, it is not reliable in that all the water can be released at once resulting in overwatering.  A wicking system may deliver better results.