Question
hi could you please tell me why my yucca plant leaves are very light green and curl in slightly at the sides it looks rather limp new leaves keep growing on it all the time which is quite encouraging but it does not look like the garden centre yuccas which is a lovely rich green colour.

Answer
Hi Julie,
  You probably have some type of insect infestation on the plant. Check the leaves, especially the undersides, carefully to see if you can find any sign of insect presence. Here is a link to an informational guide on insect control on houseplants that I wrote. The guide will give you information on the most common houseplant insects and the different methods to control insect problems;

http://reviews.ebay.com/Insect-Control-On-Houseplants_W0QQugidZ10000000004625662

If there are no insects on the plant then the problem is cultural. Over-watering or problems with water quality is usually the most likely cause. Allow the top 1-2 inches of soil to dry between watering then water the plant with distilled water until a small amount of water drains from the drainage holes in the bottom of the pot. Yucca plants need medium to bright light with little direct sunlight. Too much direct sunlight can cause the leaves to become limp and over-fertilizing can cause the leaves to curl in. The problem with this plant may be caused by several things instead of just one so you will need to carefully consider if you are providing proper care for the plant.
Here is another link to information on general plant care;

http://reviews.ebay.com/Insect-Control-On-Houseplants_W0QQugidZ10000000004625662

The links to these guides can provide you with much more information than I could give you here. There is also a guide on Dracaena care too.
If you have any questions or need additional information please don't hesitate to contact me.
Thanks
  Tracy