You don't need to use a special detergent. However if your not using fabric softener you may want to add a couple of tennis balls or dryer balls to the drying cycle. It usually takes a few washes for the sheets to soften up since they don't use a chemical softener like conventional cotton sheets do.

The duvet closes with buttons.

In the main photo the lightest color is Natural, the darker one is Amber and the Green color is Leaf. We do have swatches available if you email you color request to productspecialist@Gaiam.com.

In the additional views with the stacked sheets. The Colors are as follows. Eggplant, Paprika, Terra Cotta, Rattan, Flaxen, Chamois, Petal, Natural, Pearl Grey, Thyme, Sable, Twilight, Indigo and Leaf.

Re: 300 thread count sale sheets. I ordered Natural, which looks like Ivory. Not sure if there are any left. Other than white (which weren't available when I ordered), Natural was the next lightest color.

I believe the color shown is "natural." It's a creamy linen-like color. Scroll down on the picture to see the notations about which colors are shown.